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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?


Why does land warm up faster than the oceans?

Posted on 22 September 2020 by Guest Author

This is a re-post from Carbon Brief by Dr. Michael Byrne

Last year, global temperatures were 0.95C warmer than the 20th century average. Human activity is responsible for around 100% of this warming.

Delving a little deeper into these figures shows that the Earth’s land areas were 1.43C warmer than average, while the oceans were 0.77C warmer. This is evidence of how the world’s continents have warmed more rapidly than its oceans over recent decades. 

This contrast between land and ocean temperature change will strongly shape the global pattern of future warming and has important implications for humans. We are, after all, a species that much prefers to live on land.

But what drives this warming contrast? It’s a deceptively simple question, but one with a much-misunderstood answer. In this guest post, I outline a robust, quantitative theory for the land-ocean warming contrast that has only been developed in recent years.

Heat capacity

Simple physics suggests that when you put more heat into the climate system, land should warm more quickly than oceans. This is because land has a smaller “heat capacity” than water, which means it needs less heat to raise its temperature.

The chart below shows how the Earth’s land surface (yellow line) has warmed more rapidly than the ocean (dark blue) over the observational record.



Wind and solar are 30-50% cheaper than thought, admits UK government

Posted on 21 September 2020 by Guest Author

This is a re-post from Carbon Brief by Simon Evans

Electricity generated from wind and solar is 30-50% cheaper than previously thought, according to newly published UK government figures.

The new estimates of the “levelised cost” of electricity, published this week by the Department for Business, Energy and Industrial Strategy (BEIS), show that renewables are much cheaper than expected in the previous iteration of the report, published in 2016.

The previously published version had, in turn, already trimmed the cost of wind and solar by up to 30%. As a result, electricity from onshore wind or solar could be supplied in 2025 at half the cost of gas-fired power, the new estimates suggest.

The new report is the government’s first public admission of the dramatic reductions in renewable costs in recent years. It had previously carried out internal updates to its cost estimates, in both 2018 and 2019, but these were never published despite repeated questions in parliament.

The BEIS report also presents new estimates of the “enhanced levelised cost” of different technologies, which reflects any wider system benefits and their “system integration costs”.

These alternative figures, which have been under development for several years, put gas with carbon capture and storage (CCS) in a particularly favourable light, with costs comparable to wind or solar. CCS is expected to feature in the upcoming energy white paper, due this autumn.



2020 SkS Weekly Climate Change & Global Warming Digest #38

Posted on 20 September 2020 by John Hartz

Story of the Week... Toon of the Week... Coming Soon on SkS... Climate Feedback Claim Review... SkS Week in Review... Poster of the Week...

Story of the Week...

The tipping points at the heart of the climate crisis

Many parts of the Earth’s climate system have been destabilised by warming, from ice sheets and ocean currents to the Amazon rainforest – and scientists believe that if one collapses others could follow

Thwaites Glacier in Antarctica

The Thwaites glacier in Antarctica, where ice is now melting on a massive scale. Photograph: Nasa/OIB/Jeremy Harbeck/EPA 

The warning signs are flashing red. The California wildfires were surely made worse by the impacts of global heating. A study published in July warned that the Arctic is undergoing “an abrupt climate change event” that will probably lead to dramatic changes. As if to underline the point, on 14 September it was reported that a huge ice shelf in northeast Greenland had torn itself apart, worn away by warm waters lapping in from beneath.

That same day, a study of satellite data revealed growing cracks and crevasses in the ice shelves protecting two of Antarctica’s largest glaciers – indicating that those shelves could also break apart, leaving the glaciers exposed and liable to melt, contributing to sea-level rise. The ice losses are already following our worst-case scenarios.

These developments show that the harmful impacts of global heating are mounting, and should be a prompt to urgent action to cut greenhouse gas emissions. But the case for emissions cuts is actually even stronger. That is because scientists are increasingly concerned that the global climate might lurch from its current state into something wholly new – which humans have no experience dealing with. Many parts of the Earth system are unstable. Once one falls, it could trigger a cascade like falling dominoes.

Click here to access the entire aticle as originally posted on the Observer/Guardian website. 

The tipping points at the heart of the climate crisis by Michael Marshall, The Observer/The Guardian, Sep 19, 2020



2020 SkS Weekly Climate Change & Global Warming News Roundup #38

Posted on 19 September 2020 by John Hartz

A chronological listing of news articles linked to on the Skeptical Science Facebook Page during the past week: Sun, Sep 13, 2020 through Sat, Sep 19, 2020

Editor's Choice

Get to Net-Zero by Mid-Century? Even Some Global Oil and Gas Giants Think it Can Be Done

A report by a think tank whose members include the oil giants BP and Shell, as well as some environmental groups, suggests how it could be done and at what cost.

Renewable Energy Compex in China

Aerial view of a wind-solar hybrid photovoltaic power station on September 12, 2020 in Zaozhuang, Shandong Province of China. Credit: Li Zongxian/VCG via Getty Images

The world must get to net-zero carbon emissions by mid-century, and can make it happen for a cost that is relatively small in global terms, $1 trillion to $2 trillion per year, a new report has concluded.

The report was released this week by the Energy Transitions Commission, a think tank whose members include global industry giants like BP.

The report said that electricity should replace fossil fuels across the economy, rather than setting up systems that allow for some emissions that would need to be offset by carbon-removal technologies. Researchers and environmental groups have been saying similar things for years, but the message may be more influential coming from an organization tied to big businesses.

"An exercise like this, done with this group of people, has more political heft than if it was a bunch of academics in the basement," said David Victor, an international relations professor at the University of California San Diego and co-chair of the Brookings Institution's energy and climate initiative.

Click here to access the entire article originally publshed on the InsideClimate News website.

Get to Net-Zero by Mid-Century? Even Some Global Oil and Gas Giants Think it Can Be Done by Dan Gearino, InsideClimate News, Sep 17, 2020



Highlighting some expert interviews from Denial101x

Posted on 18 September 2020 by Guest Author, BaerbelW

This is a guest blog post based on a comment by Guy Dusselier we happened upon in the discussion forums for week five about climate change impacts in our MOOC Denial101x. The words are Guy's and we added the videos he mentions where they fit in.

All along we have witnessed and enjoyed a long procession of experts in many fields of climate science & expertise in related specific domains. First, I truly think that we should be ever so grateful that the world has so many excellent people from all over the world dedicated to this top priority supra-national emergency.

The lectures are always instructive and very helpful in understanding some of the science on a practical level. But often, many of the full interviews are quite revealing and at times bring the "inner" person behind - or should I rather say - inside the scientist.

Some of this week's range of full interviews has touched me more than once, but for different reasons.

Sir David Attenborough, for example, is an icon who through his documentaries has enabled everybody to zoom in on issues that mattered (and matters more than ever!) for our planet. He weighs his words, does not fill time with unnecessary words, rather using his experience and authority to create impact.

Richard Alley drips with enthusiasm and makes his pitch light-hearted. What is important to convey to the public, he does in his own casual and honest way. He masters the skill to bring something (climate science) near which otherwise would remain distant and elusive.



Berkeley study: 90% carbon-free electricity achievable by 2035

Posted on 17 September 2020 by greenman3610

This is a re-post from Yale Climate Connections

Imagine the U.S., over the next 15 years, achieving 90% carbon-free, “clean” electricity.

No need to just imagine, better yet read about it. That’s the conclusion of a new University of California Berkeley study “2035 – The Report: Plummeting Solar, Wind, and Battery Costs Can Accelerate Our Clean Energy Future,” by the university’s Goldman School of Public Policy. The report is featured in the current installment of videographer Peter Sinclair’s “This Is Not Cool” video.

That goal – 90% carbon-free electricity by 2035 – can be achieved without increasing consumer electricity costs “at all,” says Dan Kammen, PhD, of Berkeley. Solar, wind, and storage costs have fallen so significantly, he says, that “even conservative leaders, conservative states, districts, countries can legitimately look at renewables, and actually economically need to look at renewables, as their next purchases.”

Study author Amol Phadke, PhD, says that costs “have dropped so much that renewables have become cost-effective across the country” and no longer solely in particular regions of the U.S.

U.C. Santa Cruz’s Leah Stokes, PhD, says policies are needed to support efforts involving, for instance, energy conservation and commercial building efficiency and residential retrofits

Kammen, Phadke, and Stokes join with consulting firm Energy Innovations Vice President Sonia Aggerwal in arguing that renewables create three times more jobs per investment dollar than fossil fuels.

MacArthur “genius” fellow Saul Griffith, in a clip included in the video, cautions advocates of renewable energy against “demonizing” the fossil fuel industry: “We are getting the fossil fuel industry sort of backed into a corner,” Griffith says in that video. “And honestly, the most people in this country who know how to build infrastructure at scale are in the fossil fuel industry.”

Asked if the U.S. can afford to move to renewables, Nobel Prize economist and New York Times columnist Paul Krugman, PhD, says he is not worried: “Should it be a problem for us to borrow now and service that debt afterwards?” He answers his own question: “The arithmetic says it’s no problem.

“The debt implications – if it’s my top 10 things to worry about – it’s not in that top 10 list.”



Skeptical Science New Research for Week #37, 2020

Posted on 16 September 2020 by doug_bostrom


Viability of greenhouse gas removal via the artificial addition of volcanic ash to the ocean  (not open access, unfortunately) walks us through the numbers on a particular means of CO2 removal, addition of volcanic tephra to the ocean. The mechanism is straight chemistry and the cost is fully an order of magnitude less than other proposed methods. For the world population and emissions of approximately 4.982 metric tons per capita (2014) we're looking at the number above in US dollars per year to entirely solve our global emissions problem (assuming the system would scale so large). Roughly US$ 2 quadrillion/year, done cheap. Surely  there's a less expensive way? What could it be?

In fairness to authors Longman, Palmer and Gernon, they're certainly not proposing to entirely solve our CO2 problem with this intriguing and objectively efficient method. The admirable affordability of the scheme resulting still in such ballooning numbers is simply another indicator that we need to start with reduction of CO2 emissions, push the biggest and easiest button. 


Until this edition of New Research we've been using an indigenous tool to assist with identifying open access documents. Recently somebody dropped a clue brick on our heads (thanks David!) and made us aware of Unpaywall operates a sophisticated, legally respectful system to identify open access publications. Further investigation revealed an API for accessing their database. Although our own system performed remarkably well in comparison to Unpaywall, it required steady drain from a limited pool of time to maintain and as well was never going to match Unpaywall results. With this edition we've integrated the Unpaywall API. 

Practical effects:

  • As before, open access items are flagged.
  • Items found in the Unpaywall system will feature at minimum a permanent DOI access link, one that does not change when/if a publication changes notional URLs leading to articles.
  • When available, direct links to PDF versions of articles are presented. Clicking "PDF" for a article offering this option will directly load a paper.
  • As Unpaywall does not catch preprints notices that we cover, each edition of New Research will be reprocessed some weeks after publication, to update meta information.

98 Articles

Observations of global warming & effects

Precipitation–Radiation–Circulation Feedback Processes Associated with Structural Changes of the ITCZ in a Warming Climate during 1980–2014: An Observational Portrayal

Temperature trends in the northwestern Tibetan Plateau constrained by ice core water isotopes over the past 7,000 years

Fast local warming of sea-surface is the main factor of recent deoxygenation in the Arabian Sea
Open Access PDF DOI: 10.5194/bg-2020-325

Weakening Atlantic overturning circulation causes South Atlantic salinity pile-up
DOI: 10.1038/s41558-020-0897-7




A first-hand look: What it's like to live in a 2020 California wildfire evacuation zone

Posted on 15 September 2020 by Guest Author

This is a re-post from Yale Climate Connections by Daisy Simmons

It felt like 100 degrees in my in-laws’ Grass Valley, California, kitchen, but at least the lights were on and for the moment we were safely “distanced” from the Jones Fire. We’d just finished dessert, after pizza and a movie – even though it was Monday in what was to have been the first week of school.

One dessert down, and yet another? “But it’s evacuation night!” my now second-grader said, the best case I’ve heard for bonus dessert (and then some). Obviously we relented. 

A first-person perspective

Many of my conversations, as a mom living in California in 2020, seem to go this way now. Did we survive the disaster du jour? Yes. Great, now let’s console ourselves with chocolate, wine (but not too much, in case we have to evacuate again in the middle of the night), and staying up past everyone’s bedtime because no one can sleep anyway.

Ours is no isolated experience. As a former deputy director of Cal Fire had put it, our part of the state has been experiencing “a four-fer, with COVID, a heat wave, wildfires, and the threat of rolling power outages.”

Yes, as if a pandemic and distance learning and social turmoil weren’t enough, now we’re back to fire season. And this year, for the first time since I moved to California around 20 years ago, I’m learning what it’s like to be an evacuee.

My first evacuation after ‘high-low sirens wailing’

The night before our evacuation, I woke at 2 a.m. to the nightmarish sound of dry lightning outside our Nevada City home. We’d been under a Red Flag Warning, so my mind was already on high alert for exactly this dangerous weather condition. Anxiously counting one-one-thousands between thunder and lightning, I felt a brief surge of relief when rain began to fall – only to stop a meaningless 60 seconds later. But after what felt like months, but was probably minutes, I could see there were no fires visible from my window and that the lightning had passed. I checked my phone for alerts, and, finding there were none, returned to bed and tried to coax myself back to sleep.

The next morning, Meshawn, my partner, calmly told me that a fire had indeed started locally that night, over by Jones Bar, a once-idyllic watering hole on our beloved Yuba River. It was less than 10 miles down the country highway that runs adjacent to our home. But, she assured me, it was possible firefighters could get it under control. Then she left for work.

By midday, evacuation orders dotted the county’s new emergency dashboard, creeping closer to our downtown neighborhood.

The order hadn’t yet made it to our street, but when we heard the high-low sirens wailing down the highway behind us, alerting residents across the street that they need to evacuate, we figured that was close enough. It was time to go.



My Climate Story: Coming full Circle

Posted on 14 September 2020 by BaerbelW

This blog post is a follow up to my recap of Al Gore's Climate Reality Leadership Training I recently participated in. One of the exercises we were asked to complete was to write about our respective "Climate Story". This is a slightly updated version to the one I had submitted during the training.


I’ve always been interested in environmental topics and became a member of organisations like the WWF and Greenpeace while still in school many decades ago. Closer to home, I joined an NGO focused on local conservation activities and in 1991 became a volunteer docent at the “Wilhelma”, the zoological and botanical garden in Stuttgart, southern Germany. Due to these activities, I was somewhat aware of climate change but it hadn’t been my main focus which was more on wildlife-related topics like the bushmeat crisis, poaching, deforestation and more. This all changed rather quickly after watching Al Gore’s documentary “An Inconvenient Truth” in - IIRC - 2007 when the film became available in Germany. Shortly after watching the film, I read the accompanying book followed by many others like Elizabeth Kolbert’s “Field Notes from a Catastrophe”, Mark Lynas’ “Six Degrees” or Tim Flannery’s “We Weathermakers” to name just a few.

I also searched for information on the internet where I discovered “Wonderingmind42” -  science teacher Greg Craven - and his “most terrifying video you’ll ever see” on YouTube. This in turn led me to discover his dozens of follow-up videos titled “How it all ends” netting 7+ hours of viewing pleasure as well as the “Manpollo” website and discussion forum one of Greg’s fans had set up to talk about the videos. One thing led to another and all of a sudden I was coordinating translation activities for the subtitles of Greg’s videos and the “Manpollo”-team helped Greg to write his book “What’s the worst that could happen?” which was published in 2009.


While helping with Greg’s book, I happened upon the website Skeptical Science (SkS) which debunks climate misinformation and for which its founder John Cook had just added translation capabilities. By then, I felt knowledgeable enough about the topic to contact John offering to help with translations into German. John quickly updated my SkS account to give me the required access at the beginning of 2010 and a little while later a small team was working on German translations of selected SkS content. As time passed, I also published a blog post now and then for SkS, took over the coordination of all translation activities for the website (by now 25 languages!) and even became co-author of several peer-reviewed studies about the scientific consensus on human-caused global warming (Cook et al. 2013 & 2016 and Skuce et al. 2017).



2020 SkS Weekly Climate Change & Global Warming Digest #37

Posted on 13 September 2020 by John Hartz

Story of the Week... La Niña Update... Toon of the Week... Quote of the Week... Coming Soon on SkS...  Poster of the Week... SkS Week in Review...

Story of the Week...

Humans exploiting and destroying nature on unprecedented scale – report

Animal populations have plunged an average of 68% since 1970, as humanity pushes the planet’s life support systems to the edge 

Soybean Harvest in Campo Verde, Brazil

Mass soybean harvesting in Campo Verde, Brazil. Intensive agricultures has contributed to the collapse of some animal populations. Photograph: Alffoto/WWF

Wildlife populations are in freefall around the world, driven by human overconsumption, population growth and intensive agriculture, according to a major new assessment of the abundance of life on Earth.

On average, global populations of mammals, birds, fish, amphibians and reptiles plunged by 68% between 1970 and 2016, according to the WWF and Zoological Society of London (ZSL)’s biennial Living Planet Report 2020. Two years ago, the figure stood at 60%.

The research is one of the most comprehensive assessments of global biodiversity available and was complied by 134 experts from around the world. It found that from the rainforests of central America to the Pacific Ocean, nature is being exploited and destroyed by humans on a scale never previously recorded.

The analysis tracked global data on 20,811 populations of 4,392 vertebrate species. Those monitored include high-profile threatened animals such as pandas and polar bears as well as lesser known amphibians and fish. The figures, the latest available, showed that in all regions of the world, vertebrate wildlife populations are collapsing, falling on average by more than two-thirds since 1970.

Click here to acess the entire article originally published on the The Guardian website.

Humans exploiting and destroying nature on unprecedented scale – report by Patrick Greenfield, Environment, Guardian, Sep 9, 2020



2020 SkS Weekly Climate Change & Global Warming News Roundup #37

Posted on 12 September 2020 by John Hartz

A chronological listing of news articles linked to on the Skeptical Science Facebook Page during the past week: Sun, Sep 6, 2020 through Sat, Sep 12, 2020

Editor's Choice

With California ablaze, Newsom blasts Trump administration for failing to fight climate change

Wildfire in Oroville, CA in Sep, 2020

Trinity River Conservation Camp crew members drown embers Friday in Oroville. (Brian van der Brug / Los Angeles Times)

Standing among charred trees in Oroville, Gov. Gavin Newsom insisted that California will do more to fight climate change and took the Trump administration to task for its policies that reduce environmental protections.

“People that want to roll back vehicle emission standards so you could spend more money at the pump and produce more greenhouse gas emissions, to create more of what you see around me — it’s beyond the pale of comprehension,” Newsom said. “We’re fighting against that and will prevail as long as more people come to this cause.”

The governor warned that the problems facing California and states along the West Coast would soon be experienced across the country.

“This is a climate damn emergency,” he said. “This is real and it’s happening.”

Newsom made a passionate argument for increasing efforts to address climate change as the number of acres that have burned in California so far this year topped 3 million and other state and foreign governments sent resources to battle major blazes statewide. 

Click here to access the entire article originally published on the Los Angeles Times website. 

With California ablaze, Newsom blasts Trump administration for failing to fight climate change by Taryn Luna, California, Los Angeles Times, Sep 11, 2020



Participating in Al Gore's Climate Reality Leadership Corps Training

Posted on 11 September 2020 by BaerbelW

It finally happened: about 13 years after first watching Al Gore’s documentary “An Inconvenient Truth” (AIT) in 2007 when it became available in Germany, I recently completed the Climate Reality Leadership Corps Training! Participating in this particular training had been on my to-do list for quite some time but it hadn’t worked out thus far for different reasons: I didn’t want to apply for one of the earlier trainings offered around the world as these would have meant having to fly there for a 3-day event which I didn’t want to do. Then, when an event was scheduled to happen in Berlin in 2018, it unfortunately didn’t work out timewise for me. However, due to COVID-19 the trainings were moved to an online format in 2020 and when I noticed, I immediately applied for the first virtual session planned to happen in July. Not too surprisingly, the training team got too many applications for the event (over 10,000!), so I ended up in the second round happening from August 28 to September 3.


The training was structured into five modules: Introduction, Science, Solutions, Social change, Skill building and “Taking it home”. Four live broadcast sessions featuring Al Gore giving his presentation divided into four parts made up the focal points. Each of these sessions was followed by additional shorter panel discussions and wrapped-up by live virtual “table discussions” under the guidance of a mentor with a group of 10 to 20 trainees. In addition, several on-demand sessions were available from which we had to at least watch four from a wide variety of topics. I picked sessions about “Ensuring a healthy future for all”, “Youth Leadership”, “Mastering the presentation” and “Engaging an Online Community”. Last but not least we also had to write “Our Climate Story” and about an example for impacts or solutions to climate change, ideally from our own neck of the woods. Here is the link to “My Climate Story”.



How to debunk misinformation

Posted on 10 September 2020 by John Cook

An effective rebuttal requires three elements. Fact. Myth. Fallacy. This video to explain how to tie these together into a cohesive debunking.



Skeptical Science New Research for Week #36, 2020

Posted on 9 September 2020 by doug_bostrom

Highlighted paper: Heat stored in the Earth system: where does the energy go?

A deep roster of familiar names in climate research headed by Karina von Schuckmann have just published an updated and for the first time comprehensive accounting of energy being stored in the Earth system due to radiative imbalance caused by greenhouse gases added to the atmosphere by "us truly." This is summarized as a single number called "Earth Energy Imbalance" (EEI), at slightly less than 0.5 Watts per square meter of Earth's surface. When penciled out it's an extremely large amount of energy in absolute terms. EEI  provides a simple handle for assessment of "how are we doing?" Schuckmann et al conclude that a reduction of CO2 in the atmosphere to 353 ppm (parts per million) from the present 410 ppm is a goal that will result in restoring an quasi-equilibrium state to the Earth's overall temperature, all other things being equal. A don't-miss publication, open access and free to read: Heat stored in the Earth system: where does the energy go?

Slight tweak to New Research

Articles in NR are categorized by domain, roughly. This introduces the problem of items that don't neatly fit in one slot, or that have significance in more than one discipline (happily becoming more frequent as the powerful multiplier of interdisciplinary cooperation is tapped more frequently). For that reason henceforth in some few cases we'll include an article in more than a single pigeonhole, in case particular readers are inclined to particular areas of interest.  

It remains the case that perfect categorization is an unsolved challenge; some findings defy categorization at the risk of landing in "Other."

96 Articles

Physical science of global warming & effects

Resolving inconsistencies in extreme precipitation‐temperature sensitivities

Re‐emergence of anthropogenic carbon into the ocean’s mixed layer strongly amplifies transient climate sensitivity

Elevation dependent warming over the Tibetan Plateau: Patterns, mechanisms and perspectives

Observations of global warming & effects

An increase in global trends of tropical cyclone translation speed since 1982 and its physical causes (open access)

Human contribution to the record-breaking June and July 2019 heatwaves in Western Europe



Pro Truth: A Pragmatic Plan to Put Truth Back Into Politics

Posted on 8 September 2020 by Guest Author

Guest post by Gleb Tsipursky

How do we get politicians to stop lying? How do we get private citizens to stop sharing fake news on social media? A new book, Pro Truth: A Pragmatic Plan to Put Truth Back Into Politics, provides an answer, documenting a new Pro Truth movement centered around the Pro-Truth Pledge.

We are facing a nightmare scenario. For many years now, traditional gatekeepers for ensuring the veracity of public information—news media, civic leaders, authorities on various topics—have been trusted less and less. Social and digital media have only accelerated this trend, exemplifying the potential of technological disruption to undermine our democracy.

Fortunately, if we can create a mechanism that differentiates the liars from the truth-tellers, we have a hope of protecting our democracy. At the same time, tilting the scale toward truth requires addressing the psychological factors that cause people to tolerate untruths. Using research from behavioral science research about what causes people to lie and what motivates them to tell the truth, a number of behavioral scientists (including myself) and concerned citizens have launched the Pro-Truth Pledge at, which combines our knowledge of behavioral science with crowdsourcing to promote truth-oriented behavior. The pledge is the tip of the iceberg of a broader Pro Truth movement described in the book.

The pledge is meant for both public figures and organizations, as well as for private citizens, such as you, dear reader. In fact, many thousands of private citizens across the globe have signed the pledge. So have over 800 politicians (including 4 members of the US Congress, over 50 state legislators, and 3 former US Democratic Presidential candidates); over 200 organizations (including Skeptical Science, Stand Up Republic, Media Bias Fact Check, and United Coalition of Reason); and over 1,000 other public figures (including globally-known public intellectuals such as Jonathan Haidt, Steven Pinker, Peter Singer, Chip Heath, and Michael Shermer).

The Pro-Truth Pledge incorporates 12 countermeasures to the psychological factors that foster misinformation. Signers pledge their earnest efforts to make it a practice to:



Five science questions to be asked at the debates

Posted on 7 September 2020 by Guest Author

This is a re-post from Yale Climate Connections by Gary Yohe, Henry Jacoby, Ben Santer, and Richard Richels

Three debates between the presidential candidates and one between the vice presidential candidates are scheduled before Americans vote for the next U.S. President on November 3.

In past elections, debates have largely ignored issues like climate change and global pandemics. This year, it’s likely to be a different story. Americans want to know how the next President of the United States intends to protect them from the twin scourges of climate disruption and COVID-19. How well do the candidates understand these issues? Is their understanding grounded in science or in wishful thinking? What are their plans for responding to the relentless warming of the planet, and to a virus that has already taken more than 185,000 American lives, with many more coming?

This year’s debates might be more informative if moderators and questioners begin to prepare such questions now. Let’s phrase them carefully, think about what the candidates might say in response, and craft follow-ups. The goal is simple – to bring into the open real differences in the candidates’ understandings, positions, and policies. Let’s expose the bright dividing lines on these important issues, while avoiding “gotcha” questions that generate more heat than light.

Here we offer a short list of sample questions on issues related to climate, the environment, public health, and the value of science. Each question comes with a few sentences to add context and possible follow-up questions.


Context: The United States has historically been a leader in international efforts to solve global problems like climate change, arms control, and infectious diseases. Some express concern that we have in many ways given up that role.

Question: Please give an example of a global science-based issue of such importance that you would give it your time and personal capital as president.

Follow-up: How would you organize, lead, and promote international collaboration in confronting the issue you identified?



2020 SkS Weekly Climate Change & Global Warming Digest #36

Posted on 6 September 2020 by John Hartz

Story of the Week... Toon of the Week... Photo of the Week... Coming Soon on SkS... Poster of the Week... SkS Week in Review...

Story of the Week...

Massive mystery holes appear in Siberian tundra — and could be linked to climate change

Inspection of tundra crater in Siberia Aug 2020

In August 2020, the RAS Institute of Oil and Gas Problems, supported by the local Yamal authorities, conducted a major expedition to the new crater. Skoltech researchers were part of the final stages of that expedition. Credit: Evgeny Chuvilin

A Russian TV crew flying over the Siberian tundra this summer spotted a massive crater 30 meters (100 feet) deep and 20 meters wide — striking in its size, symmetry and the explosive force of nature that it must have taken to have created it.

Scientists are not sure exactly how the huge hole, which is at least the ninth spotted in the region since 2013, formed. Initial theories floated when the first crater was discovered near an oil and gas field in the Yamal Peninsula in northwest Siberia included a meteorite impact, a UFO landing and the collapse of a secret underground military storage facility.

While scientists now believe the giant hole is linked to an explosive buildup of methane gas — which could be an unsettling result of warming temperatures in the region — there is still a lot the researchers don't know.

Click here to access the entire article originally posted on the CNN website. 

Massive mystery holes appear in Siberian tundra — and could be linked to climate change by Katie Hunt, CNN, Sep 4, 2020



2020 SkS Weekly Climate Change & Global Warming News Roundup #36

Posted on 5 September 2020 by John Hartz

A chronological listing of news articles linked to on the Skeptical Science Facebook Page during the past week: Sun, Aug 30, 2020 through Sat, Sep 5, 2020

Editor's Choice

Biden’s Early Climate Focus and Hard Years in Congress Forged His $2 Trillion Clean Energy Plan

The Democratic nominee has called the Green New Deal a 'crucial framework' for the nation’s future, but he does not support calls for a fracking ban.

Joe Biden 

Former vice-president Joe Biden accepts the Democratic Party nomination for president during the last day of the Democratic National Convention, being held virtually amid the novel coronavirus pandemic, at the Chase Center in Wilmington, Delaware on Aug. 20, 2020. Credit: Olivier Douliery/AFP via Getty Images 

Former Vice President Joe Biden's long political career spans the early days of hope for U.S. climate action, and the present days of alarm.

He sponsored one of the first pieces of climate legislation in Congress, a benign proposal to study the greenhouse effect that met enough resistance to signal the hard fight ahead.

More than 30 years later, as the Democratic nominee for president, Biden is seeking to seize what many see as the last opportunity for the U.S. to stave off catastrophe.

Biden's instinct, as embodied in the climate plan he unveiled early in this presidential run, is for moderation. He'd rather regulate than ban. He favors incentives, not force.

But as fire scorched the West and tropical storms doused the East in what science says is only a harbinger of things to come, amid passionate pleas of young activists who fear for their future, and in the face of President Donald Trump's abandonment of U.S. responsibility to act, Biden has jettisoned half-measures.

"We're not just going to tinker around the edges," Biden said in announcing his expanded $2 trillion clean energy transformation plan in July.

Click here to acces the entire article originally posted on the InsideClimate News website.  

Biden’s Early Climate Focus and Hard Years in Congress Forged His $2 Trillion Clean Energy Plan by Marianne Lavelle, InsideClimate News, Aug 31, 2020



The story of climate consensus

Posted on 2 September 2020 by John Cook

The scientific consensus on human-caused global warming has been a fierce topic for decades. To understand why, you need to know the history of consensus. The first message the public heard about the consensus on climate change was that there was no consensus. Next, scientists published a series of studies quantifying expert agreement on human-caused global warming – multiple studies found 90 to 100% agreement with multiple studies converging on 97% consensus. In response, climate deniers continued to argue there was no consensus (as well as argue scientists should stop talking about it because science isn’t done by consensus).



Skeptical Science New Research for Week #35, 2020

Posted on 2 September 2020 by doug_bostrom

121 Articles

Physical science of global warming & effects

Linearity of outgoing longwave radiation: From an atmospheric column to global climate models

Observations of global warming & effects

Antarctic Bottom Water Warming in the Brazil Basin: 1990s through 2020, from WOCE to Deep Argo

Rapid worldwide growth of glacial lakes since 1990

Ice-sheet losses track high-end sea-level rise projections

Trends and spatial variation in rain-on-snow events over the Arctic Ocean during the early melt season (open access)

Recent changes in heatwave characteristics over Korea

Roles of sea surface temperature warming and loss of Arctic sea ice in the enhanced summer wetting trend over northeastern Siberia during recent decades

Climate change drives increases in extreme events for lake ice in the Northern Hemisphere

Decline in Temperature Variability on Svalbard

The temperature increase in Greenland has accelerated in the past five years

Aridity trends in the Middle East and adjacent areas

Changing Spatio‐Temporal Trends of Heat Wave and Severe Heat Wave Events over India: An emerging health hazard

Different changes in dry and humid heat waves over China

Climatology and trends of reference evapotranspiration in Spain

Secular trend of global drought since 1950



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