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Dana Nuccitelli is an environmental scientist at a private environmental consulting firm in the Sacramento, California area. He has a Bachelor's Degree in astrophysics from the University of California at Berkeley, and a Master's Degree in physics from the University of California at Davis.

Dana has been researching climate science, economics, and solutions since 2006, and has contributed to Skeptical Science since September, 2010.  He has also blogged at The Guardian, is the author of Climatology versus Pseudoscience, and now writes for Yale Climate Connections.  Dana has published climate-related papers on various subjects, from the build-up of heat in the Earth's climate system to the expert consensus on human-caused global warming.

Follow him on Twitter.


Nuccitelli, D., Way, R., Painting, R., Church, J., & Cook, J. (2012). Comment on ocean heat content and Earth's radiation imbalance. II. Relation to climate shifts. Physics Letters A.

Cook, J., Nuccitelli, D., Green, S.A., Richardson, M., Winkler, B., Painting, R., Way, R., Jacobs, P., & Skuce, A. (2013). Quantifying the consensus on anthropogenic global warming in the scientific literature. Environmental Research Letters, 8(2), 024024+. 

Cook, J., Oreskes, N., Doran, P. T., Anderegg, W. R., Verheggen, B., Maibach, E. W., Carlton, J. S., Lewandowsky, S., Skuce, A. G., Green, S. A., & Nuccitelli, D. (2016). Consensus on consensus: a synthesis of consensus estimates on human-caused global warming. Environmental Research Letters, 11(4), 048002.

Cook, J., Nuccitelli, D., Skuce, A., Way, R., Jacobs, P., Painting, R., Honeycutt, R., Green, S.A. (2014). Reply to Comment on ‘Quantifying the consensus on anthropogenic global warming in the scientific literature: a Reanalysis’. Energy Policy. DOI: 10.1016/j.enpol.2014.06.002

Nuccitelli, D. A., Abraham, J. P., Benestad, R. E., & Mandia, S. A. (2013). Comment on: Akasofu, S.-I. On the Present Halting of Global Warming. Climate 2013, 1, 4–11. Climate, 1(2), 76-83.

Abraham, J., Cook, J., Fasullo, J., Jacobs, P., Mandia, S., & Nuccitelli, D. (2014). Review of the consensus and asymmetric quality of research on human-induced climate changeCosmopolis2014(1), 3-18.

Benestad, R. E., Hygen, H. O., Dorland, R. V., Cook, J., & Nuccitelli, D. (2013). Agnotology: learning from mistakes. Earth System Dynamics Discussions, 4(1), 451-505.

Nuccitelli, D., Richter, M. J., & McCall, B. J. (2005). A search for interstellar carbon-60. In IAU Symposium (Vol. 235, p. 236P).

Encrenaz, T., Bézard, B., Greathouse, T., Holmes, S., Richter, M., Nuccitelli, D., & Forget, F. et al. (2006, February). Ground-based high-resolution IR spectroscopy of Mars: H2O and H2O2 mapping, search for CH4, and determination of CO2 isotopic ratios. In Second Workshop on Mars Atmosphere Modelling and Observations, held February.


Recent blog posts

Climate change is worsening California's hellish wildfires

Posted on 25 August 2020 by dana1981

This is a re-post from Yale Climate Connections

Like a modern-day Ebenezer Scrooge escorted by the Ghost of Summers Yet to Come, California is catching a glimpse of its future summer weather. The view is a hellish one.

Within a two-week span in August, California saw:

  • the “fire tornado” just north of Lake Tahoe
  • 130 degrees Fahrenheit heat in Death Valley, which may be the hottest temperature ever reliably recorded on Earth
  • a largely dry thunderstorm with 11,000 lightning strikes across California over 72 hours, igniting more than 300 wildfires, including two of the three largest ever recorded in the state (and still growing), creating the worst air quality in the world
  • one million acres burned in California in 2020 with 4 months to go in fire season
  • tens of thousands of people evacuated from their homes as the fires drew near
  • rolling power blackouts during a record heat wave
  • gray, unhealthy air. A blood red sun. Flakes falling from the sky, coating everything below in a layer of white… not snow, but ash.

These ghastly scenes all bear links to climate change, and as a result, climate scientists expect them to occur more frequently in the future as global warming continues to raise temperatures and dry the landscape. As California Gov. Gavin Newsom put it in a recording for the Democratic National Convention, “Climate change is real. If you are in denial about climate change, come to California.”

Better yet, don’t. At least not right now.

The heat dome punishing the American Southwest

California’s severe August weather is linked to a ridge of high pressure, also referred to as a “heat dome,” stuck over the American Southwest. The heat dome pulled moisture from a tropical storm in the Pacific, fueling rare summer storms that triggered the thousands of lightning strikes that have ignited wildfires across the state. The hot air inside the dome contributed to the record heat, which evaporated most of the storm’s precipitation before it could reach the ground. The hot and dry conditions on the ground created more fuel for the fires to spread farther and faster.

According to meteorologist Ryan Maue, as reported in the Washington Post, almost all of the high-powered heat domes over the past six decades have occurred since 1983, and the overwhelming majority of those since 1990. Climate scientists will need to investigate the role that climate change played in the evolution of this particular heat dome. However, a growing body of research suggests that human-caused global warming increases the frequency with which such high-pressure ridges get stuck in one place for long periods of time as a result of wavy patterns forming in a slowed jet stream.

To Penn State climate scientist Michael Mann, lead author of a 2018 study on this subject, the heat dome in the American Southwest looks familiar.

“The extreme heat out West right now is associated with a very strong, stable ridge that resembles, in both its persistence and intensity, the ridge that gave us unprecedented heat, drought and wildfire out west in mid-summer 2018,” Mann said in an email exchange. “Knowing that, I would venture a guess that the same atmospheric phenomenon (planetary wave resonance) that was responsible for that setup and the unusually persistent weather extremes in Europe and elsewhere at that time might be playing a role here too. But that assessment will need to be performed by actually doing the diagnostics.”



The Trump EPA is vastly underestimating the cost of carbon dioxide pollution to society, new research finds

Posted on 30 July 2020 by dana1981

This is a re-post from Yale Climate Connections

Government rulemakers looking to decide how much money to spend to avoid adding more greenhouse gases to the atmosphere need a good estimate of what a warming climate will cost in social damages, for example through more extreme weather events.

That point makes the “social cost of carbon” one of the most critically important metrics underlying regulation of climate pollutants. An estimate of the dollar costs of each ton of carbon pollution caused by climate change, the social cost of carbon guides federal agencies that are required to consider the costs and benefits of proposed regulations. Federal agencies so far have used the social cost of carbon while writing regulations with more than $1 trillion in economic benefits.

In 2010, a governmental interagency working group in the Obama administration established the first federal social cost of carbon estimate of $45 per ton of carbon dioxide pollution. In 2017, newly inaugurated President Donald Trump quickly disbanded the interagency group by executive order, and within months his EPA slashed the metric to between $1 and $6. The latest research by an independent team of scientists concludes that the social cost of carbon should actually start at about $100 to $200 per ton of carbon dioxide pollution in 2020, increasing to nearly $600 by 2100.

Should presumptive Democratic nominee Joe Biden win the presidency in the November election, his federal agency appointees will undoubtedly set about revising the social cost of carbon to reflect the up-to-date climate science and economics research. The revised social cost of carbon will in turn justify more stringent federal climate regulations. A Donald Trump second term would instead result in another four years of underestimated climate impact costs and continued delays in efforts to curb carbon pollution.

A history of attacks

Since its inception, the social cost of carbon has been a target of those opposing climate regulations, including many Republican office holders in Washington, D.C. The neutered social cost of carbon estimate has now been used to justify weakening three major climate regulations: undoing the Clean Power Plan, freezing vehicle fuel efficiency standards, and, in July 2020, setting airplane greenhouse gas standards to levels matching those the industry already has already met.

In December 2017, congressional Democrats asked the Government Accountability Office to examine the Trump EPA’s new method for calculating the social cost of carbon. The GAO published its report in June 2020.



House Democrats eye 2021 with comprehensive climate action plan

Posted on 2 July 2020 by dana1981

This is a re-post from Yale Climate Connections

House Democrats have released a comprehensive report showing how – if they control the White House and both the Senate and the House of Representatives – they might move forward on climate change. Their “Climate Crisis Action Plan,” released June 30 by the new House Select Committee on the Climate Crisis, runs more than 500 pages and would move the U.S. toward net-zero greenhouse gas emissions over the next three decades.

The committee, established in 2018 when Democrats regained majority control of the House, designed the report with an eye the earlier “Green New Deal” initiative and also on current-day environmental and racial justice concerns. Backers of their effort acknowledge slim chances of enactment of major climate legislation in the current Congress, where Republicans hold a majority in the Senate and where scheduling of floor action is controlled by Kentucky Republican Majority Leader Mitch McConnell.

The committee pointed to 17 official hearings and countless staff meetings with various stakeholders as a basis for the new Democratic climate plan. The detailed report spells out specific steps for tackling emissions from across a broad cross-section of the U.S. economy. Running throughout the report are themes considering investment in infrastructure and clean energy; worker assistance and efforts to provide a “fairer economy”; environmental justice and efforts to meet the needs of underserved communities; community resilience; public health and new approaches to agriculture; and national security.

Let’s examine some of the specific sectors and policies addressed in the plan.



What 'Planet of the Humans' gets wrong about renewable energy

Posted on 25 June 2020 by dana1981

This is a re-post from Yale Climate Connections

Like an earthquake rumbling down the San Andreas Fault, Jeff Gibbs’ and Michael Moore’s controversial film “Planet of the Humans” tore a rift through the environmental movement, a rift its leaders would not yearn for in an election year. After activists have spent decades painstakingly building popular support for climate policies focused on developing and deploying low-carbon technologies, the film and its defenders dismiss these as false solutions, saying the focus should instead be on curbing population, consumption, and economic growth.

Both those factions agree that, as the IPCC has concluded, human civilization must cut its carbon emissions to zero within a few decades to avert a climate crisis. Is there a scientific way to determine which group is right about the best way to achieve that goal? As a matter of fact, there is.

Kaya formula

In 1990, Japanese energy economist Yoichi Kaya developed a simple and elegant formula called the Kaya Identity that can help answer the question: F is human carbon emissions, P is human population, G is economic activity as measured by gross domestic product (GDP), and E is energy consumption.

Only one plausible solution: zero emissions

For carbon emissions (F) to reach zero, just one of the four terms on the right side of the formula must be zero. So either human population (P), per-person economic activity (G/P), the energy consumed to power the economy (E/G), or the carbon footprint of energy (F/E) must be zero. Common sense gives us the answer to the debate: clean energy is the only plausible route to zero emissions.

And we’re in luck. Clean energy would not destroy humanity or human civilization, which would be the result of zeroing the population, economy, or energy use. Contrary to the false claims in “Planet of the Humans,” carbon emissions from energy can plausibly reach zero. In fact, a new report from the University of California, Berkeley concludes that U.S. electricity could be supplied by near-zero emissions sources (like wind, solar, hydro, nuclear, and geothermal, plus storage) in short order. About 40% of American electricity is supplied by clean sources as of 2020, and the report concludes that this number could feasibly be scaled up to 55% by 2025, 75% by 2030, 90% by 2035, and 100% by 2045.

If an energy-devouring economy like that of the United States can do it, one might argue, the rest of the world can too.

The Berkeley report also concludes that replacing fossil fuels with clean energy sources would prevent 85,000 premature deaths caused by air pollution and create half a million permanent jobs (mostly associated with manufacturing and construction of clean energy infrastructure), while electricity rates would only be 12% higher than business-as-usual (and cheaper than today’s rates).



Most Trump environmental rollbacks will take years to be reversed

Posted on 4 June 2020 by dana1981

This is a re-post from Yale Climate Connections

The Trump administration, after less than one full first term, has every likelihood of being adjudged the most anti-climate, anti-science, and anti-environment executive branch in U.S. history. With numerous high-level Trump nominees having cut their teeth as lobbyists with major polluting industries, the administration has been steadfast in weakening or eliminating major conservation and environmental regulations and programs.

Notwithstanding President Trump’s claims to want “crystal clean water and the cleanest and the purest air on the planet,” his administration has determinedly gone about reversing at least 100 environmental rules. While initial Trump EPA cutbacks under Administrator Scott Pruitt were hampered by his self-inflicted scandals, the agency under Administrator Andrew Wheeler has quietly worked to achieve many of the same ends. Wheeler’s environmentalist critics are fond of saying that he is “so bad because he is so good at being bad,” thereby often avoiding incriminating headlines that had plagued Pruitt.

The extensive regulatory cutbacks raise questions about how much long-term damage they might pose to air and water quality and to serious efforts to address climate change. With a presidential election now five months away, they also raise “What if…” questions about whether such cutbacks might be sustained or how quickly they might be reversed by a new administration.

Let’s consider just five of the most significant regulatory actions affecting the climate and air quality.



Did Michael Moore's Film Bash Renewable Energy?

Posted on 25 May 2020 by dana1981

The film Planet of the Humans with Micheal Moore’s name on it says that wind power and renewables are no better than fossil fuels. How honest is the film?



Michael Moore's 'Planet of the Humans' documentary peddles dangerous climate denial

Posted on 1 May 2020 by dana1981

This is a re-post from Yale Climate Connections

Environmentalists and renewable energy advocates have long been allies in the fight to keep unchecked industrial growth from irreversibly ruining Earth’s climate and threatening the future of human civilization. In their new YouTube documentary “Planet of the Humans,” director Jeff Gibbs and producer Michael Moore argue for splitting the two sides. Their misleading, outdated, and scientifically sophomoric dismissal of renewable energy is perhaps the most dangerous form of climate denial, eroding support for renewable energy as a critical climate solution.

“Planet of the Humans” by the end of April had more than 4.7 million views and fairly high scores at the movie critic review aggregator Rotten Tomatoes. The documentary has received glowing reviews from numerous climate “deniers” whose names are familiar to those in the climate community, including Steve Milloy, Marc Morano, and James Delingpole. Some environmentalists who have seen the movie are beginning to oppose wind and solar projects that are absolutely necessary to slow climate change.

The film by these two “progressive” filmmakers may succeed where Fox News and right-wing talk radio have failed: to undermine humanity’s last best hope for positive change. As energy journalist Ketan Joshi wrote, the film is “selling far-right, climate-denier myths from nearly a decade ago to left-wing environmentalists in the 2020s.”

The film follows Gibbs as he visits various green technology sites in the United States and ostensibly learns that each one is just as bad as the fossil fuel infrastructure that it would replace. Unfortunately, the movie is littered with misleading, skewed, and outdated scenes.

“Planet of the Humans”‘ approach is fundamentally flawed – Gibbs focuses almost exclusively on the imperfections of technologies like solar panels, wind turbines, biomass, and electric cars without considering their ability to reduce carbon and other pollutants. The film suggests that because no source of energy is perfect, all are bad, thus implying that the very existence of human civilization is the problem while offering little in the way of alternative solutions.



A leading scientist's transition from climate science to solutions

Posted on 30 April 2020 by dana1981

This is a re-post from Yale Climate Connections

Kim CobbGeorgia Tech scientist Kim Cobb emphasizes a point at a December 2019 TedX talk.

Dr. Kim Cobb is an award-winning climate scientist at Georgia Tech and a lead author of the next Intergovernmental Panel on Climate Change report. However, over the past several years, the very climate changes she has researched have conspired to change the course of her career.

2016 was the turning point. That year, global warming combined with a monster El Niño event to shatter the previous record for Earth’s hottest year and devastate the coral reefs she had studied for nearly two decades. In 2017 and 2018, flooding events along the Georgia coast brought the impacts of climate change even closer to home.

“I decided to go ‘all in’ on climate solutions, personally and professionally,” Dr. Cobb said in a phone interview from her home office. She began changing her lifestyle to lower her personal carbon footprint, slashing her flights to scientific conferences despite that decision’s professional costs, and shifting her focus in the direction of climate solutions.



Coronavirus doubters follow climate denial playbook

Posted on 14 April 2020 by dana1981

This is a re-post from Yale Climate Connections

For the climate community, observing U.S. national political leaders’ responses to the coronavirus pandemic has been like watching the climate crisis unfold on fast-forward. Many – particularly on the political right – have progressed through the same five stages of science denial in the face of both threats.


For climate change, the denial process began decades ago. NASA climate scientist James Hansen testified to Congress in 1988 about the dangers posed by global warming; the fossil fuel industry formed the Global Climate Coalition the very next year to launch a campaign casting doubt on mainstream climate science. In November 1989, President George H.W. Bush’s chief of staff, climate denier John Sununu, sabotaged efforts to develop the first international climate change treaty. Exxon in particular spent the following decades and tens of millions of dollars funding a network of think tanks to propagate climate science denial. In a memo leaked in 2003, Republican strategist Frank Luntz advised G.O.P. politicians, “You need to continue to make the lack of scientific certainty a primary issue in the debate.”



Aggressive action to address climate change could save the world $145 trillion

Posted on 26 March 2020 by dana1981

This is a re-post from Yale Climate Connections

A respected research group, Project Drawdown, finds that deploying solutions consistent with meeting the Paris climate targets would cost tens of trillions of dollars globally. But crucially, those outlays would also yield long-term savings many times larger than the up-front costs.

The new 2020 Drawdown Review includes economic estimates of the capital costs to deploy each solution, net lifetime operation costs, and lifetime profits from the sale of products produced by the agricultural solutions. The key conclusion is that while the upfront costs are substantial – around $25 trillion globally – the resulting savings and profits are five to six times larger.

Project Drawdown is a nonprofit organization that evaluates climate solutions nations could deploy to reach the point where greenhouse gas levels in the atmosphere begin to decline (the threshold of carbon “drawdown”). Achieving drawdown will require phasing out the use of fossil fuels that add carbon and strengthening the natural sinks that absorb carbon. In 2017, the group published the New York Times bestselling book Drawdown, which described the 100 most substantive solutions to global warming based on a comprehensive scientific review by the project’s research team.

The new Drawdown Review considers two potential pathways. Scenario 1 envisions how climate solutions could be deployed to meet the Paris target of staying below 2 degrees Celsius (3.6 degrees Fahrenheit) hotter than pre-industrial temperatures, in which the point of carbon drawdown is reached in the mid-2060s. Scenario 2 is more ambitious, keeping global temperatures below the aspirational Paris target of 1.5 degrees C (2.7 degrees F) by achieving carbon drawdown in the mid-2040s. In the more aggressive Scenario 2, global economic savings are $145 trillion, with an additional $29 trillion in profits generated from the agricultural sector – the latter on its own offsetting the initial $28 trillion capital costs. Both the Scenario 1 and 2 savings estimates are calculated over the life times of the solutions.



How much would planting 1 trillion trees slow global warming?

Posted on 24 February 2020 by dana1981

This post has been incorporated into the new rebuttal to the myth 'Planting a trillion trees will solve global warming' with the short URL

During his 2019 State of the Union address, Donald Trump announced that the United States will join the Trillion Trees Initiative. House Republicans plan to introduce legislation to plant 3.3 billion trees per year domestically over the next 30 years (an 800 million increase over the 2.5 billion per year that are already planted in the U.S.), as well as encouraging carbon capture and sequestration from power plants by providing research & development funding and creating a tax incentive for using the technology. This poses the question – how much impact would these carbon sequestration proposals (especially the tree planting initiative) have on atmospheric carbon dioxide (CO2) levels and global warming?

Bastin et al. (2019) sought to quantify the potential global tree restoration potential and the carbon sequestration associated with that reforestation and afforestation. The study concluded, “there is room for an extra 0.9 billion hectares of canopy cover, which could store 205 gigatonnes of carbon [GtC] in areas that would naturally support woodlands and forests.” For comparison, humans have emitted approximately 640 GtC, so this would represent a significant chunk of human emissions to date. 900 million hectares of land is approximately the size of the United States.

However, several comments identified flaws in the Bastin et al. estimate. Friedlingstein et al. (2019) noted that their estimate of the potential carbon storage of trees in each biome did not account for the carbon already stored in those regions, and thus concluded:

the potential carbon storage would be substantially lower than reported … Moreover, forests affect climate through biophysical feedbacks, such as changes in albedo or evapotranspiration, which can counteract the cooling effect from CO2 uptake … These biophysical feedbacks were not discussed in the article and could substantially reduce the potential of forest reforestation in some of the considered regions.

Veldman et al. (2019) in concluding that the true maximum tree carbon sequestration potential is closer to 42 GtC, noted:



On climate misinformation and accountability

Posted on 10 February 2020 by dana1981

Lately there has been a great deal of misinformation regarding the origins and purpose of Skeptical Science.  As John Cook wrote nearly a decade ago, Skeptical Science is primarily a website that debunks climate misinformation with peer-reviewed science.  Despite the ever-worsening impacts from climate change, with record after record being broken in our warming climate, misinformation casting doubt on climate science is rampant and showing no signs of going away. Sadly, a resource that shines disinfecting daylight on climate misinformation is needed more than ever.

When we find ourselves frequently debunking myths from the same sources, we collect that information in our 'Misinformation by Source' database. There are several reasons why we created that particular database. 

First, because we at Skeptical Science simply love data.  That's the backbone of our website.  We love to gather it, analyze it, and organize it for easy reference. One of the strengths of our site is making our debunkings accessible in different ways for ease-of-use, such as our multi-level rebuttals, translations, short URLs for easy sharing, and organized in a fact-myth-fallacy format.

Second, for the sake of accountability.  If an individual propagates a climate myth to the public via a setting like a blog or media interview or congressional testimony, it's useful to have a resource documenting if that individual has frequently promoted climate myths in the past.  If so, that individual should be considered a relatively unreliable source of accurate climate science information. 

To those who object to being included on the 'Misinformation by Source' database, the remedy is simple – stop purveying climate myths.  Perhaps acknowledge the mistakes you made in communicating those myths.  Take responsibility for your own actions.



Earth is heating at a rate equivalent to five atomic bombs per second

Posted on 6 February 2020 by dana1981

This is a re-post from the Bulletin of the Atomic Scientists

The heat absorbed in Earth’s oceans reached a new record in 2019, found a recent study published in the journal Advances in Atmospheric Sciences. Despite the fact that this has been the case for almost every year over the past decade, this information dominated the news cycle, with some particularly viral headlines noting that the amount of energy accumulating in the oceans is equivalent to detonating five Hiroshima atomic bombs per second, every second over the past 25 years.

While stunning, this isn’t a new analogy. After we published a paper about Earth’s energy accumulation in 2012, my colleagues and I at Skeptical Science created a website called that provided a widget that websites can include on their homepages to illustrate the amount of heat accumulating on Earth as compared to the energy in the Hiroshima atomic bomb. The widget also uses other analogies to get the idea across, such as how the amount of heat accumulated compares to the energy in Hurricane Sandy, or 6.0 magnitude earthquakes, or Big Bens full of dynamite, or millions of lightning bolts. Improved ocean heat measurements have since revised the rate of warming upwards from four to five ‘Hiros’ per second. (For the record, as of the writing of this article, our climate has accumulated the equivalent of a total of more than 2.8 billion Hiroshima bombs’ worth of heat since 1998.)

Our team wasn’t the first to use this analogy. In 2010, oceanographer John Lyman compared the rate of ocean warming to atomic bombs, and James Hansen used the Hiroshima atomic bomb analogy in his February 2012 TED talk. One might say that the comparison has come under heat, however. Some criticize the analogy for exploiting or being insensitive to the horrors suffered by the people of Hiroshima. Others have complained that the analogy is imperfect, as all analogies are, by definition.

On the other hand, the use of Hiros has one major upside. Earth and especially its oceans have been accumulating such a vast amount of heat due to human-caused global warming that it’s difficult to comprehend. Most people have little if any sense what 10 zettajoules per year—the amount of heat energy absorbed per year by the Earth—means. That’s why climate communicators have searched for a metric of comparison that the public can grasp. It’s relatively easy to visualize five atomic bombs detonating every second, and consequently comprehend the vast amount of energy being absorbed by the Earth’s climate system.

For those who nevertheless object to the Hiros analogy, perhaps microwaves offer a more palatable comparison. The heat accumulating in Earth’s oceans over the past 25 years is also equivalent to every person now on Earth running 35 standard household microwave ovens nonstop during Justin Bieber’s entire lifetime.



With the En-ROADS climate simulator, you can build your own solutions to global warming

Posted on 27 January 2020 by dana1981

This is a re-post from Yale Climate Connections

Killer hurricanes, devastating wildfires, melting glaciers, and sunny-day flooding in more and more coastal areas around the world have birthed a fatalistic view cleverly dubbed by Mary Annaïse Heglar of the Natural Resources Defense Council as “de-nihilism“. One manifestation: An increasing number of people appear to have grown doubtful about the possibility of staving-off climate disaster. However, a new interactive tool from a climate think tank and MIT shows that humanity could still meet the goals of the Paris accord and limit global warming.

By itself, a carbon tax rising to around $200 per ton of emissions would bring the world about halfway to the Paris goal, according to the En-ROADS interactive tool developed by the MIT Sloan School of Management and the Climate Interactive think tank. Countries would also need to implement other aggressive climate policies targeting the many different sectors of the economy that generate large-scale greenhouse gas emissions. The tool allows a user to figure out how:

– civilization must change the fuel mix supplying the world’s energy and boost efficiency;
– the extent to which more buildings and vehicles must be electrified;
– strategies could help reduce deforestation and how to plant more trees of the optimum species at the right locations; and
– carbon capture technology could be relied upon to remove greenhouse gases from the atmosphere.

Carbon taxes seen as the most effective tool

According to Climate Interactive’s climate and energy lead, Ellie Johnston, “Behind En-ROADS is a system dynamics model that weaves the interdependencies and feedbacks of our global climate system with the actions that we need to take globally to address climate change.”



How climate change influenced Australia's unprecedented fires

Posted on 18 January 2020 by dana1981

This is a re-post from Yale Climate Connections, and has been adapted into a new myth rebuttal on climate-wildfire connections with the short URL

Australia’s frightening bushfires, which kicked off an early fire season in September 2019, have already had cataclysmic effects, and the continent is still just in the early months of the southern hemisphere’s summer. The New South Wales Rural Fire Service has described the bushfires as unprecedented in size and scale, having burned more than 46 million acres (18.6 million hectares), killed at least 29 people, and destroyed more than 2,200 homes.*

Parts of Australia have had the worst air quality in the world. The air quality in Sydney has literally been alarming, having set off smoke alarms in buildings throughout the city’s central business district and exceeded hazardous levels for more than 30 days. Military assets have been deployed in response to the fires at a scale not seen since World War II. Researchers estimate that more than a billion animals have been killed. Several species will likely be pushed to extinction.

The conditions and climate change-wildfire connections in Australia have been strikingly similar to those amplifying California’s record 2018 wildfire season, but on a much larger scale. Scientific unknowns remain regarding some of those connections, but others are a straightforward result of physics – more heat creates more wildfire fuel.

The politics and climate policy environment down under, on the other hand, more closely bring to mind those at the national level in the U.S. than to the situation in California.



2019 in climate science: A continued warming trend and 'bleak' research

Posted on 7 January 2020 by dana1981

This is a re-post from Yale Climate Connections

The last six years have been the six hottest globally ever recorded by humans.

2014 had been the hottest year up to that point, until the record was shattered in 2015, and again in 2016 thanks to a monster El Niño event. El Niños bring hot water up to the ocean surface where it warms the temperature of the surface air that most directly influences and interests humanity. Next came 2017, the second-hottest year recorded by humans, but far and away the hottest that wasn’t influenced by an El Niño event. And then 2018, the fourth-hottest overall, but by far the hottest year on record that was cooled by a La Niña event.

And now 2019, warmed by a moderate El Niño event and as such not as hot as 2016 with its monster El Niño; but it was nevertheless the second-hottest year on record, and quite possibly the second-hottest in the history of human civilization.

As global warming has continued, so too has the volume of peer-reviewed reports and studies published by climate scientists documenting its accelerating impacts. Here are some of the most influential climate change research papers published in calendar 2019.



Climate models have accurately predicted global heating, study finds

Posted on 5 December 2019 by dana1981

This is a re-post from The Guardian and has been incorporated into the rebuttals to the myth 'Models are unreliable'

Climate models have accurately predicted global heating for the past 50 years, a study has found.

The findings confirm that since as early as 1970, climate scientists have had a solid fundamental understanding of the Earth’s climate system and the ability to project how it will respond to continued increases in the greenhouse effect. Since climate models have accurately anticipated global temperature changes so far, we can expect projections of future warming to be reliable as well.

The research examines the accuracy of 17 models published over the past five decades, beginning with a 1970 study and including 1981 and 1988 models led by James Hansen, the former Nasa climatologist who testified to the US Senate in 1988 about the impacts of anthropogenic global heating. The study also includes the first four reports by the UN’s intergovernmental panel on climate change (IPCC).

“We found that climate models – even those published back in the 1970s – did remarkably well, with 14 out of the 17 model projections indistinguishable from what actually occurred,” said Zeke Hausfather, of the University of California, Berkeley, and lead author of the paper.

Based on modern climate model projections, if countries follow through with current and pledged climate policies, the world is on track for about 3C of warming above pre-industrial temperatures by 2100 – a situation the IPCC and others predict would be catastrophic.

The challenge in evaluating climate model accuracy lies in the fact that due to computing power limitations, simulations are only run for a few specific future greenhouse gas emissions scenarios. There are an infinite number of such possible scenarios, but real-world emissions will follow only one path, and it will never exactly match the few scenarios input into climate models. Thus, if Earth warms less than in a climate model projection, it does not necessarily mean the model was inaccurate.



UN report: Pollution from planned fossil fuel production would overshoot Paris climate goals

Posted on 2 December 2019 by dana1981

This is a re-post from Yale Climate Connections

In the 2015 international Paris Climate Agreement, nearly every country [see editor’s note] agreed to try and limit global warming to no more than 2 degrees Celsius (3.6 degrees Fahrenheit) and preferably closer to 1.5 degrees Celsius (2.7 degrees Fahrenheit) above pre-industrial temperatures. Achieving these goals will require dramatic changes, as the world has already warmed 1 degree Celsius (1.8 degrees Fahrenheit), and temperatures, fossil fuel consumption, and carbon pollution all are continuing to rise.

To determine how far off track emissions are with respect to the Paris goals, groups like the International Energy Agency and Climate Action Tracker evaluate each country’s climate policies. According to their analyses, were each country to follow through only with current policies, global temperatures would rise about 3 degrees Celsius (5.4 degrees Fahrenheit) above pre-industrial temperatures by the year 2100 – a level of warming that would result in severe and dangerous climate changes.

In addition, a new report produced by the United Nations Environment Programme, UNEP, and a coalition of research organizations takes a different approach: The report examines government plans for fossil fuel production and the amount of carbon pollution and global warming that would result if all these fuels were burned.

“Our collective failure to act early and hard on climate change means we now must deliver deep cuts to emissions”, UNEP Executive Director Inger Andersen said in a statement releasing the report. So urgent is the need for action, he said, that “every city, region, business and individual need(s) to act now”.

The resulting picture is indeed bleak – total carbon emissions between now and 2030 from global fossil fuel production plans are about 10% higher than those from the current climate policies that would put the world on track for 3 degrees Celsius warming by 2100. These fossil fuel plans present a difficult impediment to meeting the Paris climate goals.

The challenge, by the numbers

According to the newly released figures, to stay on track to meet the 2 degrees Celsius Paris target, the fossil fuel supply can release only about 350 billion more tons of carbon dioxide between now and 2030, and a total of 550 billion tons by 2040. For the 1.5 degrees Celsius target, the numbers are about 300 billion tons by 2030 and 450 billion tons by 2040.

Based on the analyses of current pledged climate policies, humans are currently on track to exceed the 2 degree path by 17% by 2030 and 36% by 2040. Those are policies that would instead send the world towards the 3 degrees Celsius warming scenario by 2100.

However, based on countries’ fossil fuel production plans, carbon pollution will be about 10% higher yet. Those plans translate to about 450 billion tons of carbon dioxide released between now and 2030, and nearly 850 billion tons by 2040. For the latter date, it’s an overshoot of the 2 degrees Paris carbon budgets by 50%, and 85% too much carbon to stay on the 1.5 degrees Celsius path.

In short, if countries follow through with their current fossil fuel production plans, the world will be on track to warm more than 3 degrees C (5.4 degrees F) by 2100, and meeting the Paris targets would become virtually impossible.



New report finds costs of climate change impacts often underestimated

Posted on 20 November 2019 by dana1981

This is a re-post from Yale Climate Connections

Climate economics researchers have often underestimated – sometimes badly underestimated – the costs of damages resulting from climate change. Those underestimates occur particularly in scenarios where Earth’s temperature warms beyond the Paris climate target of 1.5 to 2 degrees C (2.7 to 3.6 degrees F).

That’s the conclusion of a new report written by a team of climate and Earth scientists and economists from the Earth Institute at Columbia University, the Potsdam Institute for Climate Impact Research, and the Grantham Research Institute on Climate Change and the Environment. It’s a conclusion consistent with the findings of numerous recent climate economics studies.

Once temperatures warm beyond those Paris targets, the risks of triggering unprecedented climate damages grow. However, because the rate and magnitude of climate change has entered uncharted territory in human history, the temperature thresholds and severity of future climate impacts remain highly uncertain, and thus difficult to capture in climate economics models. Put simply, it’s difficult to project the economic impacts resulting from circumstances which are themselves unprecedented.

For example, if the science community does not know the temperature at which various “tipping points” might occur – things like accelerated ice sheet collapse or large carbon releases from the warming oceans or melting permafrost – then economics models will exclude the associated impacts (rapid sea-level rise or accelerated climate change).

Additionally, climate change economic cost estimates have traditionally suffered from questionable assumptions about continued economic growth, and from an inability to account for non-monetized values.



Here Are 3 Climategate Myths That Have Not Aged Well

Posted on 18 November 2019 by dana1981

This is a re-post from DeSmogUK

Excessive media coverage of an email hacking tilted the outcome of a critically important event against the victims of the crime. Sound familiar?

In 2016, it happened to the Hillary Clinton presidential campaign and the Democratic National Committee. That was déjà vu for climate scientists, who seven years earlier had experienced a nearly identical chain of events leading up to the 2009 UN climate change conference in Copenhagen. 

In summary: emails from the University of East Anglia in the UK were hacked, and many journalists assumed that where there was smoke, there must be fire. Even the Daily Show’s Jon Stewart jumped on the bandwagon, accusing climate scientists of trying to “trick you” based on a few selective, out-of-context quotes from the hacked emails (though he also later ripped the media for not covering the debunking of the Climategate myth). Commentators at the time were divided over whether this was a media storm, or just a storm in a very British teacup.

Nonetheless, the Copenhagen climate summit a few weeks later was widely considered a failure. That wasn’t only because of the hacked emails, just as another cache of emails aren’t the sole reason for the words “President Donald Trump” — but in both cases the media-amplified story played a significant role in shaping subsequent events. 

Nine separate inquiries into the email hack exonerated the climate scientists, but came well after the damage had been done. And a decade on, many of the climate science denial myths that emerged from the email hack are still in play.

So, on the 10th anniversary of what came to be known as ‘Climategate’, let’s examine three of the key email quotes that so captured the media’s attention, and how the associated science has since evolved.

Spoiler: the deniers’ lies haven’t aged well.

The misunderstood 'trick'

One quote regularly mangled (most recently in a myth-filled Telegraph article, which was evaluated by the climate scientists at Climate Feedback as having “very low” scientific credibility) referred to using “Mike’s Nature trick … to hide the decline.” The ellipses mask that two separate issues were being discussed in this hacked email. 

First, climate scientist Michael Mann’s “Nature trick” simply refers to adding temperature measurements from modern instruments to a chart illustrating indirect “proxy” temperature estimates (i.e., analyzing tree ring sizes) in the more distant past. The use of the word “trick” in the email was in the context of “trick of the trade,” not “tricking the audience.” If the latter were the case, the use of two different sources of data would not have been labeled as explicitly as possible in Mann’s scientific paper and subsequent reports.

Second, “hiding the decline” referred to the fact that indirect proxy temperature estimates from tree rings were known to be unreliable after about 1960. From about 1960 to 1990 they showed temperatures falling, whereas we know temperatures actually rose during that time. 

Tree ring data matched other temperature records accurately prior to 1960 before diverging from the reliable instrumental record thereafter. Climate science research has linked this so-called “divergence problem” to increases in human-caused pollution in recent decades. The email in question was merely suggesting adding reliable instrumental temperature measurement data so that the chart being discussed didn’t end with a segment of data showing a “decline” that was known to be inaccurate. So, in fact, the “trick” was an effort to give as accurate information as possible (rather than the opposite, as was repeatedly alleged).

A related quote (also included in the Telegraph article) claimed that climate scientist Jonathan Overpeck asserted that “we have to get rid of the Medieval Warm Period (MWP).” This is a fabrication — Overpeck actually said, “I'm not the only one who would like to deal a mortal blow to the misuse of supposed warm period terms and myths in the literature.” 

Overpeck was correct that the MWP is incorrectly referenced regularly. For example, the recent much-maligned Telegraph article went on to claim that the MWP (which roughly spanned the years 900 to 1300 AD) “was even hotter than today,” which is a relatively widespread myth. Numerous studies have reconstructed temperatures over the past several thousand years since Mann and colleagues published their paper in the scientific journal Nature in 1998. All have arrived at the same conclusion: that the MWP was at most a small blip in average global temperatures and that current temperatures are significantly hotter. 

The most recent and robust such reconstruction was completed by a team of over 5,000 scientists from more than 100 countries contributing to the Past Global Changes (PAGES) 2k network, which produced the following chart of global temperatures over the past 2,000 years. It shows temperatures today rapidly rising above the historical record like the blade of a hockey stick.

Pages 2k

Global mean surface temperature history over the Common Era (Pages 2k, Nature Geoscience, 2019)



Brief overview of new IPCC report on oceans and ice risks

Posted on 14 October 2019 by dana1981

This is a re-post from Yale Climate Connections

On the heels of its August special report on climate and land, the Intergovernmental Panel on Climate Change (IPCC) in late September published another special report, this one focused on oceans and ice.

This latest report was authored by 104 climate scientists from 36 countries and reflecting findings in 6,981 studies. It contains a wealth of information – its Summary for Policymakers alone runs 45 pages – but some of the key points can be summarized as follows:

  • Sea-level rise is accelerating because the Greenland and Antarctic ice sheets are melting at an increasing rate;
  • The oceans, while still basic, are becoming more acidic, which will have serious consequences for coral reefs and shell-building marine species;
  • The oceans are warming rapidly, leading to more frequent marine heatwaves, which also damage coral reefs;
  • Researchers are beginning to see more of the most intense hurricanes, those in Category 4 and 5, which in combination with higher sea levels and increased precipitation pose increasing risks and damages to coastlines;
  • Melting of permafrost could become a major feedback, adding carbon emissions and global warming in energy scenarios with significant continued fossil fuel burning;
  • Ocean oxygen levels are declining, which in combination with rising temperatures drives marine species away from the equator toward the poles, and, in concert with algal blooms, could lead to reduced seafood catches at fisheries.

Sea-level rise is accelerating

The claim that sea-level rise is not accelerating has long been a popular myth among those challenging climate science. Measurement data indeed are noisy, making it difficult to detect a change in the rate at which the oceans are rising, but some recent studies have been able to detect an acceleration. The IPCC report confirms this conclusion, noting with high confidence that “Areas of concern in earlier IPCC reports, such as the expected acceleration of sea-level rise, are now observed.”



A brief guide to the impacts of climate change on food production

Posted on 23 September 2019 by dana1981

This is a re-post from Yale Climate Connections by Daisy Simmons with input from from Dana Nuccitelli on the latest IPCC report

Food may be a universal language – but in these record-breaking hot days, so too is climate change. With July clocking in as the hottest month on Earth in recorded history and extreme weather ramping up globally, farmers are facing the brunt of climate change in croplands and pastures around the world.

Here in the U.S., for instance, climate impacts like more downpours make it harder to avert flooding and erosion on farms across the Midwest. California farmers, on the other hand, must find ways to stay productive despite increasing drought and wildfire risks.

It all amounts to far more than anecdotal inconvenience: The Intergovernmental Panel on Climate Change’s Fourth National Climate Assessment report projects that warming temperatures, severe heat, drought, wildfire, and major storms will “increasingly disrupt agricultural productivity,” threatening not only farmers’ livelihoods but also food security, quality, and price stability.

If these anticipated effects sound extreme, so too are the causes.

Five climate impacts affecting food production now

Climate change poses not just one but a whole slew of challenges to farmers – and to the larger communities that depend on them for food. From erratic precipitation to changing seasons, consider just these five key climatic changes and how they stand to affect food availability now and in the future:

1) More extreme weather can harm livestock and crops. Major storms have always devastated farms, whether from damaging winds during a storm, or erosion and landslides that can rear up even as the storm subsides. But now they’re becoming even more common. In spring 2018, for example, unusually heavy rain and snow storms caused massive flooding across the U.S. Midwest, leaving some areas 10 feet deep in sand. In Nebraska alone, farmers lost an estimated $440 million of cattle. As a result of these flooding conditions, many farmers had to delay spring planting. Delays in commodity crops like corn and soybeans aren’t just stressful for farmers, either – they could lead to food price volatility and even potential food insecurity.

2) Water scarcity across the U.S. Southwest makes it more expensive and difficult to sustain crops and livestock. Drought is in the long-term outlook across the U.S. West, with declining snowpack making it more challenging to keep reservoirs full through summer. Lack of adequate water can easily damage or destroy crops, dry up soil, and threaten livelihoods. Between 2014-2016, for example, California endured an estimated $3.8 billion of direct statewide economic losses to agriculture as a result of drought.

3) Seasons aren’t what they used to be. Growing seasons are starting earlier and getting hotter in a warming climate. A longer growing season, over time, could theoretically have some advantages, but it also presents more obstacles in the short term, such as an uptick in pest populations is possible, with more generations possible per year. Early spring onset can also cause crops to grow before the soil holds enough water and nutrients, or to ruin fruit crops that bud early and then experience later spring frost. Plus, warmer winters can affect other farming practices like grain storage.

Cornfield wildfire

Parched and fire-damaged ag fields pose mounting challenges to farmers and consumers.



Greta Thunberg is a painful reminder of decades of climate failures

Posted on 19 September 2019 by dana1981

This is a re-post from the Bulletin of the Atomic Scientists

This story is part of Covering Climate Now, a global collaboration of more than 300 news outlets to strengthen coverage of the climate story.

Sixteen-year-old Swedish climate activist Greta Thunberg has ignited the climate movement, most recently taking a zero-carbon ocean voyage to America to attend the September 23rd UN climate summit in New York City. She’s become so effective and inspiring that those who want to maintain the status quo—predominantly wealthy and powerful old white men—have begun to attack her. Greta has been called “the international mascot for climate alarmism … mentally unstable,” “a millenarian cult leader,” a “deeply disturbed messiah of the global warming movement,” a “teenage puppet,” a “petulant child,” and much more.

Greta articulated her views in a TEDx talk in which she accurately described the state of climate science and the fact that if we are to meet the Paris climate targets, developed countries in particular must rapidly reduce their carbon pollution. As Greta notes, the world has thus far failed to act, in part because most people don’t realize that rapid change is required.

But climate scientists have been warning about a potential climate crisis for decades, while the Silent Generation and Baby Boomers failed to act on those warnings. As a result, they frittered away the opportunity to transition away from fossil fuels with relative ease. Because of those decades of inaction, we now face a daunting task.

While some older Americans may “have no patience for teenagers who lecture adults,” Greta’s generation has every right to criticize them for endangering humanity’s future prosperity. Let’s examine the history of climate change warnings and missed opportunities.



Climate denier scientists think these 5 arguments will persuade EU and UN leaders

Posted on 11 September 2019 by dana1981

As reported by DeSmogUK, in an effort to derail European Union climate policies and international climate negotiations, hundreds of climate denier scientists have drafted a letter to be sent to leaders of EU and UN institutions. The letter outlines their case for why climate change isn’t an emergency, but it simply reheats several old and stale climate myths.

Although the letter is unlikely to achieve its goal of derailing climate negotiations and policies, since it represents the best case that climate deniers can make against the existence of a climate crisis, it’s worth examining the arguments therein.

Yes, humans are causing global warming

The first argument in the letter asserts that current global warming “is to be expected from the cyclic behavior of the climate system.”

No evidence is provided to support this claim or any other in the letter. In fact, the letter doesn’t even specify which cycle is purportedly responsible for the current global warming. That’s undoubtedly because there isn’t one. Earth’s temperatures are currently warming 20 to 50 times faster than when the planet exits an ice age, for example. No natural cycle can account for the current rapid global warming.

This is not a scientific argument; it’s just hand-waiving and magical thinking that climate scientists ruled out long ago.

Carbon pollution is harmful

The second point in the letter combines two myths:

“There is no proof that anthropogenic carbon dioxide (CO2) emissions are the major cause of global warming. There is also no scientific evidence that anthropogenic CO2 emissions have a detrimental effect on the quality of life.”

The use of the word “proof” here is a red flag. Science doesn’t operate by proofs; it operates by evidence, and there is overwhelming evidence that carbon pollution is the major cause of global warming. In fact, NASA climate scientists published a study in the prestigious journal Science in 2010 entitled “Atmospheric CO2: Principal Control Knob Governing Earth’s Temperature.” The latest IPCC report concluded with 95% confidence that humans are responsible for most global warming since 1950, and most likely responsible for all of it.

There is also overwhelming scientific evidence that carbon pollution has a detrimental effect on the quality of life through its amplification of extreme weather events like droughts, heatwaves, wildfires, floods, and hurricanes.

Climate models have been remarkably accurate

The third point in the letter argues,

“climate models have many shortcomings and are not remotely plausible as policy tools … they substantially overestimate the recent temperature increase.”

As I demonstrated in my book and in the video below, temperature predictions made by mainstream climate models have been remarkably accurate (unlike those made by deniers). Climate models are certainly among the scientific tools useful for policymaking, although we have enough evidence about the climate change risks we’re already experiencing even setting climate models aside.



Key facts about the new EPA plan to reverse the Obama-era methane leaks rule

Posted on 9 September 2019 by dana1981

This is a re-post from Yale Climate Connections

President Trump’s EPA is moving to roll back 2016 Obama administration methane leak regulations for key parts of the oil and gas industry, another example of what seems an across-the-board repudiation of Obama-era environmental and climate change initiatives. The new proposal, if made final, is certain to face legal challenges, with its ultimate fate perhaps being decided only by the administration in office in 2021.

EPA Administrator Andrew Wheeler in late August signed and later announced a proposed rule that would significantly weaken the methane leak reporting regulations. The proposed approach generally would allow transmission and storage sectors of the industry to self-regulate and self-report leaks of the highly-potent greenhouse gas.

In a prepared statement, Wheeler said “methane is valuable, and the industry has an incentive to minimize leaks and maximize its use.” He said that since 1990, “methane emissions across the natural gas industry have fallen by nearly 15%,” and that the new EPA approach “should not stifle this innovation and progress.” Separate rules on volatile organic chemicals “also reduce methane,” making the existing rule “redundant,” Wheeler argued.

Some large oil and gas companies, including BP, Exxon, and Shell, had voiced opposition to the new rules rollback.

But smaller companies and the industry’s principal trade association, the American Petroleum Institute, with more than 620 oil and gas company members, had pushed for weakening the methane regulations. They argue that mandated leak inspections are too costly and could make operation of small, often-leaky wells uneconomical. Wheeler appeared persuaded by these arguments, announcing that the new plan “removes unnecessary and duplicative regulatory burdens from the oil and gas industry” and will save fossil fuel companies around $100 million over the next six years.

The larger oil and gas companies appear to have opposed the new EPA move at least in part because their natural gas interests benefit from being seen as a climate-friendly alternative to coal, and a “bridge fuel” for the transition from coal to renewable energy.

But some scientific research has suggested that methane leakage from natural gas infrastructure such as fracking can erase much of its claimed climate benefits. For instance, authors of a 2018 study published in Science found that the amount of methane resulting from leaks exceeds by 60% the estimates made by EPA. “Considerable amounts of the greenhouse gas methane leak from the U.S. oil and natural gas supply chain,” the authors of that study wrote. They said the difference between EPA’s estimates and their own are the result of “current inventory methods [that] miss emissions that occur during abnormal operating conditions.”



IPCC's land report showed we're entering an era of damage control

Posted on 29 August 2019 by dana1981

The IPCC has published a new report on climate and land. The report includes chapters on land-climate interactions (land use changes are accelerating global warming, which is causing more extreme weather), desertification (deserts are expanding), land degradation (declining quality of soil, for example), and food security. The latter is a particularly critical topic, given our dependence on food and water supplies for survival.

The report notes that humans struggle to efficiently manage our food supply. Between 25 and 30 percent of the food we produce worldwide is wasted. This waste happens for different reasons in different regions – in developed countries, consumers throw out excess food, while in developing countries much of the waste is due to a lack of refrigeration as products go bad between producers and consumers. And of course refrigeration requires energy, meaning that mitigating the latter problem will generate more greenhouse gas emissions. The report estimates that food waste costs about $1 trillion per year and accounts for about 10 percent of greenhouse gas emissions from food systems. Meanwhile, 2 billion humans are overweight or obese while nearly 1 billion are undernourished, highlighting the inefficiencies and inequities in our food distribution.

Overall, 23 percent of human greenhouse gas emissions come from agriculture, forestry, and other land use. Much of this is due to emissions of the more potent greenhouse gases methane (from cattle and rice farming, for example) and nitrous oxide (from nitrogen-fertilized agricultural soils). The figure is comparable to the transportation sector (approximately 15 percent of total human greenhouse gas emissions) and electricity and heat (approximately 30 percent). The report notes that diets heavier in meat and particularly beef adversely impact both greenhouse gas emissions and health outcomes.

carbon footprints of various low-meat diets

Potential to reduce greenhouse gas emissions from changing diets by 2050, per the research cited in the IPCC report.



Millions of times later, 97 percent climate consensus still faces denial

Posted on 15 August 2019 by dana1981

A few weeks ago, the Bulletin ran a story referring to how Frank Luntz—the GOP message master who convinced party politicians to use the phrase “climate change” instead of “global warming” because the former sounded “less frightening”—is now offering his services to the cause of climate action. The idea that someone who had once crafted talking points defending some of the world’s worst carbon polluters had changed his tune to now advocate for “cleaner, safer, healthier” energy alternatives seemed to signal the dawn of a new era, right?

Not so fast.

In July, the Exxon- and Koch- funded Competitive Enterprise Institute (CEI) issued a formal complaint, asking NASA to “correct” a statement on the space agency’s website that said that “Multiple studies published in peer-reviewed scientific journals show that 97 percent or more of actively publishing climate scientists agree: Climate-warming trends over the past century are extremely likely due to human activities.”  In its complaint about NASA’s accurate statement, CEI cited 5-year-old disproved blog posts with titles like “1.6%, Not 97%, Agree that Humans are the Main Cause of Global Warming.” (It also cited conservative media outlets like ForbesNational Review, and the Daily Caller.)

So, what is the real percentage of climate researchers who agree that climate change is largely man-made? And what is the origin of the widely held perception among the American public that the science is still unsettled?

The numbers. By coincidence, also in July, a 2013 paper that I co-authored with my colleagues at Skeptical Science on the expert consensus about human-caused climate change in peer-reviewed literature was downloaded for the millionth time. In that study, our team examined the abstracts of nearly 12,000 peer-reviewed climate science studies published between 1991 and 2011, and categorized each one based on its position on the causes of global warming. In a second phase of our analysis we e-mailed the authors of each study and asked them to categorize their own papers using the same criteria, receiving 1,200 responses. Our team’s review of the abstracts yielded a 97.1 percent consensus that humans are primarily responsible for recent global warming; the author self-ratings yielded a 97.2 percent consensus.

Our analysis built upon a previous study published by Naomi Oreskes in the peer-reviewed journal Science in 2004. In her paper, which also just surpassed 1 million downloads, Oreskes examined the abstracts of 928 peer-reviewed climate papers published between 1993 and 2003. In her review, none of the abstracts disputed human-caused global warming. Not a single one out of 928. In 2016, our two groups teamed with the authors of five other climate consensus studies to publish a paper documenting the ‘consensus on consensus,’ in which we demonstrated that between 90 and 100 percent of climate scientists and their peer-reviewed research agree that humans are the main cause of recent global warming.



What role will climate change play in the 2020 presidential election?

Posted on 31 July 2019 by dana1981

This is a re-post from Yale Climate Connections

Journalists and political wonks have spilled lots of ink, and more recently lots of gigabytes, in presidential election runups speculating that the environment and global warming could become significant issues in voters’ minds. Seldom have their expectations been realized.

Are there reasons to think things might turn out differently in the 2020 presidential elections? Again, we’re hearing the familiar drumbeat – this time will be different.

Supporting that view is an early July Washington Post-ABC News poll that asked Americans whether they approve or disapprove of the Trump administration’s handling of nine important issues – the economy, immigration, taxes, health care, gun violence, foreign policy, abortion, climate change, and what the poll called issues of “special concern to women.”

Climate change received the most critical response, with 62% of Americans disapproving of the administration’s actions compared to just 29% approving.


That approval rate of “the way Trump is handling” climate change matches the 62 percent of Americans worried about the issue in a recent Yale-George Mason survey.*

The Trump administration has done nothing to address the carbon pollution causing the problem, and instead has exacerbated it. The administration began its campaign against Obama-era climate initiatives by announcing, soon after taking office, its intention to withdraw from the Paris climate agreement. Since then, the administration has moved to scrub mentions of climate change from government science press releases, has blocked climate-related congressional testimony from its intelligence agencies, has repealed the EPA Clean Power Planfrozen vehicle fuel efficiency standards, and undone dozens more regulations aimed at curbing pollutants.

Trump campaign staffers are reportedly concerned that the administration’s anti-environment agenda could hurt his re-election prospects among key constituencies, especially considering his “persistent unpopularity among female and suburban voters.” Compounding those concerns may be that the president’s approval rating hasn’t reached 50 percent during his time in office, making him the only president in the modern era never to have reached that milestone. Add in the “blue wave” midterm elections of 2018 in which Democrats regained a majority in the House of Representatives, and consider also Trump campaigners’ concerns over a mid-June Fox News poll that showed Trump trailing top Democratic presidential contenders.



The Trump EPA strategy to undo Clean Power Plan

Posted on 24 June 2019 by dana1981

This is a re-post from Yale Climate Connections

The Trump administration’s Environmental Protection Agency (EPA) on June 19 published its “Affordable Clean Energy” (ACE) rule to replace the Obama EPA’s Clean Power Plan (CPP).

The replacement plan is essentially the Trump administration’s attempt to adhere to the letter of the law mandating that carbon pollution be regulated, while requiring the smallest possible changes from the power utility industry. Preliminary research suggests that the ACE rule will barely reduce carbon emissions more than a scenario with no EPA policy whatsoever.

Current law says EPA must regulate carbon pollution

This story begins in 2003, when in response to a petition that the federal government regulate greenhouse gas emissions from motor vehicles, the George W. Bush EPA concluded that it did not have authority to do so under the Clean Air Act. Disagreeing with that determination, Democratic attorneys general of 12 states teamed up with several cities and environmental organizations to challenge that EPA action in court. The resulting litigation made it to the Supreme Court in 2007, and in the landmark Massachusetts v. Environmental Protection Agency ruling, the justices ruled 5-4 against the Bush administration and its EPA.

As a result, the agency was required to determine whether carbon dioxide and other greenhouse gases are air pollutants under the Clean Air Act, meaning that they “cause or contribute to air pollution which may reasonably be anticipated to endanger public health or welfare.”

In December 2009, EPA under President Obama completed its Endangerment Finding review of the scientific evidence and concluded that carbon pollution and other greenhouse gas emissions responsible for human-caused climate change clearly endanger public health and welfare. That determination led directly to the conclusion that the Clean Air Act requires that EPA regulate those pollutants, leading in turn to the Obama EPA’s CPP to strictly regulate utilities’ greenhouse gas emissions.

Emissions from motor vehicle tailpipes are addressed through corporate average fuel economy (CAFE) standards, which the Trump administration is also proposing to dramatically weaken in a battle with California and several other states, again all Democratically-controlled. To address pollution from power plants, the Obama EPA developed the CPP, which, if implemented, would have established national carbon emissions performance rates for coal and natural gas power plants while giving individual states some flexibility in finding ways to meet those standards.



In 1982, Exxon accurately predicted global warming

Posted on 19 June 2019 by dana1981

The Cato Institute, a Koch-founded and fossil fuel-funded think tank, has shut down its climate science-denying ‘Center for the Study of Science.’  The Center was led by Patrick Michaels, who has a long history of grossly misrepresenting climate science research, most notably in 1998 Congressional testimony during consideration of the Kyoto Protocol international climate agreement (which US Congress never ratified).  In that testimony, Michaels showed a version of James Hansen’s 1988 global temperature projections, but deleted the two scenarios in that study that most accurately represented real-world greenhouse gas emissions in order to create the misperception that Hansen had dramatically overestimated global warming.  That testimony could certainly be considered perjury, and yet Cato continued to employ Michaels for another 20 years.

ExxonMobil is on the list of Cato’s fossil fuel funders, but as Inside Climate News discovered, the company’s own scientists conducted serious climate research in the 1980s.  There was a stark contrast between Exxon’s own internal climate science research and the climate misinformation produced by the think tanks that the company subsequently funded.  To summarize,

  • In the early 1980s, Exxon’s own scientists accurately predicted the ensuing global warming to within a margin of 20%;
  • Exxon’s predictions were consistent with those made by mainstream climate scientists;
  • In the late 1980s, Exxon began funding think tanks whose scientists inaccurately predicted that temperatures would remain essentially unchanged;
  • These findings highlight the fact that Exxon knew about the dangers of global warming and yet quietly gave tens of millions of dollars to groups that tried to convince the public otherwise.



Humans and volcanoes caused nearly all of global heating in past 140 years

Posted on 30 May 2019 by dana1981

Emissions from fossil fuels and volcanoes can explain nearly all of the changes in Earth’s surface temperatures over the past 140 years, a new study has found.

The research refutes the popular climate denial myth that recent global warming is merely a result of natural cycles.

Those arguments have always suffered a key physical flaw, namely that cycles are cyclical. For example, El Niño events, which temporarily raise global surface temperatures by bringing warm water up to the shallow ocean layer, are offset by La Niña events, which have the opposite effect. While a given decade might have more El Niño or La Niña events, resulting in a short-term surface warming or cooling, over the long term their effects cancel out.

However, climate scientists have had a difficult time explaining exactly what caused a warming event in the early 20th century, between about 1910 and 1945. The average of the climate model runs incorporated in the last IPCC report only accounted for about half of the measured global surface warming trend during that period, and a study published last year suggested the other half could be due to natural cycles.

Contrarian scientists like Judith Curry, who is frequently invited by Republicans to testify before US Congress, have often used this discrepancy to cast doubt on the expert consensus on human-caused global warming, arguing that “until we can explain the early 20th century warming, I have little confidence IPCC and [National Climate Assessment] attribution statements regarding the cause of the recent warming.”

The new study, published in the Journal of Climate, tackles the discrepancy in part by addressing an issue with ocean temperature data during the second world war, when measurements were more often made from warmer engine room intakes than from buckets lowered over the side of ships. This has resulted in a bias, inflating estimated surface temperatures in the early-to-mid 1940s. The new study removed this bias by focusing on temperatures along continental and island coastlines.



Fox News made the US a hotbed of climate denial. Kids are the cure.

Posted on 9 May 2019 by dana1981

A new 23-country survey conducted by the YouGov-Cambridge Globalism Project found that America has the highest percentage of climate denial among first-world nations, behind only Indonesia and Saudi Arabia in all the countries surveyed. A total of 13 percent of Americans responded that “human activity is not responsible at all” for climate change, 5 percent denied that the climate is even changing, and a further 13 percent did not know whether the climate is changing or people are responsible.

These numbers are generally consistent with surveys conducted by George Mason and Yale universities, which most recently found in late 2018 that 14 percent of Americans think global warming isn’t happening, and 23 percent deny that it’s mostly human-caused.

The good news is that those 2018 numbers were at record low levels.

Climate denial in the United States appears to be shrinking.

In evaluating why climate denial is so much more prevalent in America than other wealthy countries, it’s important to consider its demographics. In the 2018 George Mason and Yale survey, just 42 percent of conservative Republicans accepted that global warming is happening, and only 28 percent correctly attributed it to human activities. Older Americans are also more likely to deny human-caused global warming, especially white Americans over the age of 55.



Climate change could cost the U.S. economy hundreds of billions a year by 2090

Posted on 30 April 2019 by dana1981

This is a re-post from Yale Climate Connections

A newly-published peer-reviewed analysis of climate change impacts across broad sectors of the U.S. economy provides what may be the most comprehensive economic assessment to date of those costs.

The April report in the journal Nature Climate Change is a condensed version of the Environmental Protection Agency’s 2017 Climate Change Impacts and Risk Analysis report. That analysis was used to help inform the Fourth National Climate Assessment Report published in late 2018.

Written by two EPA professional staffers – but with the standard caveat that it represents their views, and not necessarily those of the agency – the research addressed in the April report considers two global warming scenarios: Representative Concentration Pathway (RCP) 4.5 and 8.5, numbered to correspond to the global energy imbalance (in Watts per square meter) created by the increased greenhouse effect in the two scenarios.

RCP4.5 would lead to about 2.8°C (5°F) warming of global surface temperatures above pre-industrial levels by the year 2100. Limiting global warming to that degree would require more aggressive international climate policies than are in place today, but would nevertheless miss the 2015 Paris climate agreement targets of 2, and ideally of 1.5, degrees C. Continuing emission under the RCP8.5 approach would lead to about 4.5°C (8°F) warming by the end of the century, which is close to a worst-case scenario in which international policies do not slow global fossil fuel use and carbon pollution.

The Nature Climate Change analysis – by EPA scientists Jeremy Martinich and Allison Crimmins – examines 22 different climate economic impacts related to health, infrastructure, electricity, water resources, agriculture, and ecosystems. The bottom line conclusion: by the year 2090, impacts on those 22 economic sectors in the U.S. would cost about $224 billion more per year if we follow the RCP8.5 pathway than if we achieve the RCP4.5 pathway. The authors’ report comes with an important caveat:



Climate change poses security risks, according to decades of intelligence reports

Posted on 9 April 2019 by dana1981

This is a re-post from Yale Climate Connections

A series of authoritative governmental and nongovernmental analyses over more than three decades lays a strong foundation for concern over climate change implications for national security.

Most recently, the national intelligence community – including the Central Intelligence Agency, National Security Agency, Federal Bureau of Investigation, and other federal agencies – in January 2019 submitted the annual “Worldwide Threat Assessment.” In it, the intelligence agencies stated that “climate change is an urgent and growing threat to our national security, contributing to increased natural disasters, refugee flows, and conflicts over basic resources such as food and water. These impacts are already occurring, and the scope, scale, and intensity of these impacts are projected to increase over time.”

That report from National Intelligence Director Daniel R. Coats, a former U.S. Republican senator from Indiana, was just the most recent in a long string of analyses that any upcoming challenges to such conclusions will have to address. Those conclusions clearly are at odds with the Trump administration’s efforts to undermine and reverse federal climate policies, and they cast doubt on the President’s next day tweet that “Perhaps Intelligence should go back to school!”

With the White House now reportedly considering an executive order to establish a Presidential Committee on Climate Security that would contest such findings, it’s useful to review the history of climate change/national security official reports and findings. Although it’s unclear where the internal White House thinking on such a committee will lead, it’s been authoritatively reported that the push for such an effort is led by two individuals – Will Happer and Steven Koonin – widely known to have climate change views far different from those of the “established” science community as represented, for instance, by IPCC and the National Academy of Sciences.

Former Princeton physicist Will Happer, now with the White House staff, has a long history of scientifically challenged views about climate science. In the past a frequent favorite witness before House hearings overseen by members rejecting the climate science community “consensus,” Happer has acknowledged in a court case receiving funding from Peabody Coal and from other fossil fuel interests. In 2015 the New York Times reported that he was caught in a Greenpeace “sting” agreeing to take money from unknown Middle Eastern oil and gas interests in exchange for writing a report challenging climate science. Steven Koonin has written on blogs and in the Wall Street Journal pieces in stark contrast to the view of the overwhelming scientific consensus.

Concerned about reports of a potential new presidential review of climate change and national security, 58 former military and intelligence officials on March 5 sent a letter to the president cautioning that “imposing a political test on reports issued by the science agencies, and forcing a blind spot onto the national security assessments that depend on them, will erode our national security.”



Protecting oil companies instead of the climate-vulnerable is elitist

Posted on 2 April 2019 by dana1981

This is a re-post from the Bulletin of the Atomic Scientists

At a recent House congressional hearing on legislation aimed at addressing homelessness, Rep. Sean Duffy, a Wisconsin Republican, introduced an amendment aimed at demonstrating how addressing climate change could increase the cost of housing. In the hearing Duffy said, “We talk about how we care about the poor, but all the while we’ll sign bills that dramatically increase the cost of a family to get into a home” during his criticism of the cost of a Green New Deal. He continued:  “…[R]ich, wealthy elites who will look at this and go, ‘I love it, because I’ve got big money in the bank; everyone should do this. We should all sign onto it.’ But if you’re a poor family, just trying to make ends meet, it’s a horrible idea.”

The great irony is that poor families are the most vulnerable to the impacts of climate change. They have the fewest resources available to adapt or recover when struck by a climate-amplified hurricane or wildfire or flood. One study found that nearly half of the low-income parents affected by Hurricane Katrina experienced post-traumatic stress disorder. Poorer developing countries are also the most vulnerable to climate change because of their lack of resources and because they tend to be nearer the equator where temperatures are already hot. Research has shown that countries with more temperate climates like the United States and Europe are near the peak temperature for economic activity. Poorer tropical countries are already hotter than optimal, so additional warming hits them particularly hard.

Surveys have also shown that minorities in America are more concerned about climate change and more supportive of climate policies, likely in part because they are more likely to live in close proximity to coal power plants. Poorer households living near these sources of air and water pollution would directly benefit from climate policies that accelerate the transition away from dirty fossil fuels toward clean energy. And as Rep. Alexandria Ocasio-Cortez, a New York Democrat, noted in her viral response to Duffy, millions of Puerto Ricans were severely impacted and thousands killed by Hurricane Maria. A year-and-a-half later, the island is still struggling to recover and is now facing a food stamp crisis.

Calling climate policy efforts “elitist” is thus completely backwards, especially when considering that opposition to such policies mostly benefits oil companies, many of which are among the most profitable in the world.

That said, there are valid concerns about the financial impacts of climate policies on lower income households. Policies such as a tax on carbon pollution would raise energy prices, and lower-income households spend a relatively large percentage of their incomes on energy. A smart climate policy should take these effects into account.

For example, the Energy Innovation and Carbon Dividend Act would offset the effects of a carbon tax by rebating the revenue equally to all American households. Because wealthier individuals have a bigger carbon footprint and because the revenue would be rebated equally to all Americans, a study of the bill’s impacts found that it would generate net revenue for 86 percent of the poorest households, whose dividend checks would be larger than their increased energy costs.



What's in the Green New Deal? Four key issues to understand

Posted on 27 February 2019 by dana1981

In the few weeks since it was introduced as a non-binding resolution before the U.S. Senate and House of Representatives, the Green New Deal (GND) Resolution has generated more discussion and coverage of climate change – positive and negative – among, by, and aimed at policymakers than we’ve seen in more than a decade.

The nonbinding initiative introduced by Rep. Alexandria Ocasio-Cortez (D-NY) and Edward Markey (D-MA) proposes embarking on a 10-year mobilization aimed at achieving zero net greenhouse gas emissions from the United States. The mobilization would entail a massive overhaul of American electricity, transportation, and building infrastructure to replace fossil fuels and improve energy efficiency, leading some to call it unrealistic, idealistic, politically impossible, and “socialistic.”


Proponents of GND portray it as an early focus for meaningful climate policy discussion if political winds lead to changes in 2020 for the presidency and the Senate majority. They say the GND is the first proposal to grasp the scale and magnitude of the risks posed by the warming climate. And while begrudgingly accepting the insurmountable odds against full enactment before 2021 at the earliest, they see it as a worthwhile and long-overdue discussion piece.

Many commentators and policy analysts argue that the changes it calls for would be too expensive, radical, and disruptive. Others have argued that anyone who doesn’t support this sort of emergency transition away from fossil fuels is in denial about the magnitude of the climate problem. Many are confused about the Resolution’s vague contents, in part because Ocasio-Cortez’s office also released an inaccurate fact sheet that subsequently had to be retracted. That document provided early and low-hanging targets for those disposed to wanting to dampen GND enthusiasm.



Earth’s oceans are routinely breaking heat records

Posted on 4 February 2019 by dana1981

Two recently published peer-reviewed studies make clear that the planet’s oceans are continuing to set hottest-yet temperature records nearly every year and, secondly, that the rate of ocean warming is in virtual lockstep with what modern climate models have projected.

Taken together, the findings, from studies led by Lijing Cheng of the Chinese Academy of Sciences Institute for Atmospheric Physics, demonstrate that climate scientists have developed an increasingly clear picture of the rapid warming of Earth’s oceans and its consequences.

One study, led by Cheng and colleagues and published in Advances in Atmospheric Sciences, concludes that 2018 was the hottest year ever recorded in the oceans. In fact, since the turn of the century, all but three years – 2007, 2010, and 2016 – have set a new ocean heat record.

Those three exceptions shared a key trait: Each was characterized by significant El Niño events, which transfer heat from the ocean to the air. As a result, for heat at Earth’s surface (in the air above both the land and oceans), 2007 was the second-hottest year up to that time, and 2010 and 2016 both subsequently broke the surface temperature record. 2018 was the fourth-hottest on record at the surface as a result of a La Niña event that year that kept more heat in the oceans than was the case in 2015 through 2017.

About 93 percent of global warming goes into heating the oceans, compared to about 2 percent warming the atmosphere. As the hottest year in the oceans, 2018 therefore was the hottest year ever recorded for the planet as a whole. And the amount of heat currently building up on Earth is equivalent to the amount of energy released by more than five atomic bomb detonations per second, every second.

What’s it all mean?



A Green New Deal must not sabotage climate goals

Posted on 31 January 2019 by dana1981

Recently, 626 organizations—mostly environmental groups, including and Greenpeace USA—sent a letter to Congress urging lawmakers to consider a number of principles when crafting climate legislation like a Green New Deal “to keep global warming below 1.5 degrees Celsius (2.7 degrees Fahrenheit).” Broadly, there were six major principles in the letter: Halt all fossil fuel leasing, phase out all fossil fuel extraction, end fossil fuel and other dirty energy subsidies; transition power generation to 100 percent renewable energy; expand public transportation and phase out fossil-fuel vehicles; harness the full power of the Clean Air Act; ensure a just transition led by impacted communities and workers; and uphold indigenous rights.

These are generally wise goals, but some concerns about the details caused eight major environmental groups—including the Sierra Club, the Natural Resources Defense Council, and the Environmental Defense Fund—to decline to sign the letter. As one national environmental group spokesperson put it, “the details matter… There is some language that gave us some concern.”

To meet climate targets, we need every tool in the chest. Meeting the Paris climate agreement targets of limiting global warming to less than 1.5 degrees Celsius of global warming above pre-industrial temperatures—or even a more dangerous but more feasible 2 degrees Celsius—would require massive and immediate global action to reduce fossil fuel consumption and carbon pollution. Simply put, we’ve already burned through so much of our carbon budget that meeting those targets would take everything we’ve got. (We’ve already locked ourselves in to close to 1.5 degrees Celsius of warming, just based on greenhouse gas emissions to date.)

But the letter includes language that rules out some zero-carbon technologies. For example, it states, “in addition to excluding fossil fuels, any definition of renewable energy must also exclude all combustion-based power generation, nuclear, biomass energy, large scale hydro and waste-to-energy technologies. To achieve this, the United States must shift to 100 percent renewable power generation by 2035 or earlier.”



Republicans call for 'innovation' to tackle climate change, but it's not magic

Posted on 8 January 2019 by dana1981

Limiting global warming to less than the Paris Climate Agreement target of 2°C (3.6°F) hotter than pre-industrial temperatures will require a rapid global transition away from fossil fuels. That’s a point on which the scientific community strongly agrees.

If we start now, we need to cut global carbon pollution by about 5 percent per year to avoid burning through our remaining “carbon budget”. Since 2012, emissions have gone up about 1 percent per year on average. That was an improvement on the 3 percent rise per year from 2000 to 2011, but global carbon emissions rose by about 2.7 percent in 2018.

In the USA, emissions had been falling by about 0.5 percent per year since 2000 and 1 percent per year since 2010, but they rose by about 2.5 percent in 2018. Basically, the U.S. is making some progress in decarbonizing, thanks primarily to wind, solar, and natural gas replacing more expensive coal power plants, but it’s not happening nearly fast enough to stay within our carbon budget.

That point was made especially clear when the IPCC published its special report on the difference between 1.5 and 2°C (2.7 and 3.6°F) and the Fourth National Climate Assessment report was published soon thereafter. Journalists asked numerous policymakers what they propose to do to address the problem, and surprisingly, many Senate Republicans accepted the scientists’ findings and the need for solutions. Their answers tended to share a common thread:



2018 was the hottest La Niña year ever recorded

Posted on 24 December 2018 by dana1981

Once the final official global annual surface temperature is published, 2018 will be the hottest La Niña year on record, by a wide margin. It will be the fourth-hottest year overall, and the fourth consecutive year more than 1°C (1.8°F) hotter than temperatures in the late-1800s, when reliable measurements began. 2009 will be bumped to second-hottest La Niña year on record, at 0.87°C (1.6°F) warmer than the late-1800s, but about 0.16°C (0.29°F) cooler than 2018.

The above brief visual uses NASA GISS global average surface temperature data for 1970–2018, splitting the period into El Niño, Neutral, and La Niña years with linear trends. (Video by Dana Nuccitelli)

El Niño events bring warm water to the ocean surface; La Niña events are cool at the surface. Since scientists measure global surface temperatures over both land and oceans, new hottest year records are usually set during El Niño events.

For this reason, it’s best to compare like-with-like. In the case of 2018, given that it was a La Niña year, it’s most useful to compare it with prior years in which global surface temperatures were cooled by La Niña events.

El Nino / La Nina tempsNASA GISS global average surface temperature data for La Niña years during the period 1970–2018. (Illustration by Dana Nuccitelli)



Dana on Warm Regards Podcast

Posted on 19 December 2018 by dana1981

Dana was a guest on the latest episode of Warm Regards.  Take a listen.



Little Ice Age? No. Big Warming Age? Yes.

Posted on 18 December 2018 by dana1981

In September, a website called Space Weather Archive interviewed Martin Mlynczak of NASA’s Langley Research Center. Mlynczak noted that because the sun is currently in a relatively inactive period, the thermosphere (one of the highest layers of Earth’s atmosphere, more than 300 miles above the surface) could reach its coldest temperatures since records began in the 1940s.

The interview didn’t mention Earth’s surface temperatures, where the past five years have been the five hottest since records began in the late-1800s. However, the British newspaper Metro then ran a story falsely claiming that: “It’s feared this could herald the arrival of a uniquely grim ‘mini Ice Age.’ ”

Like a bad game of Telephone, this inaccurate reporting then spread throughout the conservative media, including Fox News, the Drudge Report, Rush Limbaugh, and Sarah Palin’s Twitter page. The story was debunked by the climate scientists at Climate Feedback, and Metro subsequently issued a correction, but the damage had been done.

The ‘imminent mini ice age’ myth rears its ugly head in the conservative media like clockwork every year or two. It’s always based on claims that the sun is headed into an inactive phase, like those that coincided with what has popularly been called the “Little Ice Age”—the period from roughly about the 16th to 19th centuries when some exceptionally cold winters made the Thames River sometimes freeze so solidly that Londoners held winter fairs on the ice, and contemporary diarists wrote that the snow was so deep in New Hampshire that people burned their furniture because they couldn’t get to the woodshed. (“…[O]ur last Winter brought with it a Snow that excelled them all,” wrote Cotton Mather wrote in his diary in 1717, under the heading “An Horrid Snow.”) But the term Little Ice Age is a misnomer, and some climate scientists have argued that the name should be abandoned. It was not a full-blown ice age at all (or even a little one), but rather a very short-lived and puny climate and social perturbation, by the standards of geologic time.

Not headed for another grand solar minimum

It’s true that the sun is in a relatively quiet period, with the amount of energy reaching the Earth (Total Solar Irradiance, or TSI) lower than it has been since the mid-1900s. But TSI is still significantly higher than it was during the so-called Little Ice Age, and likely higher than at any time between the 1600s and 1940, for that matter. Particularly during the late-1600s, there was a period when only about two sunspots were observed per year. (Sunspots are an indicator of solar activity). Scientists coined this type of period a “grand solar minimum.” For comparison, in 2018 there have been about 50 sunspots observed.



Like health care, climate policy could tip elections

Posted on 11 December 2018 by dana1981

In the November 2018 midterm elections, Democrats won the U.S. House of Representatives popular vote by a margin of about 8.6 percent and gained 40 seats in that chamber. For perspective, President Obama won his convincing 2008 and 2012 elections by 7.2 percent and 3.9 percent, respectively. While Republicans increased their Senate hold in 2018 by two seats and strengthened their majority control, they won races only in states that had voted for Donald Trump for President in 2016, and Republican Senate candidates lost races in eight states that Trump had won.

It was a decisive “Blue Wave” election, and when asked what they considered the most important issue in exit polls, 41 percent of voters listed health care, and three-quarters of those voted for Democrats. That was the issue Democrats campaigned most heavily on in 2018, and it helped sweep them back into power in the House. And some eerie similarities are emerging between health care and climate change in the American political landscape.

Republicans have rejected compromise

When the Obama administration took office in 2009, its three highest priorities were passing a stimulus package to pull America out of the Great Recession, implementing health care reform, and tackling climate change. President Obama set out to negotiate with congressional Republicans on all three.

For example, Obama agreed to a much smaller stimulus than he earlier had wanted, and one that was significantly cheaper than the tax cut Republicans passed in 2017 during strong economic conditions.

On health care, Democrats – albeit often with reluctance and only in the face of insurmountable opposition – cast aside their preference for universal health care or even a public option. They lent support instead to a more conservative policy based on “Romneycare,” named after 2012 Republican presidential nominee Mitt Romney’s approach in Massachusetts. (Romney in November was elected to the U.S. Senate from Utah.) Despite Democrats’ efforts to seek a health care compromise, no Senate Republicans voted for the legislation, and congressional Republicans subsequently tried 70 times to repeal, modify or otherwise curb the Affordable Care Act.

With that history, many Democrats appear to have grown tired of trying to protect Obamacare as it now stands, and party leaders are lending support to some version of Medicare-for-all.

In short, Republican lawmakers rejected a conservative health care policy solution, and they have been unable to come up with and pass a preferred alternative. Their constituents’ concerns over health care cost many congressional Republicans in the 2018 elections. And now they see an incoming Democratic majority in the House, come January 3, embracing a more liberal government-based policy approach over the more market-based compromise solution.



Trump's disbelief won't stop dangerous climate change

Posted on 5 December 2018 by dana1981

“I don’t believe it,” said Donald Trump when asked about the fourth national climate assessment, authored by 13 government agencies and hundreds of the US’s top climate scientists. His administration had tried to hide the report, publishing it on Black Friday when many Americans were either recovering from a Thanksgiving food coma or stampeding department store sales.

The administration’s plan backfired badly – the latest alarming climate science report became front-page news. Numerous Republican politicians were asked about it on TV news and politics shows, and their answers demonstrated that Trump’s climate science denial continues to pervade the GOP.

Republican party leaders’ answers ranged from platitudes – such as “our climate always changes” and “innovation” is all that is needed to solve the problem – to accusations that “a lot of these scientists are driven by the money”.

Addressing the latter point, one of the report’s lead authors, Prof Katharine Hayhoe, noted that many of its contributors were “paid zero dollars” and estimated that in the time she devoted to the assessment, she could have written eight of her own papers. Conversely, GOP politicians and operatives are paid millions of dollars annually by the fossil fuel industry. Some people are clearly driven by the money, and it’s not climate scientists.

Trump’s comments did not stop at disbelief – he also appeared to shift blame to other countries and tout the US’s clean air and water.



The many ways climate change worsens California wildfires

Posted on 14 November 2018 by dana1981

This is the first entry in a Dana's new monthly column with Yale Climate Connections

NASA photoNow designated as California’s deadliest fire, the still-raging Camp Fire by November 13 had led to 42 deaths, with many residents still unaccounted for and more than 7,000 structures destroyed. (Image credit: NASA)

California has been ravaged by record wildfires in recent years. 2017 was the state’s costliest and most destructive fire season on record. The Mendocino wildfire in July 2018 was California’s largest-ever by a whopping 60 percent.

Even though California’s wildfire season has traditionally ended in October, the Camp Fire raging in November 2018 is the state’s most destructive on record.

The data tell the story: Six of California’s ten most destructive wildfires on record have now struck in just the past three years.

President Trump’s tweets suggesting forest mismanagement is to blame for California’s wildfire woes, and threatening to withhold federal funding, have prompted widespread rebukes for their insensitivity as thousands of citizens flee the fires – some, tragically, unsuccessfully – and as an affront to thousands of weary firefighters.

The reality is that about 57 percent of the state’s forests are owned and managed by the federal government, and another 40 percent by families, companies, and Native American tribes. Forest management does play some role in creating wildfire fuel, but some wildfires aren’t even located in forests. Moreover, scientific evidence clearly shows that climate change is exacerbating California’s wildfires in different ways:

  • Higher temperatures dry out vegetation and soil, creating more wildfire fuel.'
  • Climate change is shortening the California rainy season, thus extending the fire season.
  • Climate change is also strengthening the Santa Ana winds that fan particularly dangerous wildfires in Southern California.
  • The warming atmosphere is slowing the jet stream, leading to more California heat waves and high-pressure ridges in the Pacific. Those ridges deflect from the state some storms that would otherwise bring much-needed moisture to slow the spread of fires.



What are the climate change consequences of the midterm elections?

Posted on 12 November 2018 by dana1981

This is a re-post from the Bulletin of the Atomic Scientists

Over the past two years, the Trump administration, aided by the Republican-controlled Congress, has eroded the Obama administration’s policy efforts to curb global warming. Climate activists had hoped to reverse some of those losses in this year’s midterm elections, but the results were a mixed bag. Here is the rundown of where we stand.

What can House Democrats do with the majority? 

The Democrats won control of the House of Representatives and will hold about 232 seats (53 percent) starting in 2019. This gives them control over legislation in that chamber of Congress. Democrats will become House committee chairs, who choose the bills that receive a hearing and a vote in a given committee. Democrats will also be able to choose the Speaker of the House – likely to be Nancy Pelosi – who decides what bills come to the floor for a vote after they’ve passed out of committees.

We’re thus in a similar scenario as in 2009, when House Democrats led by Nancy Pelosi passed the American Clean Energy and Security Act carbon cap and trade bill. At that time, Democrats had a majority in the Senate, but not a 60-vote supermajority. Because the bill lacked the votes to defeat a Republican filibuster, it was never brought to the Senate floor for a vote. Republicans now hold the Senate and White House, so climate legislation has no chance of passing until either Democrats take control of those branches (and overcome a Senate filibuster), or a significant number of Republican lawmakers stop denying the need to address the existential threat posed by climate change.

In the meantime, Democrats can now play a major role in setting the federal budget, which means they can protect funding for climate science research and for federal agencies like the EPA. So, we can at least keep learning about the dangers posed by climate change as the Trump administration tries to increase the carbon pollution that’s creating those threats. The House Science Committee will now be controlled by Democrats rather than some of Congress’ worst science-denying Republicans like Lamar Smith (retired) and Dana Rohrabacher (defeated), and thus will thankfully no longer hold theatrical hearings to deny basic climate science.



A eulogy to Guardian's Climate Consensus - the 97%

Posted on 30 October 2018 by dana1981

The Guardian editors recently decided to discontinue their Science and Environment blog networks.  This is the story of Climate Consensus - the 97%.

Way back in 2012, newspapers were struggling to hang on to readers. Blogs were all the rage, and with the stability of the Obama administration, a steadily improving economy, the UK still in the EU (how I long for those good old days), there wasn't today's demand for daily newspapers. Papers were trying to come up with new ideas, and the Guardian editors decided to experiment with international blog networks.

It was a very clever idea. There were lots of smart science and environment bloggers out there, writing on their own blogs for free. By folding them into The Guardian, the paper was able to add their expert analysis. By splitting the ad revenue, they guaranteed some profit for the paper while bringing in new readers for the expert analysis, and the bloggers who previously wrote for free got a bit of pay for their work, plus the prestige of affiliation with The Guardian. It was a win-win.



Canada passed a carbon tax that will give most Canadians more money

Posted on 29 October 2018 by dana1981

Note: this will be our final entry on Climate Consensus - the 97%. The Guardian has decided to discontinue its Science and Environment blogging networks. We would like to thank this great paper for hosting us over the past five years, and to our readers for making it a worthwhile and rewarding endeavor.

Last week, Prime Minister Justin Trudeau announced that under the Greenhouse Gas Pollution Pricing Act, Canada will implement a revenue-neutral carbon tax starting in 2019, fulfilling a campaign pledge he made in 2015.

The federal carbon pollution price will start low at $20 per ton in 2019, rising at $10 per ton per year until reaching $50 per ton in 2022. The carbon tax will stay at that level unless the legislation is revisited and revised.

This is a somewhat modest carbon tax – after all, the social cost of carbon is many times higher – but it’s a higher carbon price than has been implemented in most countries. Moreover, a carbon tax doesn’t necessarily have to reflect the social cost of carbon. The question is whether it will be sufficiently high to meet the country’s climate targets.

Paris was a key motivator behind the Canadian carbon tax

The Preamble in the Act is worth reading. It begins by noting “there is broad scientific consensus that anthropogenic greenhouse gas emissions contribute to global climate change” (this is somewhat understated – carbon pollution is the dominant factor). It also notes that Canada is already feeling the impacts of climate change through factors like “coastal erosion, thawing permafrost, increases in heat waves, droughts and flooding, and related risks to critical infrastructures and food security.”

The Preamble also notes that in 1992, Canada signed the UNFCCC whose objectives include “the stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system,” and that Canada ratified the Paris Agreement, whose aims include limiting global warming to less than 2°C above pre-industrial temperatures.

Canada’s Paris commitment requires cutting its carbon pollution by 30% below 2005 levels by 2030. Prior to the implementation of the carbon tax, its policies were rated Highly Insufficient to meet that goal. Instead Canada’s emissions were on track to fall only about 4% below 2005 levels by 2030. So, the carbon tax is an important policy to close that gap.



Trump thinks scientists are split on climate change. So do most Americans

Posted on 22 October 2018 by dana1981

When queried about the most recent IPCC report, Republican lawmakers delivered a consistent, false message – that climate scientists are still debating whether humans are responsible. The previous IPCC report was quite clear on this, attributing 100% of the global warming since 1950 to human activities. As Nasa atmospheric scientist Kate Marvel recently put it, “We are more sure that greenhouse gas is causing climate change than we are that smoking causes cancer.”

Donald Trump articulated the incorrect Republican position in an interview on 60 Minutes:

We have scientists that disagree with [human-caused global warming] … You’d have to show me the [mainstream] scientists because they have a very big political agenda

To paraphrase, ‘I know scientists. I have the best scientists.’ And of course Trump thinks he has “a natural instinct for science” which, as astrophysicist Katie Mack noted, is not a thing:

Katie Mack@AstroKatie

There is no "natural instinct for science." This is not a thing. There is curiosity, there is exploration, and there is the desire to learn & grow & test one's naive notions against cold hard data. Believing in a "natural instinct for science" is anathema to everything science is

Americans badly underestimate the expert climate consensus

Numerous papers have shown that over 90% of climate science experts agreethat humans are the main cause of global warming since 1950, and when considering peer-reviewed papers, the consensus exceeds 97%.

And yet as surveys by Yale and George Mason universities have found, only about 15% of Americans are aware that the expert climate consensus exceeds 90%. More recently, the Yale and George Mason team broke down American’s perceived expert consensus by their ‘Six Americas’ categorizations:



Republican lawmakers react to the IPCC report – ‘we have scientists’ too!

Posted on 17 October 2018 by dana1981

Major climate science reports usually pass by largely unnoticed, but in the wake of the latest IPCC report a number of journalists laudably grilled Republican lawmakers about its findings. While their responses were predictably terrible, it’s nevertheless crucial for journalists to hold GOP politicians accountable for their climate denial and policy inaction. Donald Trump’s answers were particularly ignorant and nonsensical in his 60 Minutes interview with Lesley Stahl.

Welcome to Stage 2 climate denial

None of the Republicans exhibited Stage 1 climate denial (denying that it’s happening), but several remain in Stage 2 (denying humans are responsible). Trump was the worst of the lot, telling Stahl:

Something’s happening [with the climate] and it’ll change back again … I don’t know that it’s manmade.

Earth’s climate isn’t magical. Each of its changes has physical causes and will only “change back” if something causes them to do so. Trump’s claim is akin to arguing that if he gains 50 lbs by eating McDonald’s fast food every day he’ll eventually ‘change back’ to his less obese self. Doing so would require a physical cause, like a change in diet. Fossil fuels are the climate’s greasy fast food.

Similarly, Trump’s top economic advisor Larry Kudlow said to George Stephanopoulos on ABC’s This Week:

how much of [climate change] is manmade, how much of it is solar, how much of it is oceanic, how much of it is rain forest and other issues? I think we’re still exploring all of that.

And Senator Marco Rubio (R-FL) told CNN’s Jake Tapper:

I can’t tell you to what percentage of [climate change] is due to human activity

Climate scientists can. It’s 100% since 1950.

Gavin Schmidt@ClimateOfGavin

For @marcorubio @jaketapper and anyone else, it’s a good thing that scientists have indeed already looked at how much recent trends in climate are due to human activity. 

[narrator: it was all of it]

This is settled science, about which there’s a 97% expert consensus. But of course, Republican politicians prefer the beliefs of the less than 3% of contrarian climate scientists.



There’s one key takeaway from last week’s IPCC report

Posted on 15 October 2018 by dana1981

The Paris climate agreement set a target of no more than 2°C global warming above pre-industrial temperatures, but also an aspirational target of no more than 1.5°C.  That’s because many participating countries – especially island nations particularly vulnerable to sea level rise – felt that even 2°C global warming is too dangerous.  But there hadn’t been a lot of research into the climate impacts at 1.5°C vs. 2°C, and so the UN asked the IPCC to publish a special report summarizing what it would take to achieve the 1.5°C limit and what the consequences would be of missing it.

The details in the report are worth understanding, but there’s one simple critical takeaway point: we need to cut carbon pollution as much as possible, as fast as possible.

We’re about to burn through the 1.5°C carbon budget

Depending on how we define ‘pre-industrial temperatures’ and how fast we keep consuming fossil fuels, we’ll likely burn through the rest of the 1.5°C carbon budget within the next 3 to 10 years.  To stay below 1.5°C, the IPCC therefore concludes the world must embark on a World War II-level effort to transition away from fossil fuels, and also start removing carbon dioxide from the atmosphere at large scales – anywhere from 400bn to 1.6tn tons of it.


 Global carbon dioxide emissions to date, and potential pathways to stay within the remaining 1.5°C global warming budget. Illustration: IPCC SR15



The Trump administration has entered Stage 5 climate denial

Posted on 8 October 2018 by dana1981


A cartoon illustration of the Trump administration’s climate policy logic Illustration: John Cook

Several years ago, I wrote about the five stages of climate denial.  To date, the Trump administration has pinballed between Stages 1, 2, and 3, calling climate change a Chinese hoaxdisputing the degree of human causation (100% since 1950), and claiming it’s not a threat.  But the purpose of climate science denial is to obstruct climate policies, and science denial doesn’t hold up in court.  Unlike in the political realm, judicial decisions are generally based on evidence. 

The Trump administration wants to roll back the Obama administration’s increased vehicle fuel efficiency standards.  But under the National Environmental Policy Act (NEPA), “if a proposed major federal action is determined to significantly affect the quality of the human environment,” the agency has to publish an environmental impact statement (EIS).


Vehicle fuel efficiency standards to date (blue) and required under the Obama administration rules (green) and the Trump administration’s proposal (red) Illustration: National Highway Traffic Safety Administration

And so, the National Highway Traffic Safety Administration (NHTSA) was required to publish an EIS detailing how the proposed fuel efficiency rollbacks would impact the environment, including via climate change.  Here, the Trump administration shifted to Stage 4 and 5 climate denial.



New study finds incredibly high carbon pollution costs – especially for the US and India

Posted on 1 October 2018 by dana1981

The social cost of carbon is a measure of the economic damages caused (via climate change) by each ton of carbon pollution that we produce today.  It’s difficult to estimate because of physical, economic, and ethical uncertainties.  For example, it’s difficult to predict exactly when various climate tipping points will be triggered, how much their damages will cost, and there’s also a question about how much we value the welfare of future generations (which is incorporated in the choice of ‘discount rate’).

In 2013, the Obama administration set the federal social cost of carbon estimate at $37 per ton of carbon dioxide (up from the previous estimate of $22).  That was a conservative estimate – in recent years, research has pegged the value closer to $200 because recent research has shown that global warming slows economic growth, which makes it quite expensive.  A majority of economists in a 2015 survey believed the federal estimate was too low, but Republicans have recently been trying to dramatically lower it anyway.

The Republican argument is twofold.  First, that we should only consider domestic climate costs (the federal estimate is of global costs, because our carbon pollution doesn’t just hover in the air above America).  Second, that instead of trying to stop climate change now, we should just save our money and let future generations pay for its costs (by using a high discount rate).

The social cost of carbon is much higher yet

A new study led by UC San Diego’s Katharine Ricke published in Nature Climate Change found that not only is the global social cost of carbon dramatically higher than the federal estimate – probably between $177 and $805 per ton, most likely $417 – but that the cost to America is around $50 per ton.  That’s the second-highest in the world behind India’s $90, and is also higher than the current federal estimate for the global social cost of carbon.

That’s a remarkable conclusion worth repeating.  Ricke’s team found that the cost of carbon pollution to just the United States is probably higher than its government’s current estimate of costs to the entire world.  And the actual global cost is more than 10 times higher than the federal estimate.  And yet Republican politicians think that estimate should be much lower.



New study reconciles a dispute about how fast global warming will happen

Posted on 24 September 2018 by dana1981

We’re currently on pace to double the carbon dioxide-equivalent (including other greenhouse gases) in the atmosphere by around mid-century.  Since the late 1800s scientists have been trying to answer the question, how much global warming will that cause?

In 1979, top climate scientists led by Jule Charney published a reportestimating that if we double the amount of carbon dioxide in the atmosphere from pre-industrial levels of 280 ppm to 560 ppm, temperatures will warm by 3 ± 1.5°C.  Four decades later, ‘climate sensitivity’ estimates remain virtually unchanged, but some climate contrarians have argued that the number is at the low end of that range, around 2°C or less.

It’s an important question because if the contrarians are right, the 2°C resulting global warming would represent significantly less severe climate change consequences than if mainstream climate scientists are right and temperatures rise by 3°C.  It would also mean our remaining carbon budgetfor meeting the 2°C Paris target is about twice as large than if the mainstream consensus is right.  If the consensus is correct, we’re on pace to blow through the remaining Paris carbon budget by around 2030.

Another nail in the contrarian ‘low sensitivity’ coffin

Studies published in March 2014May 2014, and December 2015 identified two critical flaws in the contrarians’ preferred so-called ‘energy balance model’ approach: it doesn’t account for the fact that Earth’s sensitivity can change over time, for example as large ice sheets continue to melt, or that the planet responds differently to different climate ‘forcings’.

Last week, the journal Earth’s Future published a study by the University of Southampton’s Philip Goodwin that took both of these factors into account.  Goodwin ran climate model simulations treating every forcing separately, including changes in greenhouse gases, solar activity, particulates from volcanic eruptions, and from human fossil fuel combustion.  For each, he included feedbacks from changes in factors like atmospheric water vapor, clouds, snow, and sea ice, including how these factors change over different timescales, as Goodwin explained:



California plans to show the world how to meet the Paris climate target

Posted on 17 September 2018 by dana1981

Last week, California Governor Jerry Brown signed State Senator and US Senate candidate Kevin de León’s SB 100, which mandates that the state obtain all of its electricity from zero-carbon sources by 2045. That in itself was a big deal, but Brown didn’t stop there; he also issued an executive order calling for the entire California economy to become carbon-neutral by 2045. That’s a huge deal.

In order to stay below the Paris climate threshold of 2°C global warming above pre-industrial temperatures, humanity must become carbon-neutral by around 2060 or 2070. If California can meet Brown’s target, it will be providing the rest of the world a blueprint for meeting the Paris target. As the world’s fifth-largest economy, California can provide a powerful roadmap for others to follow.

carbon budget

Global emission reduction trajectories associated with a 66% chance of avoiding more than 2°C warming by starting year. Solid black line shows historical emissions, while dashed black line shows emissions constant at 2016 levels. Data and chart design from Robbie Andrew at CICERO and the Global Carbon Project. Illustration: Carbon Brief

Brown’s executive order directs the California Air Resources Board (CARB) to work with relevant state agencies to develop a framework for implementation and accounting of progress toward statewide carbon neutrality. While state agencies can figure out a plan to achieve carbon neutrality, the state legislature will have to pass laws to implement that plan.

California has been all-in on tackling climate change, as its carbon cap and trade system and SB 100 illustrate, but Californians will have to keep electing climate realists to state office in order to make the dream of carbon neutrality a reality.



Kavanaugh’s views on EPA’s climate authority are dangerous and wrong

Posted on 10 September 2018 by dana1981

Donald Trump’s latest Supreme Court nominee Brett Kavanaugh accepts that humans are causing global warming and we need to take action to stop it.  The problem is that he doesn’t trust the experts at EPA to do so and wants to erode their authority to regulate carbon pollution.

Chevron is the key

When discussing Chevron and climate change, we usually focus on the company’s legal liability.  However, in Kavanaugh’s context, ‘Chevron deference’ is even more important.  The term refers to the fact that courts will generally defer to government agency interpretations of laws as long as Congress hasn’t spoken directly to the issue at hand. 

David Doniger, director of the climate and clean air program at the Natural Resources Defense Council noted that Kavanaugh doesn’t believe Chevron deference applies on issues of major importance.  In a recent net neutrality case, Kavanaugh argued, “While the Chevron doctrine allows an agency to rely on statutory ambiguity to issue ordinary rules, the major rules doctrine prevents an agency from relying on statutory ambiguity to issue major rules.”

That’s Kavanaugh’s position on climate change.  In oral arguments before his DC Circuit Court of Appeals in a 2016 Clean Power Plan case, Kavanaugh said:

This is huge case … it has huge economic and political significance … it’s fundamentally transforming an industry by telling existing units you in essence have to pay a penalty, a huge financial penalty in order to continue to exist, in order to shift from coal plants to solar and wind plants, at the same time the coal mining industry is in essence greatly harmed, as well.

But while regulating carbon pollution would have a major impact on the fossil fuel industry, the same is true of most pollutant regulations.  It’s nevertheless EPA’s job to regulate pollutants, and the agency has been doing exactly that since its inception. 



California's response to record wildfires: shift to 100% clean energy

Posted on 3 September 2018 by dana1981

In America today, it’s rare to see political leaders respond to a threat with an appropriate evidence-based policy solution. At the national level, more often we see actions that aggravate existing problems or create new ones. California – the country’s most populous and economically powerful state – has been a welcome exception.

California has been battered by extreme weather intensified by climate change. From 2012 to 2016 the state was scorched by its worst drought in over a millenniumWeather whiplash struck in 2017, when much of the state broke precipitation records. This combination led to devastating mudslides and created the conditions for the most destructive and costly wildfire season on record in 2017, followed by the state’s largest-ever wildfire in 2018, which broke the previous record (set in 2017) by more than 60%.

All of these impacts have been exacerbated by global warming. The past five years have been California’s five hottest on record. And so, the state’s leaders decided to do something about it. California had already set a renewable portfolio standard in 2002, strengthened by Governor Arnold Schwarzenegger’s 2008 executive order requiring that 33% of electricity be generated by renewable sources by 2020. Governor Jerry Brown signed Senate Bill (SB) 350 in 2015, expanding the requirement to 50% renewables by 2030. 

Last week, California state lawmakers passed State Senator (and candidate for US Senate) Kevin de León’s SB 100, which amps up the target to 50% renewables by 2026, 60% by 2030, and 100% from “renewable energy resources and zero-carbon resources” by 2045.

The more aggressive clean energy targets are justified. Not only does California need to make up some of the climate slack created by the Trump administration, but the state is now ahead of its targets, with 29% of electricity last year generated from renewables and over 50% from zero-carbon sources (including nuclear and hydroelectric power).

clean energy

 Percentage of California’s electricity generated by renewables (black) and zero-carbon sources (gray) to date, based California Energy Commission data. The previous renewable target is shown in blue and targets under SB 100 in green. Illustration: Dana Nuccitelli



Trump’s Dirty Power Plan is much worse for kids’ health than for climate change

Posted on 27 August 2018 by dana1981

Last October, then-EPA Administrator Scott Pruitt announced that the agency would repeal the Obama administration’s Clean Power Plan. But because the Supreme Court ruled in 2007 that carbon dioxide is an air pollutant and the Obama EPA correctly concluded that it poses a threat to public welfare via climate change, the EPA is legally obligated to do something to address that threat. That meant they needed a replacement plan.

Last week, the Trump EPA unveiled that plan and inaccurately named it the ‘Affordable Clean Energy Rule.’ The rule basically just extends the life of some dirty coal power plants and encourages them to run a bit more efficiently. The rule’s costs in worsening public health far exceed its monetary benefits. It would more accurately be named the ‘Expensive Dirty Power Plan.’

But there’s a silver lining – coal plants are already shutting down so quicklybecause they can’t compete with cheaper, cleaner alternatives that it turns out we don’t even need the Clean Power Plan to meet Obama’s targets.

Dirty Power Plan’s climate impact is small

Many news stories about the Dirty Power Plan exaggerated its climate impact due to confusion about various points of comparison. For example, the Clean Power Plan aimed to reduce carbon pollution from US electricity generation 32% below 2005 levels by 2030. The Dirty Power Plan will encourage coal plants to operate more efficiently, which the EPA estimates will reduce emissions about 1% more than simply repealing the Clean Power Plan.

That sounds like a big difference between the two plans, and it confused a lot of reporters. The key point is that US electricity generation was already becoming cleaner years before the Clean Power Plan was even conceived. Coal plants have been shutting down so rapidly that power sector carbon pollution is already 25% below 2005 levels. That happened without the Clean Power Plan ever going into effect – we basically didn’t need it, because coal was replaced anyway just for being too expensive.



Sunshine Blogger Award

Posted on 21 August 2018 by BaerbelW

Checking our Twitter stream on July 26, we were pleasantly surprised to notice that Jonathan Dean Coey had nominated Skeptical Science for the Sunshine Blogger Award.


What is the Sunshine Blogger Award?

The award is driven entirely by the community, passed from blogger to blogger in recognition of their inspiring, creative and motivational blogs. Each nominee passes it on to 11 of their favourite bloggers, and round and round it goes. This is a great way to give recognition to bloggers who may otherwise fly under the radar of many people.

For accepting the Sunshine Blogger Award nomination, there are a few rules:

  • Thank the blogger(s) who nominated you and link back to their blog.
  • Answer 11 questions the blogger asked you.
  • Nominate 11 new blogs to receive the award and ask them 11 new questions.
  • List the rules and display the Sunshine Blogger Award in your post and/or on your blog.

So a big thank-you to Jonathan Dean Coey for nominating us for this award! As Skeptical Science is a global team effort, several of us have contributed answers to the questions we received from him. It’s therefore perhaps a bit different compared to other posts in this series where one blog often equals one author!

Jonathan's Questions and Our Answers

1. What will your blog be like in 5 years?

[Baerbel] Hopefully, Skeptical Science (SkS) will no longer need to fight misinformation regarding climate science in 5 years’ time and can actually report on successfully implemented mitigation policies in order to keep global warming to a manageable level (one can dream, right?!?) .

[Dana] We expect that in five years, climate science denial will no longer exist, and Skeptical Science (SkS) will be a nonstop party, celebrating humanity’s evolution to a wiser, more enlightened state that includes finding solutions to the existential threats we face. Of course, that’s also what we thought five years ago!

[David K] I have high confidence that SKS’s list of rebuttals will still be needed five years from now. There are many science deniers who have an amazing ability to avoid reality. And in today’s world of “fake news” their efforts to delay action on climate change will only continue to grow over the next five years.



Trump reignited his war with California, but his Tweet got burned

Posted on 13 August 2018 by dana1981

Last week, 18 wildfires were burning at once in California, including its largest in history, destroying over 1,100 homes and forcing tens of thousands of residents to evacuate. The smoke made the air in the state’s Central Valley unhealthy to breathe for a record 15 consecutive days, as I can personally attest.

Donald Trump decided to use the opportunity to renew his war with California by nonsensically blaming the wildfires on environmental laws.

Donald J. Trump@realDonaldTrump

California wildfires are being magnified & made so much worse by the bad environmental laws which aren’t allowing massive amounts of readily available water to be properly utilized. It is being diverted into the Pacific Ocean. Must also tree clear to stop fire from spreading!

It’s no surprise that Donald Trump dislikes California. His 2.9m national popular vote deficit to Hillary Clinton is a sore spot, and her margin of victory in California was by 30% and 4.3m votes. California has also long been a leader in developing laws to clean and protect the environment, and Trump despises regulations that benefit public health and welfare at the expense of industry profits.

And so, we got the Tweet bemoaning water being “diverted into the Pacific Ocean” (in scientific terms, they’re called “rivers”). Daniel Berlant, assistant deputy director of Cal Fire immediately noted that water isn’t firefighters’ problem:

We have plenty of water to fight these wildfires, but let’s be clear: It’s our changing climate that is leading to more severe and destructive fires



The GOP and Big Oil can't escape blame for climate change

Posted on 6 August 2018 by dana1981

Last week’s issue of the New York Times magazine was devoted to a single story by Nathaniel Rich that explored how close we came to an international climate agreement in 1989, and why we failed. The piece is worth reading – it’s a well-told, mostly accurate, and very informative story about a key decade in climate science and policy history. But sadly, it explicitly excuses the key players responsible for our continued failure.

Culprit #1: The Republican Party

Rich’s piece immediately goes off the rails in its Prologue, where he argues that the GOP isn’t responsible – at least not for the climate failures up to 1989:

Nor can the Republican Party be blamed … during the 1980s, many prominent Republicans joined Democrats in judging the climate problem to be a rare political winner: nonpartisan and of the highest possible stakes.

However, his story is peppered with examples that contradict this narrative. The world’s foremost climate scientists had published the groundbreaking National Academy of Sciences ‘Charney Report’ in 1979, concluding that a doubling of atmospheric carbon dioxide would most likely cause 3°C of global warming (still the consensus today), and as Rich summarizes:



America spends over $20bn per year on fossil fuel subsidies. Abolish them

Posted on 30 July 2018 by dana1981

Imagine that instead of taxing cigarettes, America subsidized the tobacco industry in order to make each pack of smokes cheaper.

report from Oil Change International (OCI) investigated American energy industry subsidies and found that in 2015–2016, the federal government provided $14.7bn per year to the oil, gas, and coal industries, on top of $5.8bn of state-level incentives (globally, the figure is around $500bn). And the report only accounted for production subsides, excluding consumption subsidies (support to consumers to lower the cost of fossil fuel use – another $14.5bn annually) as well as the costs of carbon and other fossil fuel pollutants.

At a time when we need to transition away from fossil fuels as quickly as possible, the federal and state governments are giving the industry tens of billions of dollars to make the production of their dirty, dangerous products more profitable.

We already have to leave tapped fossil fuels in the ground

Crucially, the OCI report noted that if we want to meet the Paris target of limiting global warming to less than 2°C (and we do!), not only does the fossil fuel industry have stop developing new reserves, but “some already-tapped reserves must be retired early.”

carbon budgets

 Developed fossil fuel reserves vs. remaining carbon budget to meet 2°C and 1.5°C Paris climate targets. Illustration: Oil Change International

This reality is incompatible with continued US government subsidization of fossil fuel industry production, including $2.5bn per year for the exploration of new fossil fuel resources ­– new resources that simply cannot be developed if we’re to meet the Paris climate target.



Facebook video spreads climate denial misinformation to 5 million users

Posted on 25 July 2018 by dana1981

Marc Morano is the real-world fossil fuel industry version of Nick NaylorHis career began working for Rush Limbaugh, followed by a job at Cybercast News Service where he launched the ‘Swift Boat’ attacks on 2004 Democratic presidential candidate John Kerry. In 2006, Morano became the director of communications for Senator Jim Inhofe (R-OK), who is perhaps best known for throwing a snowball on the Senate floor and calling human-caused global warming “the greatest hoax ever perpetrated on the American people.”

Thus it’s unsurprising that in 2009, Morano began directing fossil fuel-funded think tanks designed to cast doubt on the reality of and dangers associated with human-caused global warming. As he admitted in Merchants of Doubt, Morano frequently embodies the strategy of climate denial known as ‘fake experts’:

Most recently, Morano created a short video that centers on three common climate myths and has garnered over 5m views on Facebook.



97% of House Republicans foolishly reject carbon taxes

Posted on 20 July 2018 by dana1981

Yesterday, the House of Representatives voted on an anti-carbon tax Resolution. The Resolution was introduced by Steve Scalise (R-LA) with essentially the same language as he introduced in 2013 and 2016.

On those past versions, every Republican House member voted against carbon taxes. This time, six Republicans rejected the Resolution and one abstained, voting ‘Present.’ However, 97% of the House Republicans on the floor voted against carbon taxes.

House Democrats have been fairly consistent in their votes on these Resolutions as well. In 2013, 94% voted against the Resolution, and in 2016 and 2018, 96% voted ‘Nay,’ with six to seven pro-fossil fuel Democrats voting ‘Yes.’

The Resolution is wrong – carbon taxes can be good for the economy

The text of the Resolution claims that carbon taxes are necessarily bad for America:

Expressing the sense of Congress that a carbon tax would be detrimental to the United States economy … [and] to American families and businesses, and is not in the best interest of the United States.

This week’s Resolution ironically came right on the heels of a comprehensive study showing that a carbon tax whose revenues were returned to taxpayers either via rebate checks or by offsetting income taxes would have a negligible impact on the economy – significantly less than the cost of unchecked global warming. In fact, research has shown that it’s global warming that will seriously slow economic growth.

Simply put, the only way to protect the economy is to stop global warming. Accomplishing that will require that virtually every world country implement climate policies aimed at curbing carbon pollution. That was the purpose of the Paris climate accords. Disgracefully, the Trump administration made America the only country in the world whose leadership rejects that international climate agreement. But a carbon tax would be one of the most effective and efficient ways to cut America’s carbon pollution.

The text of the Resolution has it exactly backwards – a carbon tax would help protect the American economy by slowing global warming and its detrimental effects on economic growth.



Comprehensive study: carbon taxes won't hamper the economy

Posted on 16 July 2018 by dana1981

Eleven teams participated in a recent Stanford Energy Modeling Forum (EMF) project, examining the economic and environmental impacts of a carbon tax. The studies included “revenue recycling,” in which the funds generated from a carbon tax are returned to taxpayers either through regular household rebate checks (similar to the Citizens’ Climate Lobby [CCL] and Climate Leadership Council [CLC] proposals) or by offsetting income taxes (similar to the approach in British Columbia).

Among the eleven modeling teams the key findings were consistent. First, a carbon tax is effective at reducing carbon pollution, although the structure of the tax (the price and the rate at which it rises) are important. Second, this type of revenue-neutral carbon tax would have a very modest impact on the economy in terms of gross domestic product (GDP). In all likelihood it would slightly slow economic growth, but by an amount that would be more than offset by the benefits of cutting pollution and slowing global warming.

Meanwhile, House Republicans are again on the verge of introducing a Resolution denouncing a carbon tax as “detrimental to American families and businesses, and is not in the best interest of the United States.”

The strong economic case for a carbon tax

The modeling teams examined four carbon tax scenarios, with starting prices of $25 or $50 per ton of carbon dioxide, rising at 1% or 5% per year. These are somewhat modest policy scenarios; CCL proposes a starting tax of $15 per ton rising at $10 per year, and the CLC proposes $40 per ton rising around 4% per year. The most aggressive policy considered by the Stanford EMF teams ($50 per ton rising 5% per year) falls in between these two proposals.

carbon taxes

 The carbon price each year 2020–2050 in proposals by Citizens’ Climate Lobby (blue), the Climate Leadership Council (red), and the four approaches modeled by the Stanford EMF teams (green). Illustration: Dana Nuccitelli



There are genuine climate alarmists, but they're not in the same league as deniers

Posted on 9 July 2018 by dana1981

Those who debunk climate change misinformation often face a dilemma. We’re flooded with such a constant deluge of climate myths, where should we focus our efforts? Climate misinformation is propagated via congressional climate hearings, conservative media outlets, denial blogs, and even from some genuine climate alarmists. 

Specifically, there has recently been a debate as to whether Skeptical Science– a website with a database of climate myths and scientific debunkings, to which I’m a primary contributor – would be more useful and effective if it called out misinformation from ‘alarmists,’ and if it eliminated or revised its Climate Misinformers page.

Richard Betts@richardabetts

I describe the SkS lists as political because their 'misinformer' lists don't include those on the 'climate action' side who actively deny science & espouse conspiracy ideation

There is some validity to these critiques, and in response, Skeptical Science is renaming the page ‘Climate misinformation by source.’ But the site is run entirely by a team of international volunteers, and as such, opportunity costs must be considered. Time devoted to refuting alarmists is time not devoted to debunking the constant deluge of climate denial.



Republicans try to save their deteriorating party with another push for a carbon tax

Posted on 2 July 2018 by dana1981

The Republican Party is rotting away
. The problem is that GOP policies just aren’t popular. Most Americans unsurprisingly oppose climate denial, tax cuts for the wealthy, and putting children (including toddlers) in concentration camps, for example.

The Republican Party has thus far managed to continue winning elections by creating “a coalition between racists and plutocrats,” as Paul Krugman put it. The party’s economic policies are aimed at benefitting wealthy individuals and corporations, but that’s a slim segment of the American electorate. The plutocrats can fund political campaigns, but to capture enough votes to win elections, the GOP has resorted to identity politics. Research has consistently shown that Trump won because of racial resentment among white voters.

While that strategy has worked in the short-term, some Republicans recognize that it can’t work in the long-term, and they’re fighting to save their party from extinction.

Can a carbon tax save the GOP?

Climate change is one of many issues that divides the Republican Party. Like racial resentment, climate denial is a position held mostly by old, white, male conservatives. There’s a climate change generational, ethnic, and gender gap. 61% of Republicans under the age of 50 support government climate policies, compared to just 44% of Republicans over 50. Similarly, a majority of Hispanic- and African-Americans accept human-caused global warming and 70% express concern about it, as compared to just 41% of whites who accept the scientific reality and 50% who worry about it.

But the plutocratic wing of the GOP loves fossil fuels. Republican politicians rely on campaign donations from the fossil fuel industry, and quid pro quo requires them to do the industry’s bidding. It might as well be called the Grand Oil Party.



30 years later, deniers are still lying about Hansen’s amazing global warming prediction

Posted on 25 June 2018 by dana1981

30 years ago, James Hansen testified to Congress about the dangers of human-caused climate change. In his testimony, Hansen showed the results of his 1988 study using a climate model to project future global warming under three possible scenarios, ranging from ‘business as usual’ heavy pollution in his Scenario A to ‘draconian emissions cuts’ in Scenario C, with a moderate Scenario B in between.

Changes in the human effects that influence Earth’s global energy imbalance (a.k.a. ‘anthropogenic radiative forcings’) have in reality been closest to Hansen’s Scenario B, but about 20–30% weaker thanks to the success of the Montreal Protocol in phasing out chlorofluorocarbons (CFCs). Hansen’s climate model projected that under Scenario B, global surface air temperatures would warm about 0.84°C between 1988 and 2017. But with a global energy imbalance 20–30% lower, it would have predicted a global surface warming closer to 0.6–0.7°C by this year.

The actual 1988–2017 temperature increase was about 0.6°C. Hansen’s 1988 global climate model was almost spot-on.

Hansen 88

Scenario B from Hansen’s 1988 paper, with the trend reduced by 27% to reflect the actual radiative forcing from 1984 to 2017, compared to global surface temperature data from Cowtan & Way. Illustration: Dana Nuccitelli



Should we be worried about surging Antarctic ice melt and sea level rise?

Posted on 18 June 2018 by dana1981

There’s recently been a spate of sea level rise denial in the conservative media, but in reality, sea level rise is accelerating and melting ice is playing an increasingly large role. In the first half of the 20th Century, average global sea level rose by about 1.4 millimeters per year (mm/yr). Since 1993, that rate has more than doubled to 3.2 mm/yr. And since 2012, it’s jumped to 4.5 mm/yr.


Global mean sea level data from the Colorado University Sea Level Research Group, with 4-to-5-year linear trends shown in black and red. Illustration: Dana Nuccitelli

Thermal expansion (ocean water expanding as it warms) continues to play the biggest role in sea level rise, but its contribution of about 1.3 mm/yr is now responsible for a smaller proportion of total sea level rise (30% in recent years) than its contribution since the 1990s (40% of the total). That’s because of the acceleration in melting ice.

Glacier melt is accelerating, recently contributing about 0.75 mm/yr to sea level rise, up from 0.65 mm/yr since the 1990s. But the biggest jumps have come from ice in Greenland and Antarctica. Greenland had been responsible for about 0.48 mm/yr sea level rise since 1990, but in recent years is up to 0.78 mm/yr. A recent study in Nature Climate Change found that Greenland contributed about 5% to sea level rise in 1993 and 25% in 2014.



Benefits of curbing climate change far outweigh costs

Posted on 12 June 2018 by dana1981

Those who oppose policies to cut carbon pollution and slow climate change always claim that doing so will be too expensive and cripple the economy. They argue that instead we should maximize economic growth so that we can pay for climate damages and adaptation in the future. It’s an argument helped by the fact that models have essentially treated economic growth as an external factor that won’t be significantly impacted by climate change.

That assumption has been challenged in recent years, starting with a 2012 paper in theAmerican Economic Journal finding that higher temperatures reduce economic growth rates, particularly in poorer countries. A 2015 paper by Stanford scientists published inNature Climate Change built on this work, similarly finding that global warming will particularly hurt economic growth in poorer countries, and that “Optimal climate policy in this model stabilizes global temperature change below 2 degrees C.” This finding is consistent with the target set by the Paris climate accords. 

Later in 2015, a team of scientists led by Marshall Burke published a paper inNature finding a relationship between temperature and Gross Domestic Product, or GDP. There’s a sweet spot where regions with an average temperature around 13 degrees Celsius (55 degrees Fahrenheit) have the highest economic productivity. When temperatures are much hotter or colder, GDP falls. Countries like the United States, Japan, China, and many European countries happen to have temperatures right near that sweet spot, while many developing countries closer to the equator—in regions like Africa and southeast Asia—are already hotter than optimal. Consistent with the findings of the aforementioned studies, the economies of these poorer tropical countries will be particularly hard hit by global warming, because their climates are already sub-optimally hot.

Just recently, Burke led another team of scientists in research quantifying these economic costs of higher temperatures. Their latest paper, also published in Nature, found that limiting global warming to 1.5 degrees Celsius would likely save the global economy more than $20 trillion by the year 2100 as compared to 2 degrees Celsius warming—at a cost of about $300 billion. That means the benefits of curbing climate change would exceed the costs by about 70-to-1. The study also only accounts for temperature effects on GDP and not other damaging factors like sea level rise, and is thus likely a conservative estimate.



The Wall Street Journal keeps peddling Big Oil propaganda

Posted on 11 June 2018 by dana1981

The Wall Street Journal (WSJ) Opinion page has long had a conservative skew, and unfortunately that has extended to politicizing climate change with biased and factually inaccurate editorials.

Over the past several weeks, the WSJ’s attacks on climate science have gone into overdrive. On May 15th, the Opinion page published a self-contradictory editorial from the lifelong contrarian and fossil fuel-funded Fred Singer that so badly rejected basic physics, it prompted one researcher to remark, “If this were an essay in one of my undergraduate classes, he would fail.”

The WSJ did publish a letter to the editor (LTE) from real climate scientistsAndrea Dutton and Michael Mann rebutting Singer’s editorial. However, it gave the last word to science deniers in an LTE response rejecting the well-established facts that sea level rise is accelerating and Antarctic is loss is contributing to it.

A few days later, the WSJ opinion page was at it again, publishing an editorialby Stephen F. Hayward, who describes himself as having “spent most of my adult life in conservative think tanks in Washington, D.C.,” and it shows. Hayward has a long history as a climate naysayer, spanning over a decadeback to his days with the fossil fuel-funded American Enterprise Institute.

Playing Whack-a-Mole with Hayward’s Gish Gallop

Hayward’s arguments of course deserve to be judged on their own merits. I devoted my first-ever Tweetstorm to doing just that:

Dana Nuccitelli@dana1981

Ok, let's do a Whack-a-Mole Twitter thread debunking all the nonsense in @stevenfhayward's @WSJ editorial (1/n)



The latest weak attacks on EVs and solar panels

Posted on 4 June 2018 by dana1981

Over the past two weeks, media attacks on solar panels and electric vehicles have been followed by Trump administration policies aimed at boosting their fossil fueled rivals.

Efforts to undermine solar power

The first salvo came via a Forbes article written by Michael Shellenberger, who’s running a doomed campaign for California governor and really loves nuclear power. Shellenberger’s critique focused on the problem of potential waste at the end of a solar panel lifespan when the modules must be disposed or recycled. It’s a somewhat ironic concern from a proponent of nuclear power, which has a rather bigger toxic waste problem.

About 80% of a solar panel module can be recycled, but some portions cannot, and create potentially hazardous waste due to the presence of metals like cadmium and lead. The Electric Power Research Institute notes that long-term storage of used panels until recycling technologies become available may be the best option for dealing with this waste stream. Ultimately, it’s an issue that will need to be addressed as solar panels become more widespread and reach the end of their 25-plus year lifespan, much like the issue of nuclear waste. But it’s an issue that we should be able to resolve with smart policies and technologies.

It’s also not a big near-term concern, unlike the urgent need to deploy low-carbon energy, or an immediate pollution problem like for example the environmental crises that result when oil rigs fail or coal barges sink into rivers.

Shellenberger also raised concerns about the possibility “that cadmium can be washed out of solar modules by rainwater.” But that’s only a problem for broken panels, which are relatively rare except perhaps in the wake a natural disaster like a hurricane or earthquake. In a disaster area, leaching of metals from some broken solar panels is the least of a city’s problems.



Trump administration refuses to consider that 97% of climate scientists could be right

Posted on 29 May 2018 by dana1981

Last week, the Washington Post obtained a White House internal memo that debated how the Trump administration should handle federal climate science reports.

The memo presented three options without endorsing any of them: conducting a “red team/blue team” exercise to “highlight uncertainties in climate science”; more formally reviewing the science under the Administrative Procedure Act; or deciding to just “ignore, and not seek to characterize or question, the science being conducted by Federal agencies and outside entities.”

In short, the White House considered ‘debating’ established climate science, casting doubt on scientists’ conclusions, or just ignoring them. Accepting and/or acting on the findings of the scientific experts is not an option they’re willing to consider.

Katharine Hayhoe@KHayhoe

So according to this memo, the administration considered 3 options--(1) framing reality as being up for debate; (2) developing their own view of reality; or (3) ignoring reality--and went with option 3.

Interesting that "accepting reality" was not an option. 



Yes, EVs are green and global warming is raising sea levels

Posted on 21 May 2018 by dana1981

Last week, the House Science, Space and Technology Committee held yet another climate science hearing similar to those from April 2017February 2017January 2016May 2015June 2014December 2013, and so on. It seems as though disputing established climate science is House Republicans’ favorite hobby. This time, it was Philip Duffy’s turn to spend two hours playing whack-a-mole with the committee Republicans’ endless supply of long-debunked climate myths.

Rep. Mo Brooks (R-AL) claimed that sea level rise is due to the White Cliffs of Dover tumbling into the ocean (yes, really), and his colleagues argued that scientists in the 1970s were predicting global cooling, that Earth is just returning to its “normal temperature,” that Antarctic ice is growing, and sea levels are hardly rising.

Self-contradictory sea level rise denial

Those last two claims originated from a Wall Street Journal (WSJ) editorialentered into the Congressional record by Chairman Lamar Smith (R-TX), written by Fred Singer. As the group Ozone Action documented, Singer has been a lifetime contrarian on virtually every scientific subject imaginable - acid rain, nuclear winter, nuclear waste, nuclear war, ozone depletion, secondhand smoke, amphibian population loss, and even minimum wage benefits. In recent decades he’s worked for a plethora of fossil fuel-funded think tanks, denying established climate science.

Singer’s WSJ editorial is difficult to follow, largely because it contradicts itself several times, saying:



California, battered by global warming’s weather whiplash, is fighting to stop it

Posted on 14 May 2018 by dana1981

In 1988 – the same year Nasa’s James Hansen warned Congress about the threats posed by human-caused global warming – water expert Peter Gleick wrote about the wet and dry extremes that it would create for California:

California will get the worst of all possible worlds – more flooding in the winter, less available water in the summer.

Three decades later, California has been ravaged by just this sort of weather whiplash. The state experienced its worst drought in over a millennium from 2012 to 2016, followed immediately by its wettest year on record in 2017. The consequences have been similarly extreme, including hellish record wildfiresnarrowly-avoided catastrophic flooding at Oroville Dam, and deadly mudslides.

A study published last month in Nature Climate Change found that these wet and dry extremes will only worsen in California as temperatures continue to rise. As lead author Daniel Swain wrote:

most of California will likely experience a 100 – 200% increase in the frequency of very wet November-March “rainy seasons” … California will likely experience an increase of anywhere from 50% to 150% (highest in the south) in the frequency of very dry November-March periods … Since California is so dependent on precipitation during its relatively brief winter rainy season, even a single dry winter can quickly lead to adverse drought impacts upon agriculture and the environment.

Swain fig

Relative change (in percent) in extremely wet seasons and extremely dry seasons by 2070-2100 in Southern California. Illustration: Swain et al. 2018, Nature Climate Change



Global warming will depress economic growth in Trump country

Posted on 7 May 2018 by dana1981

A working paper recently published by the Federal Reserve Bank of Richmond concludes that global warming could significantly slow economic growth in the US.

Specifically, rising summertime temperatures in the hottest states will curb economic growth. And the states with the hottest summertime temperatures are all located in the South: Florida, Louisiana, Texas, Mississippi, Oklahoma, Alabama, Georgia, South Carolina, Arkansas, and Arizona. All of these states voted for Donald Trump in 2016.

This paper is consistent with a 2015 Nature study that found an optimal temperature range for economic activity. Economies thrive in regions with an average temperature of around 14°C (57°F). Developed countries like the US, Japan, and much of Europe happen to be near that ideal temperature, but continued global warming will shift their climates away from the sweet spot and slow economic growth. The question is, by how much?

The new working paper concludes that if we meet the Paris target of staying below 2°C global warming, US economic growth will only slow by about 5 to 10%. On our current path, including climate policies implemented to date (which would lead to 3–3.5°C global warming by 2100), US economic growth would slow by about 10 to 20%. In a higher carbon pollution scenario (4°C global warming by 2100), US economic growth would slow by about 12 to 25% due to hotter temperatures alone.

Republicans have this totally wrong

House Majority Whip Steve Scalise, who represents Louisiana (the second-hottest state), recently introduced a new anti-carbon tax House Resolution. Scalise introduced similar Resolutions in 2013 with 155 co-sponsors (154 Republicans and 1 Democrat) and in 2015 with 82 co-sponsors (all Republicans). The latest version currently only has one co-sponsor, but more will undoubtedly sign on. All three versions of the Resolution include text claiming, “a carbon tax will lead to less economic growth.”

As the economics research shows, failing to curb global warming will certainly lead to less economic growth. Climate policies could hamper economic growth, but legislation can be crafted to address that concern.

For example, as Citizens’ Climate Lobby notes in its point-by-point response to the Scalise Resolution, an economic analysis of the group’s proposed revenue-neutral carbon tax policy found that it would modestly spur economic growth(increasing national GDP by $80 to 90bn per year). With this particular policy, 100% of the carbon tax revenue is returned equally to households, and for a majority of Americans, this more than offsets their increased costs. As a result, real disposable income rises, and Americans spend that money, spurring economic growth.


Modeled change in real disposable personal income in the US resulting from the CCL rising revenue-neutral carbon tax. Illustration: Regional Economic Models, Inc.



Republicans have so corrupted EPA, Americans can only save it in the voting booth

Posted on 30 April 2018 by dana1981

Like Donald Trump and the rest of his administration, Scott Pruitt has been caught up in so many scandals that it becomes impossible to focus on any single act of corruption. It’s difficult to focus on the damage Pruitt is doing to the environment and public health when seemingly every day there’s a new scandal related to his illegal $43,000 phone booth, or use of Safe Water Drinking Act funds to give two staffers a total of $85,000 in raises (and lying about it), or his sweetheart deal on a condo rental from a lobbyist’s wife (and lying about having met with that lobbyist), or wasting taxpayer funds on first class air travel and military jets, and a nearly $3m per year security detail, and bulletproof car seat covers, and a bulletproof desk, and so on.

Lisa Friedman@LFFriedman

Number of federal investigations into Scott Pruitt has now risen to 11. Reps. Beyer & Lieu say EPA inspector general will take up an inquiry into the $50-a-night condo rental from the wife of an energy lobbyist.

But while Pruitt’s unprecedented corruption is staggering and would have resulted in his firing long ago in any other presidential administration, the damage Pruitt is doing to public and environmental health is a far greater scandal yet. As George W. Bush’s former EPA administrator Christine Todd Whitman wrote in the scathing explanation for why TIME included Pruitt as one of its 100 most influential people this year,

If his actions continue in the same direction, during Pruitt’s term at the EPA the environment will be threatened instead of protected, and human health endangered instead of preserved, all with no long-term benefit to the economy.



Pruitt promised polluters EPA will value their profits over American lives

Posted on 23 April 2018 by dana1981

TIME magazine announced last week that Trump’s EPA administrator Scott Pruitt is among their 100 most influential people of 2018. George W. Bush’s former EPA administrator Christine Todd Whitman delivered the scathing explanation:

If his actions continue in the same direction, during Pruitt’s term at the EPA the environment will be threatened instead of protected, and human health endangered instead of preserved, all with no long-term benefit to the economy.

As a perfect example of those actions, the Daily Caller recently reported that at a gathering at the fossil fuel-funded Heritage Institute, Pruitt announced that the EPA and federal government will soon end two important science-based practices in evaluating the costs and benefits of regulations.

Regulating pollutants has “co-benefits,” like saving lives

When the EPA regulates pollutants, the practice often yields what are called “co-benefits.” For example, limiting allowable mercury pollution can force dirty coal power plants to install pollution-control equipment or shut down. Since coal plants produce other pollutants like soot, the regulations not only reduce mercury levels, but also particulate matter in the air. The latter isn’t an intended consequence of the regulations, but creating cleaner air and healthier Americans are unintended “co-benefits” of limiting another pollutant.

In doing cost-benefit analyses, the EPA accounts for all direct benefits and indirect co-benefits of its regulations. Certain industry groups and conservative pundits don’t like that approach, because they care more about polluter profits than they do about clean air and healthy Americans. However, during the George W. Bush administration in 2003, the Office of Management and Budget issued a guidance saying that it’s important to consider co-benefits:



The courts are deciding who's to blame for climate change

Posted on 16 April 2018 by dana1981

There are numerous ongoing legal challenges in an effort to determine who’s responsible for climate change. Exxon is under investigation by state attorneys general, cities are suing oil companies over sea level rise costs, and Our Children’s Trust is suing the federal government for failing to protect their generation from climate change. At the heart of these legal challenges lies the question – who bears culpability for climate change and liability for its costs and consequences?

Like Exxon, Shell Knew

Exxon has been a prime target of these investigations and lawsuits since Inside Climate News’ investigative journalism revealed that the company’s internal climate science research warned of the dangers posed by human-caused global warming since the late 1970s.

Recently, Dutch journalist Jelmer Mommers of De Correspondent unearthed internal documents from Shell that began warning of the dangers associated with human-caused climate change 30 years ago. The company’s 1988 report titled “The Greenhouse Effect” warned,

by the time the global warming becomes detectable it could be too late to take effective countermeasures to reduce the effects or even stabilise the situation.

And, particularly relevant to Our Children’s Trust’s lawsuits, Shell’s 1988 report warned of the climate consequences for future generations.


Similarly, in a 1991 film called Climate of Concern, Shell warned,



EPA’s war with California proves America needs a carbon tax

Posted on 10 April 2018 by dana1981

Last week, Trump’s EPA announced that it will repeal the vehicle fuel efficiency standards set under the Obama administration and replace them with weaker requirements. EPA also threatened to revoke California’s ability under the Clean Air Act to impose its own greenhouse gas standards. If they do so, California’s attorney general will sue the EPA.

Xavier Becerra@AGBecerra

The Trump Administration’s assault on clean car standards risks our ability to protect our children’s health, tackle climate change, and save hardworking Americans money. We’re ready to file suit if needed to protect these critical standards: 

This lawsuit would be tied up in court for years, and in the meantime California’s more stringent standards would remain in place. Those standards have been adopted by 12 other states, which along with California account for one-third of new car sales in America. Weaker federal fuel efficiency standards wouldn’t much help the US auto industry if they don’t apply to one-third of domestic sales.

The Obama administration set the stricter fuel efficiency standards after the federal government was forced to bail out the auto industry. Struck by the 2008 global recession and a spike in fuel prices, US auto manufacturers, whose fleets were less fuel efficient than foreign competitors, were in dire financial straits. The auto industry thus accepted the federal bailout and didn’t fight the higher fuel efficiency standards – until Donald Trump came into office. California also agreed to the new federal standards in 2008, and now wants to use its Clean Air Act authorization to keep them.

The auto industry has argued that low gasoline prices are the problem, but that’s not a problem they want to solve. In fact, US automakers are in the process of repeating the same mistakes that led to the industry collapse a decade ago:



American conservatives are still clueless about the 97% expert climate consensus

Posted on 5 April 2018 by dana1981

Gallup released its annual survey on American perceptions about global warming last week, and the results were a bit discouraging. While 85–90% of Democrats are worried about global warming, realize humans are causing it, and are aware that most scientists agree on this, independents and Republicans are a different story. Only 35% of Republicans and 62% of independents realize humans are causing global warming (down from 40% and 70% last year, respectively), a similar number are worried about it, and only 42% of Republicans and 65% of independents are aware of the scientific consensus – also significantly down from last year’s Gallup poll.

The Trump administration’s polarizing stance on climate change is probably the main contributor to this decline in conservative acceptance of climate change realities. A recent study found evidence that “Americans may have formed their attitudes [on climate change] by using party elite cues” delivered via the media. In particular, the study found that Fox News “is consistently more partisan than other [news] outlets” and has incorporated politicians into the majority of its climate segments.

Americans are gradually becoming better-informed

Nevertheless, public awareness about climate change realities has improved over the long-term. For example, about two-thirds of Americans now realize that most scientists agree global warming is occurring, up from less than half in 1997.

gallup 1

Responses to Gallup survey question asking whether most scientists believe global warming is occurring. Illustration: Dana Nuccitelli



Climate scientists debate a flaw in the Paris climate agreement

Posted on 29 March 2018 by dana1981

In September 2017, a team led by the University of Exeter’s Richard Millar published a paper in Nature Geoscience, which was widely reported as suggesting that the Paris climate agreement’s aspirational goal of limiting global warming to 1.5°C above pre-industrial temperatures is still technically within our reach. Many other climate scientists were skeptical of this result, and the journal recently published a critique from a team led by the University of Edinburgh’s Andrew Schurer.

The debate lies in exactly how the Paris climate target is defined and measured, which has not been precisely established. Millar’s team used the UK Met Office and Hadley Centre global surface temperature dataset called HadCRUT4, which begins in 1850 and estimates global surface temperatures have warmed about 0.9°C since that time. The team thus calculated the remaining carbon budget that will lead to an additional 0.6°C warming.

The three issues underlying the vague Paris target

But HadCRUT4 has some significant flaws. First, it only covers 84% of Earth’s surface. There are large gaps in its coverage, mainly in the Arctic, Antarctica, and Africa, where temperature monitoring stations are relatively scarce. And the Arctic is the fastest-warming part of the planet, which means that HadCRUT4 somewhat underestimates global warming.

Coverage bias in the HadCRUT4 temperature series and its impact on recent temperature trends, by Kevin Cowtan.



In court, Big Oil rejected climate denial

Posted on 27 March 2018 by dana1981

In a California court case this week, Judge William Alsup asked the two sides to provide him a climate science tutorial.

The plaintiffs are the coastal cities of San Francisco and Oakland. They’re suing five major oil companies (Chevron, ExxonMobil, Shell, ConocoPhillips and BP) to pay for the cities’ costs to cope with the sea level rise caused by global warming. Chevron’s lawyer presented the science for the defense, and most notably, began by explicitly accepting the expert consensus on human-caused global warming, saying:

From Chevron’s perspective, there is no debate about the science of climate change

Deniers still want to debate the science of climate change

Deniers filed briefs in support of the defense, but they contradicted Chevron’s tutorial. For example, one brief filed by a group led by Christopher Monckton and Willie Soon began by stating, “The “consensus” about global warming is 0.3%, not 97%” (this is obviously incorrect). Another brief filed by William HapperSteve Koonin, and Richard Lindzen argued that “It is not possible to tell how much of the modest recent warming can be ascribed to human influences.” Chevron and the IPCC disagree.



Developing countries need fossil fuels to reach the standard of living we enjoy, right?

Posted on 20 March 2018 by dana1981



John Kelly shut down Pruitt’s climate denial ‘red team,’ but they have a Plan B

Posted on 19 March 2018 by dana1981

In 2007, the US Supreme Court ruled that carbon dioxide is an air pollutant, which means that if it poses a threat to public health or welfare, the EPA must regulate it under the Clean Air Act. In 2009, the EPA completed its review of the climate science literature and correctly concluded in its Endangerment Findingthat carbon pollution poses such a threat via climate change. That document is the foundation for all government climate policies, including the Obama Administration’s Clean Power Plan. Climate deniers have thus long had their sights set on revoking the Endangerment Finding.

That’s a tall order, since the scientific literature is crystal clear on this question. House Republicans first tried to simply rewrite the Clean Air Act to state the greenhouse gases aren’t pollutants, but they failed to get nearly enough support to pass that legislation. Next they proposed setting up a ‘Red Team’ of climate deniers to debate the mainstream climate science ‘Blue Team.’ But Trump’s chief of staff John Kelly worried that having this prominent debate on the record would be a distraction and potentially expose the administration to litigation, so he killed the idea

However, E&E News reports that Pruitt has a safer Plan B: take public comments on petitions asking EPA to revisit the Endangerment Finding. This would appease the deniers by allowing them to officially make their case, but the EPA wouldn’t be under any obligation to take action. It’s a fight Pruitt knows he would lose in court, because the science is not on the deniers’ side, so he would prefer to simply weaken the Clean Power Plan, eliminate as many other federal climate policies as possible, and delay all US climate action until the clock runs out on the Trump administration.



Burning coal may have caused Earth’s worst mass extinction

Posted on 12 March 2018 by dana1981

Earth has so far gone through five mass extinction events – scientists are worried we’re on course to trigger a sixth – and the deadliest one happened 252 million years ago at the end of the Permian geologic period. In this event, coined “the Great Dying,” over 90% of marine species and 70% of terrestrial vertebrate species went extinct. It took about 10 million years for life on Earth to recover from this catastrophic event.

Scientists have proposed a number of possible culprits responsible for this mass extinction, including an asteroid impact, mercury poisoning, a collapse of the ozone layer, and acid rain. Heavy volcanic activity in Siberia was suspected to play a key role in the end-Permian event.

Recently, geologist Dr Benjamin Burger identified a rock layer in Utah that he believed might have formed during the Permian and subsequent Triassic period that could shed light on the cause of the Great Dying.


Sheep Creek Valley, Utah. Photograph: Benjamin Burger

During the Permian, Earth’s continents were still combined as one Pangea, and modern day Utah was on the supercontinent’s west coast. Samples from the end-Permian have been collected from rock layers in Asia, near the volcanic eruptions, but Utah was on the other side of Pangaea. Burger’s samples could thus provide a unique perspective of what was happening on the other side of the world from the eruptions. Burger collected and analyzed samples from the rock layer, and documented the whole process in a fascinating video:



Stop blaming ‘both sides’ for America’s climate failures

Posted on 5 March 2018 by dana1981

Steven Pinker is a cognitive psychologist, linguist, and author of Bill Gates’ two favorite books. However, his latest – Enlightenment Now – has some serious shortcomings centering on Pinker’s misperceptions about climate change polarization. Pinker falls into the trap of ‘Both Siderism,’ acknowledging the Republican Party’s science denial, but also wrongly blaming liberals for the policy stalemate, telling Ezra Klein:

there is implacable opposition to nuclear energy in much of the environmental movement ... There are organizations like Greenpeace and NRDC who are just dead set opposed to nuclear. There are also people on the left like Naomi Klein who are dead set against carbon pricing because it doesn’t punish the polluters enough ... the people that you identify who believe in a) carbon pricing and b) expansion of nuclear power, I suspect they’re a tiny minority of the people concerned with climate … What we need are polling data on how many people really would support carbon pricing and an expansion of nuclear and other low carbon energy sources.

Here Pinker has created a strange straw man that bears no resemblance to the real population of American liberals and environmentalists. In fact, the polling data he wonders about already exists.

For example, a 2016 survey by Yale and George Mason universities found that 73% of Democrats support a carbon tax or a combination of tax and regulations (a further 17% favored carbon pollution regulations only). In fact, most consider putting a price on carbon pollution the single most crucial step in tackling global warming. Even Naomi Klein has said, “I don’t think a carbon tax is a silver bullet, but I think a progressively designed carbon tax is part of a slate of policies that we need.”

While it’s true that a majority of liberals oppose building more nuclear power plants, 38% support the idea. Some environmental groups like Greenpeace do oppose nuclear power, but Pinker’s other example, NRDC merely points out that new nuclear plants are currently uneconomical, and even suggests, “The federal government should continue to fund research into nuclear energy.” There are strong economic reasons to oppose building new nuclear power as an inefficient use of resources when renewables today are cheaper and can be deployed more quickly. That being said, were nuclear power funding included in comprehensive legislation to tackle climate change, most liberals and environmentalists would accept that deal in a heartbeat.



Actions today will decide Antarctic ice sheet loss and sea level rise

Posted on 1 March 2018 by dana1981

A new study published in Nature looks at how much global sea level will continue to rise even if we manage to meet the Paris climate target of staying below 2°C hotter than pre-industrial temperatures. The issue is that sea levels keep rising for several hundred years after we stabilize temperatures, largely due to the continued melting of ice sheets in Antarctica and Greenland from the heat already in the climate system.

The study considered two scenarios. In the first, human carbon pollution peaks somewhere between 2020 and 2035 and falls quickly thereafter, reaching zero between 2035 and 2055 and staying there. Global temperatures in the first scenario peak at and remain steady below 2°C. In the second scenario, we capture and sequester carbon to reach net negative emissions (more captured than emitted) between 2040 and 2060, resulting in falling global temperatures in the second half of the century.

The authors found that global average sea level will most likely rise by about 1.3 meters by 2300 in the first scenario, and by 1 meter in the second. However, there is large uncertainty due to how little we understand about the stability of the large ice sheets in Greenland and especially Antarctica. At the high end of possible ice sheet loss, we could see as much as 4.5 meters of sea level rise by 2300 in the first scenario, and close to 3 meters in the second scenario.

fig 1

Carbon emissions (top frames), global temperatures (middle frames), and sea level rise (left frames) in the study’s two scenarios (left and right frames). Illustration: Mengel et al. (2018), Nature Communications



What role did climate change play in this winter’s US freezes, heat, and drought?

Posted on 28 February 2018 by dana1981

This is a re-post from the Citizens' Climate Lobby Blog by Dana Nuccitelli and Doug Sinton, CCL Science Policy Network Team

There is growing scientific evidence suggesting that human-caused global warming is causing rapid changes in the Arctic, which in turn is altering the atmosphere, causing wavy patterns to form more frequently in the jet stream. On the West Coast, this can cause persistent high-pressure systems to form in the Pacific, exacerbating droughts by blocking storm systems. It can also allow frigid Arctic air to spill into the USA, creating especially cold winter weather. In sum, these freezes, heat, and droughts are made more likely by rising global temperatures, and as they rise further, such extremes may well become more common.

Abnormal winter weather

This winter, the eastern USA was hit by frigid cold weather, although at the same time, the western states (and most of the rest of the world) were relatively toasty:

Surface temperatures, Arctic, North America, NASA

North American surface temperatures for Dec. 26, 2017 – Jan. 2, 2018, from NASA Earth Observatory

This prompted a presidential tweet suggesting, “Perhaps we could use a little bit of that good old Global Warming.” It’s a natural reaction, when in the midst of frigid weather, to wonder how such cold conditions can strike in a world that’s being heated by global warming. However, scientific research has suggested that, counterintuitively, climate change appears to be playing a role in making these cold winter weather events happen more often in some regions.



News network climate reporting soared in 2017 thanks to Trump

Posted on 15 February 2018 by dana1981

In 2016, US TV network news coverage of climate change plummeted. News coverage was focused on the presidential election, but the corporate broadcast networks didn’t air a single segment informing viewers how a win by Trump or Hillary Clinton could affect climate change or climate policy. That followed a slight drop in news coverage of climate change in 2015, despite that year being full of critical events like the Paris climate accordsClean Power Plan, and record-breaking heat.

The good news is that the annual analysis done by Media Matters for America found that in 2017, network news coverage of climate change soared.


Minutes of US corporate news network climate coverage by year, 2014–2017. Data from Media Matters for America. Illustration: Dana Nuccitelli



The EPA debunked Administrator Pruitt’s latest climate misinformation

Posted on 12 February 2018 by dana1981

Last week, a Las Vegas news station interviewed Trump’s EPA administrator Scott Pruitt. The interviewer brought up the topic of climate change, and virtually everything Pruitt said in response was wrong, and was often refuted on his own agency’s website, until he started deleting it.

Humans are causing global warming. All of it.

To begin, Pruitt claimed that we don’t know ‘with precision’ what’s causing global warming.

Our activity contributes to the climate changing to a certain degree. Now measuring that with precision, Gerard, I think is more challenging than is let on at times.

Here’s what the EPA website said about that a year ago, before Pruitt got a hold of it as part of the Trump Administration’s systematic deletion of government climate change websites:

Research indicates that natural causes do not explain most observed warming, especially warming since the mid-20th century. Rather, it is extremely likely that human activities have been the dominant cause of that warming.

To support this statement, the EPA referenced the latest IPCC report. The IPCC concluded with 95% confidence that humans are the main cause of global warming since 1950, with a best estimate that humans are responsible for all of the global warming during that time. That’s what the scientific research has overwhelmingly concluded:

all of it

The percentage of human contribution to global warming over the past 50-65 years from various peer-reviewed studies. Illustration: Dana Nuccitelli and John Cook



Humans need to become smarter thinkers to beat climate denial

Posted on 6 February 2018 by dana1981

Climate myths are often contradictory – it’s not warming, though it’s warming because of the sun, and really it’s all just an ocean cycle – but they all seem to share one thing in common: logical fallacies and reasoning errors.

John Cook, Peter Ellerton, and David Kinkead have just published a paper in Environmental Research Letters in which they examined 42 common climate myths and found that every single one demonstrates fallacious reasoning. For example, the authors made a video breaking down the logical flaws in the myth ‘climate changed naturally in the past so current climate change is natural.’

Video abstract for paper “Deconstructing climate misinformation to identify reasoning errors” published in Environmental Research Letters by John Cook, Peter Ellerton, and David Kinkead.

Beating myths with critical thinking

Cook has previously published research on using ‘misconception-based learning’to dislodge climate myths from peoples’ brains and replace them with facts, and beating denial by inoculating people against misinformers’ tricks. The idea is that when people are faced with a myth and a competing fact, the fact will more easily win out if the fallacy underpinning the myth is revealed. In fact, these concepts of misconception-based learning and inoculation against myths were the basis of the free online Denial101x course developed by Cook and colleagues.



It's not okay how clueless Donald Trump is about climate change

Posted on 1 February 2018 by dana1981

Donald Trump has decimated all presidential norms to such a degree that it’s now difficult to feel alarmed or outraged when he inevitably breaks another. It was difficult to raise an eyebrow when the story broke that Trump paid off a porn star to remain silent about their affair, which happened just after his third wife had given birth to his fifth child, because it’s Donald Trump – of course he did.

Likewise, when Trump made a number of grossly ignorant and wrong commentsabout climate change in an interview with Piers Morgan last week, my first reaction was ‘it’s Donald Trump – of course he did.’

But that’s not okay. Donald Trump is the leader of the country most culpable for the existential threat that we’ve created by rapidly changing Earth’s climate. His administration is alone in the world in declaring that we need not worry about that existential threat. We need to hold him to account for his ignorance on this critically important issue and demand better.

Trump’s ignorant climate comments

Trump’s climate comments in the interview were so ridiculously misinformed that even late night comedians were able to debunk them:

They’re claims you might expect from a YouTube troll, not the leader of the country that produces some of the best climate science research and data in the world. It would be easy to laugh them off as Trump’s usual buffoonery, but he should be held to a presidential standard. So, to briefly debunk each of these myths:



Natural gas killed coal – now renewables and batteries are taking over

Posted on 29 January 2018 by dana1981

Over the past decade, coal has been increasingly replaced by cheaper, cleaner energy sources. US coal power production has dropped by 44% (866 terawatt-hours [TWh]). It’s been replaced by natural gas (up 45%, or 400 TWh), renewables (up 260%, or 200 TWh), and increased efficiency (the US uses 9%, or 371 TWh less electricity than a decade ago).

US power grid

Evolution of the American power grid mix since 1960. Illustration: Carbon Brief

In other words, of the 866 TWh of lost coal power production, 46% was picked up by natural gas, 43% by increased efficiency, and 23% by renewables.

Natural gas is an unstable ‘bridge fuel’

While the shift away from coal is a positive development in slowing global warming by cutting carbon pollution, as Joe Romm has detailed for Climate Progress, research indicates that shifting to natural gas squanders most of those gains. For example, a 2014 study published in Environmental Research Letters found that when natural gas production is abundant, it crowds out both coal and renewables, resulting in little if any climate benefit. Part of the problem is significant methane leakage from natural gas drilling.



Switching to electric cars is key to fixing America's 'critically insufficient' climate policies

Posted on 22 January 2018 by dana1981

In order to meet its share of the carbon pollution cuts needed to achieve the 2°C Paris international climate target, America’s policies are rated as “critically insufficient” by the Climate Action Tracker. The Trump Administration has taken every possible step to undo the Obama Administration’s climate policies, including announcing that America will be the only world country to withdraw from the Paris agreement, and trying to repeal the Clean Power Plan.

In 2020, the next American president will have to make up the lost ground and come up with a plan to rapidly accelerate the country’s transition away from fossil fuels. Currently, transportation and power generation each account for about 30% of US greenhouse gas emissions, so those sectors represent the prime targets for pollution cuts. 

Carbon pollution from electricity is already falling fast

American power sector carbon emissions had exceeded those from transportation from 1979 until 2016. But because coal power plants have rapidly been replaced by natural gas and renewables, US power sector emissions have fallen rapidly since 2007, and are now below 1989 levels. US carbon pollution from transportation, on the other hand, has been on the rise since 2012. It remains higher than in 2000, nearly 20% higher than 1989 levels, and has surpassed power sector emissions.

sector emissions

US Energy Information Administration data on carbon pollution from the transportation and power sectors since 1973 (2017 estimated from the first 9 months of data) Illustration: Dana Nuccitelli



Scott Pruitt insincerely asked what's Earth's ideal temperature. Scientists answer

Posted on 17 January 2018 by dana1981

In an interview with Reuters last week, Trump’s EPA administrator Scott Pruitt said,

The climate is changing. That’s not the debate. The debate is how do we know what the ideal surface temperature is in 2100?

Pruitt’s goal is to sow doubt on behalf of his oil industry allies in order to weaken and delay climate policies. Shifting the ‘debate’ toward ‘the ideal surface temperature’ achieves that goal by creating the perception that we don’t know what temperature we should aim for. It’s in line with his boss’ recent ignorant tweet suggesting that “Perhaps we could use a little bit of that good old Global Warming.”

I spoke with a number of climate scientists who agreed that to minimize the risks associated with rapid human-caused climate change, from a practical standpoint the ‘ideal temperature’ is as close to the current one as possible.

Temperature isn’t the issue - temperature change is

Stefan Rahmstorf, Head of Earth System Analysis at the Potsdam Institute for Climate Impact Research pointed out that we’re not concerned about specific temperatures; it’s rapid temperature changes that cause problems:

Pruitt of course is trying to have a strawman debate, distracting from the fact that not a certain temperature as such is better or worse, but that a change from what we are adapted to is a problem, especially a very rapid change - in either direction, cooling or warming, this causes big disruption.

We should not stray too far away from what we and the currently existing ecosystems have evolved for. That is the optimum, simply because it is what we’re highly adapted to, and any major change is going to be very painful.

Civilization developed in a stable climate

Texas Tech’s Katharine Hayhoe agreed, noting that human civilization has developed in the relatively stable climate of the past 10,000 years.



The 'imminent mini ice age' myth is back, and it's still wrong

Posted on 9 January 2018 by dana1981

This post has been incorporated into the rebuttal to the myth A grand solar minimum could trigger another ice age

Roughly every two years we’re treated to headlines repeating the myth that Earth is headed for an imminent “mini ice age.” It happened in 20132015, and again just recently at the tail end of 2017.

This time around, the myth appears to have been sparked by a Sky News interview with Northumbria University mathematics professor Valentina Zharkova. The story was quickly echoed by the Daily MailInternational Business TimesSputnik NewsMetroTru News, and others. Zharkova was also behind the ‘mini ice age’ stories in 2015, based on her research predicting that the sun will soon enter a quiet phase.

The most important takeaway point is that the scientific research is clear – were one to occur, a grand solar minimum would temporarily reduce global temperatures by less than 0.3°C, while humans are already causing 0.2°C warming per decade

solar minimum temp

The global mean temperature difference is shown for the time period 1900 to 2100 for the IPCC A2 emissions scenario. The red line shows predicted temperature change for the current level of solar activity, the blue line shows predicted temperature change for solar activity at the much lower level of the Maunder Minimum, and the black line shows observed temperatures through 2010. Illustration: Adapted from Feulner & Rahmstorf (2010) in Geophysical Research Letters by

So the sun could only offset at most 15 years’ worth of human-caused global warming, and once its quiet phase ended, the sun would then help accelerate global warming once again.



2017 was the hottest year on record without an El Niño, thanks to global warming

Posted on 2 January 2018 by dana1981

2017 was the second-hottest year on record according to Nasa data, and was the hottest year without the short-term warming influence of an El Niño event:

1964–2017 global surface temperature data from Nasa, divided into El Niño (red), La Niña (blue), and neutral (black) years, with linear trends added.

In fact, 2017 was the hottest year without an El Niño by a wide margin – a whopping 0.17°C hotter than 2014, which previously held that record. Remarkably, 2017 was also hotter than 2015, which at the time was by far the hottest year on record thanks in part to a strong El Niño event that year.

For comparison, the neutral El Niño conditions and the level of solar activity in 1972 were quite similar to those in 2017. 45 years later, the latter was 0.9°C hotter than the former. For each type of year – La Niña, El Niño, and neutral – the global surface warming trend between 1964 and 2017 is 0.17–0.18°C per decade, which is consistent with climate model predictions.



Fake news is a threat to humanity, but scientists may have a solution

Posted on 27 December 2017 by dana1981

People are very good at finding ways to believe what we want to believe. Climate change is the perfect example – acceptance of climate science among Americans is strongly related to political ideology. This has exposed humanity’s potentially fatal flaw. Denying an existential threat threatens our existence.

But that’s exactly what many ideological conservatives doPartisan polarization over climate change has steadily grown over the past two decades. This change can largely be traced to the increasingly fractured and partisan media environment that has created an echo chamber in which people can wrap themselves in the comfort of “alternative facts” (a.k.a spin and lies) that affirm their worldviews. We’ve become too good at fooling ourselves into believing falsehoods, which has ushered in a dangerous “post-truth” era, with no better example than the subject of climate change.

In its December 2017 issue, the Journal of Applied Research in Memory and Cognition published a paper by Stephan Lewandowsky, Ullrich Ecker, and John Cook, along with an impressive 9 responses from other social scientists, essentially investigating how we can make truth great again.

The Fox Newsification of America

The December 2017 Alabama special election provided an excellent example of the problem at hand. Despite numerous allegations and evidence that Roy Moore pursued and in some cases sexually assaultedteenage girls while in this thirties, 71% of Alabama Republicans believed the allegations were false. Among those disbelieving Republicans, approximately 90% said that the media and Democrats were behind the allegations. As Donald Trump would put it, they believed the allegations were “fake news.” Similarly, 51% of Republicans still believe that Barack Obama was born in Kenya.



Scientists have beaten down the best climate denial argument

Posted on 18 December 2017 by dana1981

Climate deniers have come up with a lot of arguments about why we shouldn’t worry about global warming – about 200 of them – but most are quite poor, contradictory, and easily debunked by consulting the peer-reviewed scientific literature. The cleverest climate contrarians settle on the least implausible argument – that equilibrium climate sensitivity (ECS – how much a doubling of the amount of carbon dioxide in the atmosphere will increase Earth’s surface temperature) is low, meaning that the planet will warm relatively slowly in response to human carbon pollution.

But they have to explain how that can be the case, because there are a lot of factors that amplify global warming. For example, a warmer atmosphere holds more water vapor, which is itself a greenhouse gas, adding further warming. Warming also melts ice, leaving Earth’s surface less reflective, absorbing more sunlight. There are a number of these amplifying ‘feedbacks,’ but few that would act to significantly slow global warming.

Clouds are one possible exception, because they both act to amplify global warming (being made of water vapor) and dampen it (being white and reflective). Which effect wins out depends on the type of cloud, and so whether clouds act to accelerate or slow global warming depends on exactly how the formation of different types of clouds changes in a hotter world. That’s hard to predict, so many contrarians have wishfully argued that clouds will essentially act as a thermostat to control global warming.

Denial101x lecture on cloud feedbacks by Peter Jacobs.



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