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Climate Hustle

Explaining climate change science & rebutting global warming misinformation

Scientific skepticism is healthy. Scientists should always challenge themselves to improve their understanding. Yet this isn't what happens with climate change denial. Skeptics vigorously criticise any evidence that supports man-made global warming and yet embrace any argument, op-ed, blog or study that purports to refute global warming. This website gets skeptical about global warming skepticism. Do their arguments have any scientific basis? What does the peer reviewed scientific literature say?


New rebuttal to the myth 'climate scientists are in it for the money' courtesy of Katharine Hayhoe

Posted on 23 November 2017 by Guest Author

We've used an excellent new video by Katharine Hayhoe as part of her Global Weirding series with PBS to create a new myth rebuttal - Climate scientists are in it for the money.  It's also accessible via the short URL



Analysis: WRI data suggests emissions have already ‘peaked’ in 49 countries

Posted on 22 November 2017 by Zeke Hausfather

This is a re-post from Carbon Brief

To avoid dangerous levels of global warming, the international community has pledged to limit global temperature rise to less than 2C above pre-industrial levels.

This commitment requires rapid and sustained reductions in greenhouse gas (GHG) emissions over the next few decades from all of the world’s major emitters. To meet this target, global emissions would likely have to peak in the next few years and decline 50% by the year 2050, according to the latest United Nations analysis.

new report published by World Resources Institute (WRI), a US-based global environmental research group, now suggests that 49 countries have already seen their emissions peak, representing around 36% of current global emissions. Another 8 countries representing another 23% of emissions have commitments to peak in the next decade or so.

Turning points

Using WRI’s data, Carbon Brief has created the interactive chart below. It shows the countries whose emissions have peaked in each decade, with the size of the bubble representing the relative size of that country’s emissions. The line at the bottom shows the percent of current global emissions represented by the peaking countries.



Video: Climate, Sea Level, and Superstorms

Posted on 21 November 2017 by greenman3610

Via Climate Crocks

This season’s disasters in the Caribbean and Gulf of Mexico re-started the conversation around climate and extreme weather. Several recent studies shine a light on this:



Battered by extreme weather, Americans are more worried about climate change

Posted on 20 November 2017 by dana1981

The latest climate change survey from Yale and George Mason Universities is out, and it shows that Americans are still poorly-informed about the causes of global warming. Only 54% understand that it’s mostly human-caused, while 33% incorrectly believe global warming is due mainly to natural factors. 

In fact, a new study published in Nature Scientific Reports developed a real-time global warming index. It shows that humans are responsible for 1°C global surface warming over the past 150 years – approximately 100% of the warming we’ve observed. Lead author Karsten Haustein explained their new index and study in a blog post.


Americans are nevertheless growing increasingly concerned about climate change. A record 22% are very worried about it (double the number in the March 2015 survey), and 63% of Americans are at least somewhat worried about climate change. That’s probably because they perceive direct climate impacts – 64% of survey participants think that global warming is affecting the weather, and 33% said it’s having a big influence.



2017 SkS Weekly Climate Change & Global Warming Digest #46

Posted on 19 November 2017 by John Hartz

Story of the Week... Toon of the Week... Quote of the Week... Coming Soon on SkS... Poster of the Week... Climate Feedback Reviews... SkS Week in Review... 97 Hours of Consensus...

Story of the Week...

UN Climate Talks Wrap Up with World Leaving Trump Behind

‘However much Trump wants to take us backward on climate change, the rest of the world — and the rest of the U.S. — is intent on moving forward.’

COP 23 Protestors 

While protesters outside the UN climate talks urged an end to coal, a broad range of climate supporters spoke up inside, including U.S. states, cities and businesses that support great global ambition to rein in climate change. Credit: Sascha Schuermann/AFP/Getty Images 

Two weeks of international climate talks in Bonn made only incremental progress toward resolving disputes that have been lingering since the Paris Agreement of 2015. The main achievement may have been cementing a firebreak to prevent the Trump administration from torching the whole process.

The strategy is to assert a broad new leadership among nations big and small, to bolster their resolve with high-profile commitments from American cities and states, to muster corporations and financial institutions in an attempt to kickstart renewable energy and assist poor countries, and to leave Washington isolated on the world stage.

It's a strategy pinned on the hopes—although diplomats would never put it so bluntly—that either Donald Trump will change his mind or that the United States will change its leader.

"The story of these climate talks was that however much Donald Trump wants to take us backward on climate change, the rest of the world—and the rest of the U.S.—is intent on moving forward," said Nathaniel Keohane, vice president for global climate at the Environmental Defense Fund. 

UN Climate Talks Wrap Up with World Leaving Trump Behind by John H Cushman Jr, InsideClimate News, Nov 16, 2017 



2017 SkS Weekly Climate Change & Global Warming News Roundup #46

Posted on 18 November 2017 by John Hartz

A chronological listing of news articles posted on the Skeptical Science Facebook page during the past week. 

Editor's Pick

‘Planet at a crossroads’: climate summit makes progress but leaves much to do

The UN negotiations in Bonn lay the groundwork for implementing the landmark Paris deal, but tough decisions lay ahead

COP23 Bonn Act Alliance Chocolate Coins

Representatives of Act Alliance hand out chocolate coins, promoting the need for climate finance for adaptation. Photograph: Kiara Worth/ENB/IISD

The world’s nations were confident they were making important progress in turning continued political commitment into real world action, as the global climate change summit in Bonn was drawing to a close on Friday.

The UN talks were tasked with the vital, if unglamorous, task of converting the unprecedented global agreement sealed in Paris in 2015 from a symbolic moment into a set of rules by which nations can combine to defeat global warming. Currently, the world is on track for at least 3C of global warming – a catastrophic outcome that would lead to severe impacts around the world.

The importance of the task was emphasised by Frank Bainimarama, Fiji’s prime minister and president of the summit: “We are not simply negotiating words on a page, but we are representing all our people and the places they call home.”

‘Planet at a crossroads’: climate summit makes progress but leaves much to do by Damian Carrington, Guardian, Nov 17, 2017 



New research, November 6-12, 2017

Posted on 17 November 2017 by Ari Jokimäki

A selection of new climate related research articles is shown below.

The figure is from paper #32.

Climate change impacts

1. Nitrogen availability dampens the positive impacts of CO2 fertilization on terrestrial ecosystem carbon and water cycles

"Results suggest that the rate of global GPP increase is overestimated by 85% during 2000-2015 without N limitation. This limitation is found to occur in many tropical and boreal forests, where a negative leaf N trend indicates a reduction in photosynthetic capacity, thereby suppressing the positive vegetation response to enhanced CO2 fertilization."

2. Climatic variability and dengue risk in urban environment of Delhi (India)

"Findings reveal significant changes in weather across the year having significant and positive association with dengue cases at specified lags. Weeks in April and July to October with gaps have been identified as the high risk weeks based on the estimated relative risk. There has been intra-annual expansion in dengue risk period extending beyond monsoon and post-monsoon."



California’s new law aims to tackle imported emissions

Posted on 16 November 2017 by Zeke Hausfather

This is a re-post from Carbon Brief

California has started a large investment in infrastructure. In early 2017, the US state approved $52bn in spending on repair and maintenance projects. As one of the most progressive states for emission reductions and proactive climate policy, California has been examining ways to ensure that its infrastructure investments minimise greenhouse gas emissions.

Jerry Brown, California’s governor, signed into law the Buy Clean California Act. The act requires that the state set a maximum “acceptable lifecycle global warming potential” for different building materials, specifying that only materials with embodied emissions below that level can be purchased by the state.

As the state government is the largest purchaser of steel and concrete in California, proponents hope that it can leverage its buying power to help promote lower-carbon production practices.

This represents the first time a US state is trying not only to reduce its own emissions, but to also reduce the emissions embodied in some of the goods that it imports. This could prove to be an important part of reducing the state’s overall contribution to climate change.

As Carbon Brief has previously reportedaround 22% of all global CO2 emissions stem from the production of goods that are traded internationally. About 6% of total US emissions are due to net imports of CO2 embodied in goods.

While steel and other construction materials purchased by the state represent only a small part of California’s total carbon emissions, this bill sets a precedent that imported goods can be regulated based on their lifecycle carbon impacts.



An Inconvenient Sequel – the science, history, and politics of climate change

Posted on 15 November 2017 by John Abraham

Al Gore’s new movie ‘An Inconvenient Sequel’ is, in some ways, similar to his groundbreaking Inconvenient Truth project, but different in other ways. Those key differences are why I recommend you watch it.

This movie successfully accomplishes a number of interweaving tasks. First, it gives some of the science of climate change. Gore gets his science right. I remember his first movie, which I thought was more steeped in science and data than this one, so based on my recollection this new picture is somewhat abbreviated. That’s a good thing because the science is settled on climate change. That is, the science is settled that humans are causing current climatic changes and the science is settled that we are observing these changes throughout the natural world. 

Readers of this column who venture into the comments below will likely find people claiming, “science is never settled.” But the people making those comments are not scientists. They don’t work in this field every day, they don’t see the data, and they don’t know what they’re talking about.

The opening of the new film shows a sample of the misguided attacks on Al Gore, exclusively from conservatives in the United States. It was so clear to me, when watching and listening, that these attacks are the same ones that we climate scientists constantly have to endure. Most scientists have not been attacked as consistently or for such a long duration as Mr. Gore, but the types of attacks he has had to handle are close cousins to what my colleagues and I experience on a regular basis. 



Analysis: Global CO2 emissions set to rise 2% in 2017 after three-year ‘plateau’

Posted on 14 November 2017 by Zeke Hausfather

This is a re-post from Carbon Brief

Over the past three years, global CO2 emissions from fossil fuels have remained relatively flat. However, early estimates from the Global Carbon Project (GCP) using preliminary data suggest that this is likely to change in 2017 with global emissions set to grow by around 2%, albeit with some uncertainties.

Hopes that global emissions had peaked during the past three years were likely premature. However, GCP researchers say that global emissions are unlikely to return to the high growth rates seen during the 2000s. They argue that it is more likely that emissions over the next few years will plateau or only grow slightly, as countries implement their commitments under the Paris Agreement.

2017 emissions likely to increase

The GCP is a group of international researchers who assess both sources and sinks of carbon. It has published an annual global carbon budget report since 2006. Its newly released global carbon budget for 2017 provides estimates of emissions by country, global emissions from land-use changes, atmospheric accumulation of CO2, and absorption of carbon from the atmosphere by the land and oceans.

Video summary of the findings of the GCP’s new 2017 global carbon budget, via Future Earth and the GCP.



On climate and global leadership, it's America Last until 2020

Posted on 13 November 2017 by dana1981

Five months ago, Trump quickly cemented his legacy as the country’s worst-ever president by inexplicably starting the process to withdraw from the Paris climate accords. With even war-torn Syria now signing the agreement, the leadership of every world country has announced its intent to tackle the existential threat posed by human-caused climate change, except the United States. 

View image on Twitter

While this decision may seem puzzling to the rest of the world, the explanation is simple - a study published two years ago found that the Republican Party is the only major political party in the world that rejects the need to tackle climate change, and we know that voters follow elite cues. In 2016, American voters made the terrible mistake of putting that party in charge of the entire federal government, including electing this man president:

The concept of global warming was created by and for the Chinese in order to make U.S. manufacturing non-competitive.



2017 SkS Weekly Climate Change & Global Warming Digest #45

Posted on 12 November 2017 by John Hartz

Story of the Week... El Niño/La Niña Update... Toon of the Week... Video of the Week... Coming Soon on SkS... Poster of the Week... Climate Feedback Reviews... SkS Week in Review... 97 Hours of Consensus...

Story of the Week...

COP23: Writing the Paris accord rule book

Having agreed to limit global warming, the COP must now figure out how to measure progress toward the goals set in Paris. Without double-checking this progress, the climate goals won't be reached.

COP23 Bonn Germany 

Two years after the world committed to climate action in Paris, negotiators are still trying to figure out the nuts and bolts of the global deal to limit global warming to less than 2 degrees Celsius.

A big part of that is developing a plan to monitor and verify the pledges made by nearly 200 countries to reduce greenhouse gas emissions. During the two-week long COP23 talks in Bonn, negotiators are focusing, in part, on developing a system to make those measurements.

Writing that rule book is no easy task, says University of Edinburgh climate scientist Paul Palmer, part of an international team that assesses heat-trapping gases in the atmosphere.

"We need to measure carefully. We'll be looking for small, gradual reductions of large numbers, so we need to make sure we get the numbers right," Palmer told DW.

COP23: Writing the Paris accord rule book by Bob Berwyn, Deutsche Welle (DW), Nov 7, 2017



2017 SkS Weekly Climate Change & Global Warming News Roundup #45

Posted on 11 November 2017 by John Hartz

A chronological listing of news articles posted on the Skeptical Science Facebook page during the past week. 

Editor's Pick

Conservatives probably can’t be persuaded on climate change. So now what?

One more round of “messaging” won’t do it.

Mapping Climate Change Hot Spots 

When it comes to climate change, US conservatives inhabit a unique position, as part of the only major political party in the democratic world to reject the legitimacy of climate science and any domestic policy or international agreement meant to address it. Instead, the GOP is working actively to increase production and consumption of fossil fuels and to slow the transition to renewable energy.

How can conservatives be moved on climate change?

I recently heard a podcast that helped me order my thoughts on this perennial debate. It was Political Research Digest, a weekly 15-minute research round-up hosted by Michigan State University political scientist Matt Grossman for the Niskanen Center. (Grossman is the author of Asymmetric Politics, a crucial text for understanding American political parties. The podcast is nerdy and good.)

In the third episode, Grossman takes a look at some recent literature on climate change opinion and how, if at all, it can be shifted among conservatives.

It begins well, with an excellent lay of the land. But the discussion of how to move forward goes off course, in a very familiar way. It stops short of contemplating the uncomfortable but increasingly likely possibility that persuading conservatives on this subject has become impossible, and what that might mean for those concerned about the looming dangers of climate change.

Let’s start with a look a few basic facts about public opinion on climate.

Conservatives probably can’t be persuaded on climate change. So now what? by David Roberts, Energy & Environment, Vox, Nov 10, 2017  



New research, October 30 - November 5, 2017

Posted on 10 November 2017 by Ari Jokimäki

A selection of new climate related research articles is shown below.

The graph is from paper #80.

Climate change

1. Observed warming over northern South America has an anthropogenic origin

"Results indicate that the recently observed warming in the dry seasons is well beyond the range of natural (internal) variability. In the wet season the natural modes of variability explain a substantial portion of Tmin and Tmax variability. We demonstrate that the large-scale component of greenhouse gas (GHG) forcing is detectable in dry-seasonal warming. However, none of the global and regional climate change projections reproduce the observed warming of up to 0.6 K/Decade in Tmax in 1983–2012 over northern SA during the austral spring (SON). Thus, besides the global manifestation of GHG forcing, other external drivers have an imprint."

2. Observed changes in temperature extremes over Asia and their attribution

"We determined that the warming trend was inconsistent with the natural variability of the climate system but agreed with climate responses to external forcing as simulated by the models. The anthropogenic and natural signals could be detected and separated from each other in the region for almost all indices, indicating the robustness of the warming signal as well as the attribution of warming to external causes."

3. Reduced cooling following future volcanic eruptions

"Using earth system model simulations we find that the eruption-induced cooling is significantly weaker in the future state. This is predominantly due to an increase in planetary albedo caused by increased tropospheric aerosol loading with a contribution from associated changes in cloud properties."



“Toasted, roasted and grilled” or already over the hump?

Posted on 9 November 2017 by dana1981

Last week news stories came out that said that global human carbon emissions may have peaked, essentially implying that we could already be over the hump and on the way to solving climate change—while other news stories that same day and in that same publication noted that atmospheric carbon dioxide concentrations jumped by a record amount in 2016These stories exemplify the emotional roller coaster that often comes with following climate change news. How can we reconcile the ebbs and flows between hopeful and apocalyptic climate stories?

The answer lies in considering the timeframe around a piece of climate news. For example, the seeming contradiction in the two news reports is explained by the monsterEl Niño event of 2016 that intensified droughts and consequently weakened the ability of vegetation to absorb carbon dioxide—showing that while human carbon pollution is responsible for the long-term rise in atmospheric concentrations, there is still ample short-term natural variation.

To give a second example: In a recent story, the managing director of the International Monetary Fund was quoted saying: “If we don't do anything about climate change now, in 50 years' time we will be toasted, roasted and grilled.” While that is an alarming statement, it focuses on a potential scenario in which half-a-century from now we have failed to change the course of our climate policies.

It’s important to remember, however, that with the international Paris climate accords, nearly every nation in the world agreed to begin the process to alter that worst-case course.



Rapid CO2 cuts could allow some cool-water corals to adapt to global warming

Posted on 8 November 2017 by Guest Author

This is a re-post from Carbon Brief by Daisy Dunne

Some of the world’s most diverse coral reefs are found in cooler parts of the tropics. These corals may be able to adapt to rising temperatures if future greenhouse gas emissions are drastically reduced, a new study suggests.

The modelling study simulates the effect of climate change on the survival of one population of a single coral species found off the coast of Rarotonga in the Cook Islands in the South Pacific. The researchers find that the genetic makeup of some cool-water corals might allow them to adapt to gradual increases in temperature.

However, without rapid cuts to emissions, the rate of climate change will likely outpace the ability of the corals to adapt, the study finds, resulting in the extinction of many coral populations by the end of the century.

More research will be needed to see if other cool-water corals around the world also hold the genetic code needed to adapt, another scientist tells Carbon Brief.



What do Jellyfish teach us about climate change?

Posted on 7 November 2017 by John Abraham

What do Jellyfish teach us about climate change?

A lot. At least that’s what I learned after reading a very recent paper out in the journal Global Climate Change. The article, “Ocean acidification alters zooplankton communities and increases top-down pressure of a cubazoan predator,” was authored by an international team of scientists – the paper looks at impacts of climate change on life in the world’s oceans.

I recall attending a horse-pulling contest as a child. The announcer at the event said something strange that stuck with me all these years. He said that two horses pulling a load at the same time are more effective than if the two horses pulled separately and their loads were added. That is, something about two horses working together made them greater than the sum of their parts. This study is a lot like those horses.

To begin, ocean acidification refers to the changing pH of ocean waters. As humans emit more greenhouse gases (carbon dioxide in particular) into the atmosphere, the chemistry of the oceans change. The effect is that the creatures living in the oceans are experiencing an environmental change that is separate from changing temperatures due to global warming. Scientists want to know how these changes will affect creatures, in particular because the biodiversity in the oceans is so very important to us as humans.

There has been some reporting on studies of calcifying organisms and their susceptibility to changing chemistry in the oceans. For instance, echinoderms, molluscs, corals, and crustaceans have been studied in laboratories and in situ. The studies show that acidification reduces development and survival. Acidification can alter the way these creatures make and maintain their shells.

But the authors of this new study point out that there are many other non-calcifying organisms that may also be impacted by acidification. Even for these creatures, acidification has been shown to have deleterious effects that result in reduced survival, reduced reproductivity, and reduced size.



We have every reason to fear Trump’s pick to head NASA

Posted on 6 November 2017 by dana1981

Unlike past Nasa administrators, Trump nominee Jim Bridenstine doesn’t have a scientific background. He’s a Republican Congressman from Oklahoma and former Navy pilot. He also has a history of denying basic climate science. That’s concerning because Nasa does some of the world’s best climate science research, and Bridenstine previously introduced legislation that would eliminate Earth science from Nasa’s mission statement.

At his Senate hearing last week, Bridenstine tried to remake his image. He said that his previous science-denying, politically polarizing comments came with the job of being a Republican congressman, and that as Nasa administrator he would be apolitical. A kinder, gentler Bridenstine. But while he softened his climate science denial, his proclaimed new views remain in line with the rest of the harshly anti-science Trump administration. That’s very troubling.

A gentler form of climate science denial

The standard Trump administration position on climate change, held by administration officials like EPA Administrator Scott Priutt and Energy Secretary Rick Perry, is that humans are contributing to global warming, but we don’t know how much. Bridenstine repeated that position in a tense exchange with Senator Brian Schatz (D-HI).



2017 SkS Weekly Climate Change & Global Warming Digest #44

Posted on 5 November 2017 by John Hartz

Story of the Week... Toon of the Week... SkS in the News... SkS Spotlights... Video of the Week... Coming Soon on SkS... Poster of the Week... Climate Feedback Reviews... SkS Week in Review... 97 Hours of Consensus...

Story of the Week...

U.S. Report Says Humans Cause Climate Change, Contradicting Top Trump Officials

Record Temps in Phoenix AZ June 2017 

Phoenix experienced record highs in June. The report says there are “no convincing alternative explanations” other than human activity to account for rising global temperatures. Credit Ralph Freso/Getty Images

Directly contradicting much of the Trump administration’s position on climate change, 13 federal agencies unveiled an exhaustive scientific report on Friday that says humans are the dominant cause of the global temperature rise that has created the warmest period in the history of civilization.

Over the past 115 years global average temperatures have increased 1.8 degrees Fahrenheit, leading to record-breaking weather events and temperature extremes, the report says. The global, long-term warming trend is “unambiguous,” it says, and there is “no convincing alternative explanation” that anything other than humans — the cars we drive, the power plants we operate, the forests we destroy — are to blame.

The report was approved for release by the White House, but the findings come as the Trump administration is defending its climate change policies. The United Nations convenes its annual climate change conference next week in Bonn, Germany, and the American delegation is expected to face harsh criticism over President Trump’s decision to walk away from the 195-nation Paris climate accord and top administration officials’ stated doubts about the causes and impacts of a warming planet.  

U.S. Report Says Humans Cause Climate Change, Contradicting Top Trump Officials by Lisa Friedman & Glenn Trush, Climate, New York Times, Nov 3, 2017 



2017 SkS Weekly Climate Change & Global Warming News Roundup #44

Posted on 4 November 2017 by John Hartz

A chronological listing of news articles posted on the Skeptical Science Facebook page during the past week. 

Editor's Pick

There’s a huge gap between the Paris climate change goals and reality

Current pledges are about a third of what’s needed.

Coal-fired power plant in Wyoming 

Coal-fired power plant in Wyoming 

n 2015 in Paris, the countries of the world agreed to hold the rise in global average temperatures to “well below 2°C above pre-industrial levels and pursue efforts to limit the temperature increase to 1.5°C above pre-industrial levels.”

How’s that going?

The unavoidably grim answer: not well, and not just because President Donald Trump has promised to pull the United States out of the accord.

Every year, the United Nations Environment Program (UNEP) releases an “Emissions Gap” report, on the remaining disparity between the world’s stated ambitions on climate and the actions it is currently taking. The 2017 edition of the report is out a week before the next round of international climate talks in Bonn, Germany. And it reports that the gap remains ... substantial.

Researchers calculate that for a reasonable chance of hitting our goal, global greenhouse gas emissions must peak by 2020 and the gap must be closed by 2030 — in other words, if we are not on the right trajectory by 2030, all hope of 1.5 degrees is lost and 2 degrees is almost certainly out of reach as well.

Let’s run through a few of the top-line conclusions of the report, which was assembled by an international team of scientists based on the most recent published science. 

There’s a huge gap between the Paris climate change goals and reality by David Roberts, Energy & Environment, Vox, Oct 31, 2017



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