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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?


2021 SkS Weekly Climate Change & Global Warming News Roundup #20

Posted on 16 May 2021 by BaerbelW

Listing of articles linked to on the Skeptical Science Facebook Page during the past week: Sun, May 9, 2021 through Sat, May 15, 2021

This week we seeded our Facebook queue well ahead of time to work around some organisational bottleneck. Which is why we mostly "Revisited some Analogies" and shared recently published Repustar Fact Briefs throughout the week. The article inspiring most activities not just this week but for the last several weeks was Revisiting some Analogies - Arctic ice, sailboat keels, and wild weather. It garnered a lot more impressions, comments, shares and likes than most other recently published articles. From what we can tell, especially the revisited analogies written by Evan and jg were very well received throughout the week. Please let us know what you thought about running posts as a series like we did last week. If there's interest we might do it again sometime in the future.

Articles Linked to on Facebook



China’s 2060 climate pledge is ‘largely consistent’ with 1.5C goal, study finds

Posted on 14 May 2021 by Guest Author

This is a re-post from Carbon Brief by Xiaoying You

New research has found that China’s pledge to achieve “carbon neutrality” before 2060 is “largely consistent” with the Paris Agreement’s aim of limiting global warming to 1.5C. 

But, to stay below this level of warming, the country will need to aim higher than its current net-zero goal and accomplish “deep” emission reductions in the near term, the authors state.

According to the study, to hit the 1.5C goal, the world’s largest emitter would need to cut its total carbon dioxide (CO2) emissions and energy consumption by more than 90% and 39%, respectively, by 2050 – compared to a “no-policy” scenario where the government has not and will not impose climate policies.

The paper, published in Science, also finds that the 1.5C mark would require China’s fossil fuel consumption to be “dramatically reduced” and demand for coal to drop to nearly zero by 2050.

Dr Hongbo Duan, the lead author, says the study “fills a gap” because no previous research had focused on assessing the efforts required by China to contribute to the 1.5C ambition of Paris.



Skeptical Science New Research for Week #19, 2021

Posted on 12 May 2021 by doug_bostrom

Putting a price tag on upcoming atmospheric rivers

The Clausius-Clapeyron equation isn't complicated— once somebody has thought of the concept and mathematically tamed it. However,  the deceptively meek and harmless looking caged expression of the idea in combination with an entire planet's atmosphere heating up in the presence of an ample water supply unpacks as a zoo of forbidding complications for us humans and our built environment.

Capturing and quantitatively describing details of how our climate train wreck is going to unfold is in some ways even more difficult than establishing root cause principles such as the Clausius-Clapeyron.equation. A lot of previous work in disparate disciplines has first to be assembled and then extended into an self-consistent, coherent whole in order to produce useful results, with this work requiring objectively remarkable aggregations of specialist insight working in deep cooperation. Despite the steep hill of progress, researchers with sufficient collective technical and collaborative skills and employing newly available tools are elucidating consequences of our fundamental error in fixating on fossil hydrocarbons as our principal energy source.

In this week's highlighted article and exemplar of what might be termed "reverse engineering the future" we learn details about how water already available will interact with heat we're accidentally providing to cost us a lot of inconvenience, along with eye-popping amounts of money. Rhoades et al marry the physical science and modeling of climate change with large-scale economic damage exposure and loss to explore and quantify one such inexorably damper and warmer scenario in Implications of warming on western United States landfalling atmospheric rivers and their flood damages.  The paper essentially hinges on this seemingly bland statement of basic facts:

Feedbacks that alter thermodynamic processes arise primarily from the Clausius-Clapeyron relationship (i.e., column-integrated water vapor increases at approximately +7.5%/K [17]) that in turn influences the magnitude and variability of moisture sources that seed ARs.

A short sentence that mushrooms when fully teased out, quantified and put into the context of human affairs. These investigators have obviously put a lot of effort into this publication but the takeaway for us laypersons is not very complicated: a "successful" confinement of temperature rise to 2 degrees C will leave the West Coast of the US with an annual $2 billion additional bill for flood damages. This is due to the ratio of beneficial to damaging atmospheric rivers being substantially changed. From the abstract: 

We show that warming increases the number of water manage-ment relevant landfalling ARs from 19.1 ARs per year at +0?C to 23.6 ARs per year at +3?C. Additionally, this warming intensifies the amount of wa-ter transported by landfalling ARs resulting in a decrease in the fraction of ARs that are “mostly to primarily beneficial” to water resource management (i.e., 91% of ARs at +0?C to 78% at +3?C) and an increase in the fraction of ARs that are “mostly or primarily hazardous” to water resource manage-ment (i.e., 2% of ARs at +0?C to 8% at +3?C). 

Implications of warming on western United States landfalling atmospheric rivers and their flood damages is open access and despite being "free" is possibly worth quite a few billion dollars— if we read and hear.

Circling back to the Enlightenment?

Notable: over 1/2 of this edition's articles are open access, the first such ratio of quantified scientific integrity since we've been keeping track. Could the apparatus of scientific publishing be shedding its recently adopted Rupert Maxwell architecture, moving beyond its oddly anachronistic alchemy-inspired phase? Are we seeing a secular trend? Don't jinx the graph by making predictions. 

99 articles

Observations of climate change, effects

An assessment of climate change impact on air masses arriving in Athens, Greece
Karozis et al 2021 Theoretical and Applied Climatology
DOI: 10.1007/s00704-021-03624-x

Regional differences in surface air temperature changing patterns from 1960 to 2016 of China
Yuan et al 2021 Climate Dynamics
DOI: 10.1007/s00382-021-05774-0

Climate change and Northern Hemisphere lake and river ice phenology from 1931–2005
Newton & Mullan 2021 The Cryosphere
Open Access pdf DOI: 10.5194/tc-15-2211-2021

Ice-marginal lakes associated with enhanced recession of the Greenland Ice Sheet
Mallalieu et al 2021 Global and Planetary Change
DOI: 10.1016/j.gloplacha.2021.103503

Heat waves in spring from Senegal to Sahel: Evolution under climate change
Sambou et al 2021 International Journal of Climatology
DOI: 10.1002/joc.7176

First and last frost date determinations based on meteorological observations in Japan: trend analysis and estimation scheme construction
Masaki 2021 Theoretical and Applied Climatology
DOI: 10.1007/s00704-021-03637-6

Prolonged Siberian heat of 2020 almost impossible without human influence
Ciavarella et al 2021 Climatic Change
Open Access pdf DOI: 10.1007/s10584-021-03052-w

Instrumentation & observational methods of climate change, effects



How sure are climate scientists?

Posted on 11 May 2021 by BaerbelW

We were recently made aware of a new video created by Neil Halloran called "Degrees of Uncertainty" which is an animated documentary about climate science, uncertainty, and knowing when to trust the experts. Watch it on YouTube (24 minutes):

Neil credits several climate scientists at the end of his video and one of them, Zeke Hausfather, had this to say about the video on Twitter (click for larger version):


Degrees of Uncertainty features four moments of interactivity that are only available when viewing the film on Neil's homepage. When the option is presented, simply pause the video to activate an "interactive mode" featuring clickable content:



Overshooting 2C risks rapid and unstoppable sea level rise from Antarctica

Posted on 10 May 2021 by Guest Author

This is a re-post from Carbon Brief by:

Dr Robert M. DeConto, professor of geosciences and co-director of the School of Earth and Sustainability at the University of Massachusetts-Amherst, lead author on IPCC’s special report on the ocean and cryosphere in a changing climate, and a recipient of the Tinker-Muse Prize for Science and Policy in Antarctica.

Pamela Pearson, director of the International Cryosphere Climate Initiative, a former US diplomat (1987-2006) and climate, health and environment negotiator.

Dr David Pollard, research professor emeritus at Pennsylvania State University and fellow of the American Geophysical Union.

In 2015, governments from across the world committed to the Paris Agreement and its goal of limiting global warming to 1.5C or 2C. Yet, the emissions pledges that those governments have since proposed put the world on course for as much as 3C of warming.

Such a mismatch between ambition and action could have huge ramifications for the world, not least for global sea level rise, which is already accelerating.

In a new modelling study, published in Nature, we show what the difference between meeting the Paris goals and overshooting them could mean for the melting ice of Antarctica.

At 1.5C or 2C, we find that Antarctic ice melt continues at similar levels as today – albeit a contribution that would continue for centuries.

However, at 3C, we find significant risks of rapid, irreversible sea level rise before 2100. Our model incorporates glaciological processes observed over the past several decades, including the impact of ice shelf loss on outlet glaciers and subsequent marine-based “ice cliff” collapse.

We also show that our model is able to accurately reproduce sea level changes in Earth’s ancient past, which increases confidence that they can simulate long-term impacts beyond 2100. Significantly, our model demonstrates threshold behaviour once warming passes 2C, revealing the risks of overshooting the Paris goal and the apparent limits of carbon removal to halt these processes once they have started.



2021 SkS Weekly Climate Change & Global Warming News Roundup #19

Posted on 9 May 2021 by BaerbelW

Listing of articles linked to on the Skeptical Science Facebook Page during the past week: Sun, May 2, 2021 through Sat, May 8, 2021

In no particular order the following articles lead to the most interactions during the last seven days: Shifting Distribution of Land Temperature Anomalies, 1951-2020, Dare we hope? Here’s my cautious case for climate optimism, Biden's first 100 days: Where he stands on science, How sure are climate scientists? | Degrees of UncertaintyChina’s carbon pollution now surpasses all developed countries combined and The conventional wisdom on how to talk about climate change? It’s wrong.

Articles Linked to on Facebook



Explainer: Will global warming ‘stop’ as soon as net-zero emissions are reached?

Posted on 6 May 2021 by Zeke Hausfather

This is a re-post from Carbon Brief

Media reports frequently claim that the world is facing “committed warming” in the future as a result of past emissions, meaning higher temperatures are “locked in”, “in the pipeline” or “inevitable”, regardless of the choices society takes today.

The best available evidence shows that, on the contrary, warming is likely to more or less stop once carbon dioxide (CO2) emissions reach zero, meaning humans have the power to choose their climate future.

When scientists have pointed this out recently, it has been reported as a new scientific finding. However, the scientific community has recognised that zero CO2 emissions likely implied flat future temperatures since at least 2008. The Intergovernmental Panel on Climate Change (IPCC) 2018 special report on 1.5C also included a specific focus on zero-emissions scenarios with similar findings. 

Much of the confusion around committed warming stems from mixing up two different concepts: a world where CO2 levels in the atmosphere remain at current levels; and a world where emissions reach net-zero and concentrations begin to fall.

Even in a world of zero CO2 emissions, however, there are large remaining uncertainties associated with what happens to non-CO2 greenhouse gases (GHGs), such as methane and nitrous oxide, emissions of sulphate aerosols that cool the planet and longer-term feedback processes and natural variability in the climate system. 

Moreover, temperatures are expected to remain steady rather than dropping for a few centuries after emissions reach zero, meaning that the climate change that has already occurred will be difficult to reverse in the absence of large-scale net negative emissions.



Skeptical Science New Research for Week #18, 2021

Posted on 5 May 2021 by doug_bostrom

Bringing more certainty to uncertainty communications

For the armchair dilettante observer of scientific progress a solid literature review is something akin to going to Disneyland. It's almost too much stimulation. When a review covers a salient, hot topic, so much the better. More seriously, literature reviews are an opportunity for a scientific community to "take stock," identify where commonality of purpose might benefit and where gaps or discontinuities in knowledge are stubbornly lodged or newly developing. For the layperson, a review is a great way to gain a toehold on current understanding.

This week we're pleased to feature a vast review focusing on a key factor controlling public thinking and hence policy progress toward remedying our unfortunate, accidental launching of rapid climate change. "Communications about uncertainty in scientific climate-related findings: a qualitative systematic review" by Astrid Kause et al provides a sweeping view of our best understanding of how people are dealing with the notion of uncertainty when thinking about climate, and how future research might best be directed. 

From the review, it's safe to say there's a lot of work left to be done in this arena; research into public thinking about uncertainty and climate change might be termed as in the "generating more questions" as opposed to "answering questions" phase.  As well, this field of inquiry affords what might be termed an embarrassment of riches in terms of suggestive, tentative findings begging for followup. Finally, there's a lack of coordination or normalization around much of the mechanical aspect of this research work as practiced, such that forming "big picture" conclusions is somewhat stymied. 

Our understanding of uncertainty underpins our thinking about hazards and risks, in the face of what we know are very poor native cognitive skills in producing useful answers when confronted with this trio of probabilistic challenges. Subpar thinking skills in this department lead to bad decisions. Given the need for informed public engagement to drive political energy and - ultimately - useful policy formulation, we face a strong imperative to cement our understanding of and skill in helping the public to accurately perceive and productively think about uncertainty as it concerns climate change. Kause et al is open access, free to read, a diligently constructed snapshot of our present understanding of these matters. From the abstract:

We find that studies of communications about uncertainty in scientific climate-related findings substantially varied in how they operationalized uncertainty, as well as how they measured responses. Studies mostly focused on uncertainty stemming from conflicting information, such as diverging model estimates or experts, or from expressions of imprecision such as ranges. Among other things, users' understanding was improved when climate communications about uncertainty in scientific climate-related findings were presented with explanations about why climate information was uncertain, and when ranges were presented with lower and upper numerical bounds. Users' understanding also improved if they expressed stronger beliefs about climate change, or had better numerical skills. Based on these findings, we provide emerging recommendations on how to best present communications about uncertainty in scientific climate-related findings; and we identify research gaps.

126 Articles

 Physical science of climate change, effects

Early-onset of Atlantic Meridional Overturning Circulation weakening in response to atmospheric CO2 concentration
Dima et al 2021 npj Climate and Atmospheric Science
Open Access pdf DOI: 10.1038/s41612-021-00182-x



#PLURV - the German #FLICC - getting popular in Germany

Posted on 4 May 2021 by BaerbelW

Longtime readers of what we are up to at Skeptical Science will be well aware of the FLICC taxonomy first suggested by Mark Hoofnagle in 2007, written about in Diethelm & McKnee (2009) and since then greatly enlarged by John Cook:


A much simpler FLICC-taxonomy first started out to be utilized in our MOOC Denial101x where it was used to explain and highlight the techniques used to distort the findings of climate science research. But even then it was pretty clear, that taking this kind of approach could be applied not just to climate science but to many other (science) areas. Right from the start of our MOOC we've had a section in our discussion forums asking the students to come up with FLICC-examples from other areas.



Report: All new cars and trucks in U.S. could be electric by 2035

Posted on 3 May 2021 by Bud Ward

This is a re-post from Yale Climate Connections

Thinking ahead to what (and whether?) you may be driving – may have parked in your garage or driveway or parking lot – a few years from now? Like, for instance, in 2035?

Only with “robust” public policy initiatives as yet not on the books (and perhaps not even on the horizon?), could you find yourself choosing, whether a new passenger car or truck, from among only all-electric vehicles? That’s the case if the findings of a newly released analysis from the University of California, Berkeley, and colleagues are to be believed.

The new reports, by Berkeley scholars and colleagues from the nonprofit group Energy Innovation, find (spoiler alert here: big caveat coming) that with “the right policy” across a number of areas, “all new cars and trucks sold in the United States can be powered by electricity by 2035.” Minus those policy adjustments, the researchers warn, “most of the potential to reduce emissions, cut transportation costs, and increase jobs will not be realized.”

(The sweeping studies described in this piece were made public just prior to news reports that the Biden administration was about to commit to reducing greenhouse gas emissions by about 50% by just the end of this decade, requiring “profound changes at home,” the Washington Post reported.)

Technical and economic hurdles are ‘challenging but achievable’

“Political will, policy, and consumer acceptance – not technical or economic feasibility – are the largest barriers” to be overcome, the report authors write at one point.

In what must seem a blanket endorsement of EV proponents, they say their analyses demonstrate that improved battery technology, costs, manufacturing scale, and industry ambition will accelerate rapid electrification of cars and trucks. And they are not awed by the need to build the extensive battery charging infrastructure needed to support a transition to electric vehicles: All that infrastructure “can be built quickly and cost-effectively,” they write: “The pace of the required infrastructure scale-up is challenging but achievable, and the costs are modest compared with the benefits of widespread EV deployment.”



2021 SkS Weekly Climate Change & Global Warming News Roundup #18

Posted on 2 May 2021 by BaerbelW

Listing of articles linked to on the Skeptical Science Facebook Page during the past week: Sun, Apr 25, 2021 through Sat, May 1, 2021

In no particular order the following articles lead to the most interactions during the last seven days: Points of no return, What Skepticism Reveals About Science, The Origin Story Of GOP Outrage Over Totally Imaginary Biden Red Meat Ban, Don’t ask officials what they think of global warming — ask if they want a warning, Nestlé threatened with cease-and-desist over alleged illegal water use and Explainer: Will global warming ‘stop’ as soon as net-zero emissions are reached?.

Articles Linked to on Facebook



Skeptical Science collaborates with Repustar to provide Fact Briefs

Posted on 29 April 2021 by John Cook, BaerbelW

We were recently put in touch with Repustar’s founder and CEO Chandran Sankaran, interested in collaborating with Skeptical Science to create climate-related Fact Briefs for their platform. As a new startup, Repustar describe their approach on their About Us page:

Repustar enables everyone to support their conversations online with facts from credible sources. Organizations that contribute to the platform look into the public’s concerns and respond with clear answers supported by credible data and documents.

Repustar combines the tools of journalism and data science to allow well-sourced Fact Briefs to be discovered by the public when and where they are most needed.

News and research organizations with track records of nonpartisanship and evidence-based analyses can contribute their expertise to Fact Briefs, and the platform offers resources to professionals who analyze, create and distribute news.

With people everywhere disoriented about whom to believe and what to trust, Repustar seeks to enable a fact-forward world.

Repustar Fact Briefs

Their evidence-based approach was a good match for Skeptical Science and we began our collaboration with the first step of reviewing a few Fact Briefs drafted by the Repustar team based on some of our rebuttals. We are happy to announce that these initial Fact Briefs have now been published and that Skeptical Science is one of Repustar’s claims reviewing partners.

Repustar’s Fact Briefs are short and to the point, following a common structure where a closed question - answered by either “Yes” or “No” - is posed and answered with a short explanation. Here is an example of how that looks like for one of our Fact Briefs:

Repustar Example



Major parties’ climate programs are miles apart

Posted on 29 April 2021 by dana1981

This is a re-post from Yale Climate Connections

President Biden on Earth Day, April 22, unveiled America’s aggressive new climate target: a 50-52% reduction in greenhouse gas emissions below 2005 levels by 2030, on the way to the pledge of net zero emissions by 2050.

That ambitious target would deliver America’s contribution toward meeting the Paris Climate Agreement and the goal of limiting global warming to less than 2 degrees Celsius (3.6 degrees Fahrenheit) above pre-industrial temperatures. President Biden and supportive House Democrats are backing the pledge with a concrete legislative plan to rapidly curb greenhouse gas emissions. That said, important details of the administration’s legislative package remain largely unanswered, and it’s certain to face rough going when, in whatever eventual form, it gets to consideration in the narrowly divided Senate.

In an effort to show that they too care about climate change, House Republicans unveiled their “Energy Innovation Agenda” in the days preceding Biden’s Earth Day announcement. That agenda did not include any specific emissions targets. Rather, it includes a continued reliance on fossil fuels and explicitly opposes putting a price on carbon pollution. It stands in stark contrast to the Democrats’ ambitious plan to meet the Paris climate targets by transitioning to clean energy and leaving fossil fuels in the ground.

Democrats’ plan

House Democrats had been preparing for this moment. In the summer of 2020, the House Select Committee on the Climate Crisis released a comprehensive 547-page report detailing their plan, which analysts estimate would cut greenhouse gas emissions 40% below 2005 levels by 2030 and close to net zero by 2050.

To meet the Paris target of limiting global warming to less than 2°C, global greenhouse gas emissions must reach net zero by around the year 2075, depending on factors like the rate of pollution cuts and the amount of carbon removed from the atmosphere and sequestered underground. Wealthy nations like the U.S. will need to reach net zero emissions even sooner to allow developing countries more time to make the clean energy transition as their economies and energy needs grow. President Biden’s pledge is thus designed to hit a sweet spot: It’s about as fast as America theoretically can move, and fast enough to avert the worst climate consequences. Anything faster would be politically infeasible, but anything slower would be inconsistent with the Paris goals.

The House Democrats’ plan centers around fully decarbonizing the electric grid by 2040 (President Biden has been even more ambitious, calling for a zero-carbon grid by 2035) and electrifying as many other sectors as possible (think electric cars and trucks for transportation and electric heat pumps and appliances for buildings). To that end, the Biden administration and House Democrats have been working to include a clean electricity standard and $1 trillion in clean energy investments as part of their infrastructure legislation.

To pass these measures, the closely divided Senate may well need to try to proceed through the budget reconciliation approach requiring a bare majority 51-50 vote, which could likely require all 50 Senate Democrats to vote in favor, with Vice President Kamala Harris then breaking a tie.

In short, Democrats have an ambitious climate target and a blueprint to begin delivering on it. But there’s no certainty at this point on what specific legislative language can pass both the House and the Senate and earn the President’s signature for enactment.



vEGU21 - EOS7.10 - Science to Action

Posted on 28 April 2021 by BaerbelW

On Tuesday, April 27 2021 I participated in session EOS7.10 at the virtual General Assembly of the Eurogeosciences Union (EGU) titled Science to Action: Communication of Science and strategies to fight misinformation - Practice, Research and Reflection This session was convened by Sam Illingworth, Heidi Roop, Mathew Stiller-Reeve, Kristin Trimm, Laure Fallou, Irina Dallo, Michèle Marti and Femke Mulder. The session - run at both AGU and EGU - encouraged critical reflection on science communication best practices and provided an opportunity for the community of science communicators and researchers to share best practices and experiences with evaluation and research in this field. The session also explored the way efficient communication strategies can help prevent, fight and debunk misinformation. Case studies, comparisons between different hazards and risks as well as best practices to fight misinformation at all stages of the risk cycle were explored.

vEGU21 Lobby


There were so many interesting 2-minute pitches that it was impossible to just pick a handful to highlight in this blog post. Therefore, the table below shows thumbnails for the presentations I was able to capture a screenshot of and links to the details from there, basically a visual directory to the session. At the end of the blog post, I'll go into a bit more details on my own contribution to highlight resources Giving Facts a fighting chance against misinformation.

Please click on the presenting author's name to access the abstract and click on the thumbnail to open a larger version of the graphic.



Skeptical Science New Research for Week #17, 2021

Posted on 28 April 2021 by doug_bostrom

"CO2 is plant food." No.

Despite propaganda to the contrary CO2 isn't "plant food," any more than sugar is "food" for us humans. CO2 is a metabolic requirement for plants, an input among many to a complex metabolism evolved and tuned to work with what it "knows." Plants are adapted for less than 400 ppm of CO2 and when this level is exceeded strange effects can happen in terms of health and function of plants themselves. But it turns out that unexpected outcomes are even larger than we thought. In CO2 physiological effect can cause rainfall decrease as strong as large-scale deforestation in the Amazon, Gilvan Sampaio et al carefully work out a particularly non-obvious outcome: changes in plant metabolism due to increased CO2 in the air may cause knock-on effects on rainfall equal to that of large scale deforestation. Open access and free to read. From the abstract: 

Here, for the first time, we systematically compare the plant physiological effects of eCO2 and deforestation on Amazon rainfall. We use the CPTEC Brazilian Atmospheric Model (BAM) with dynamic vegetation under a 1.5×CO2 experiment and a 100 % substitution of the forest by pasture grasslands, with all other conditions held similar between the two scenarios. We find that both scenarios result in equivalent average annual rainfall reductions (Physiology: 257 mm, 12 %; Deforestation: 183 mm, 9 %) that are above the observed Amazon rainfall interannual variability of 5 %. The rainfall decreases predicted in the two scenarios are linked to a reduction of approximately 20 % in canopy transpiration but for different reasons: the eCO2-driven reduction of stomatal conductance drives the change in the Physiology experiment, and the smaller leaf area index of pasturelands (72 % compared to tropical forest) causes the result in the Deforestation experiment. The Walker circulation is modified in the two scenarios: in Physiology due to a humidity-enriched free troposphere with decreased deep convection due to the heightening of a drier and warmer (+2.1 ?C) boundary layer, and in Deforestation due to enhanced convection over the Andes and a subsidence branch over the eastern Amazon without considerable changes in temperature (0.2 ?C in 2 m air temperature and +0.4 ?C in surface temperature). But again, these changes occur through different mechanisms: strengthened west winds from the Pacific and reduced easterlies entering the basin affect the Physiology experiment, and strongly increased easterlies influence the result of the Deforestation experiment. 

Meteorologists: "Do keep up!"

A perspective piece in the Bulletin of the American Meteorological Society by Wright, Samara and Lopez-Cantu points out that even as we formulate adaptation and resilience policy and implementation details to account for changes in future weather and hydrology, the statistical ground on which those plans are being built is shifting beneath our feet and our plans will be found wanting if this isn't addressed. Resilience to Extreme Rainfall Starts with Science is open access and free to read. The abstract is succinct:

Intensification of extreme rainfall due to climate change means that federally published rainfall metrics such as the “100-yr storm” are outdated throughout much of the United States. Given their central role in a wide range of infrastructure designs and risk management decisions, updating these metrics to reflect recent and future changes is essential to protect communities. There have been considerable advances in recent years in data collection, statistical methods, and climate modeling that can now be brought to bear on the problem. Scientists must take a lead in this updating process, which should be open, inclusive, and leverage recent scientific advances.


For some reason, for this week our API calls to Unpaywall went unanswered with results in many cases. We're not sure what the problem may be— it appears to be on the other end of the line. Many articles that are open access are not shown as such in this week's edition, so if an item appeals, check it.

96 articles 

Physical science of climate change, effects

The Role of Atmospheric Feedbacks in Abrupt Winter Arctic Sea Ice Loss in Future Warming Scenarios
Hankel & Tziperman 2021 Journal of Climate
DOI: 10.1175/jcli-d-20-0558.1

Mechanism for the Spatial Pattern of the Amplitude Changes in Tropical Intraseasonal and Interannual Variability under Global Warming
Zhang et al 2021 Journal of Climate
DOI: 10.1175/jcli-d-20-0885.1

CO2 physiological effect can cause rainfall decrease as strong as large-scale deforestation in the Amazon



vEGU21 - EOS3.2 - Climate Literacy

Posted on 28 April 2021 by BaerbelW

A somewhat rocky start

On Monday, April 26 the 2nd week of vEGU21 - the all virtual General Assembly of the Eurogeosciences Union (EGU) - started into the scientific programs which were all held in the vPico format. The initial week had seen a much more relaxed schedule with mostly Great Debates, Union Symposia and Short Courses on the agenda. So, this start of the 2nd week saw a much increased pace, activities and attendees all rushing into the many online sessions running in parallel. So it was little wonder that many vPICO-sessions experienced some technical issues and that the conference servers were taxed to the max and sometimes even crashed under the load or were not reachable for a few minutes.

To get an idea of how the sessions worked - or were supposed to work - I had joined the Geoethics session EOS4.2 which turned out to be one of those affected by these issues. The conveners Silvia Peppoloni and Giuseppe Di Capua did an amazing job to nonetheless get through all the presentations in the allocated time but unfortunately the text-chat break outs didn't come to pass. As other sessions had comparable issues, a decision was made by the organizers to switch from Big Blue Button to Zoom as the session tool and during a longer than planned lunch-break all afternoon sessions received a Zoom-ID and could get underway an hour later than originally planned. The EGU Today Newsletter for Tuesday, April 27 has some more information about the rocky start and recovery from that.

EOS3.2 - Climate Literacy


Clockwise from top left: Climate literacy logo designed by Robin Matthews; Using foods we love and need to enhance climate literacy by Michael Hoffmann; Getting to impact at scale by Juliette Rooney-Varga and Florian Kapmaier; Rising To The Challenge by Emer Emily Neenan; Resources for teachers on the “Ocean and Cryosphere in a Changing Climate”  by Simon Klein et al.; Developing Climate Change Literacy to Combat Climate Change and Its Impacts by Julie Johnston



Skeptical about a defense of science?

Posted on 26 April 2021 by doug_bostrom

On April 21 US House Representative Frank Lucas (3rd District, Oklahoma)  transmitted an urgent inquiry to the White House concerning the abrupt reassignment of Dr. Betsy Weatherhead, out of her position as head of the Fifth United States Climate Assessment and into another role at the United States Geological Survey. Rep. Lucas expressed dismay with this decision while asking for background information, writing: "While Administrations are free to hire their own political appointees, penalizing and removing civil servants represents disturbing political interference in the federal scientific enterprise." He went on to express that it was "difficult to think of a more clear example of political interference and bias than this leadership change."

Representative Lucas' claims and complaints are puzzling in light of his personal context of career, experience and habits of attention.

Representative Lucas assumed office in 2003, and as with the rest of us has just emerged from a period of interference in the scientific activities conducted by the federal government unequaled in modern history and arguably during any period since congress and the executive branch first began integration of science into the apparatus of national government. This meddling significantly degraded scientific capacities and capabilities intended to help improve the lives of US citizens. The previous administration's tampering was breathtaking in its sweeping scope and brazen nature, widely publicized, impossible to ignore. Mr. Lucas was a member of the House Committee on Science, Space and Technology while this maelstrom swept over the federal scientific enterprise, on watch.

By his office, by his party affiliation, and by his deep experience with affairs and practices of the federal government Mr. Lucas was ideally positioned to monitor the rough handling of scientific integrity during a period of exceptionally transgressive actions. Thanks to the efforts of previous administrations, protection of scientific integrity within federal departments and agencies is a formally recognized, codified priority throughout the federal government. The performance of the government in respect of this is monitored both within the government and by independent organizations.  Representative Lucas has enjoyed continuous, easy access to multiple channels of surveillance of scientific integrity prior to April 21. 

Graph: Tallies of assaults on functions and integrity of federal government scientific endeavor during first two years of previous administration, unnoticed by Representative Lucas. Source: Union of Concerned Scientists



2021 SkS Weekly Climate Change & Global Warming News Roundup #17

Posted on 25 April 2021 by BaerbelW

Listing of articles linked to on the Skeptical Science Facebook Page during the past week: Sun, Apr 18, 2021 through Sat, Apr 24, 2021

In no particular order the following articles lead to the most interactions during the last seven days: The Campaign Against the Climate: Debunking climate change denial, The Science of Climate Change Explained: Facts, Evidence and Proof, Special Report-He was one of the first to warn us the world was getting hotter, Why scientists shouldn't heed calls to 'stay in our lane'and Despite Hate From Evangelicals, Katharine Hayhoe Sees Climate Hope.

Articles Linked to on Facebook



SkS Analogy 22 - Energy SeaSaw

Posted on 22 April 2021 by Evan, jg

Tag Line

Energy exchange vs. Energy change.

Elevator Statement

Energy change represents a change of the total global energy. Energy exchange represents an exchange of energy between two parts of the Earth’s systems, without necessarily increasing the total energy.

A seesaw exchanges the potential energy of Person A on one side of the seesaw to Person B on the other side of the seesaw. As Person A falls, they lose potential energy, causing Person B to rise, gaining the potential energy lost by Person A. In this process there is no change in the total energy of Person A+B: energy is merely exchanged between two people (there is a small amount of energy lost due to friction in the center pivot, requiring each person to push off the ground a small amount).


Climate Science

The oceans and the atmosphere represent two objects that also exchange energy, engaging in their own SeaSaw, where in some years the oceans lose energy to the atmosphere, and in other years the atmosphere loses energy back to the oceans. Just as two people using a seesaw merely exchange potential energy back and forth, without changing their total potential energy, so too, during energy SeaSaw cycles the oceans and atmosphere exchange energy. Although the long-term trend is that global warming causes both the oceans and the atmosphere to gain energy, because the energy exchanged between the oceans and the atmosphere can be up to 10 times as much as the energy gained by the atmosphere during a given year, it is usually difficult to estimate the amount of global warming from the temperature change of the atmosphere from one year to the next. To estimate the magnitude of global warming typically requires looking at atmospheric temperature trends from one decade to the next, or more commonly, by using a 10-year moving average. Try out the SkS Temperature Trend Calculator to see how the averaging period affects the temperature trend line.



Skeptical Science New Research for Week #16, 2021

Posted on 21 April 2021 by doug_bostrom

Near doubling of age of oldest coherent ice core on tap?

Studies of paleoclimate  help us to understand our own recent creation of accidental rapid climate change and what we may expect from our blunder. Among many other sources of paleoclimate data, ice cores stand out for their near "tape recorder" fidelity in recording various features of climate of the past and - even better - some direct information about what may have been shaping climate at any given time during ice core coverage.

The very oldest ice recovered from "deep storage" in Antarctica  (and anywhere) so far dates back about 2.7 million years. There is certainly useful information to be had from these samples but as a tape recording goes they're the equivalent of a reel that has been sliced into segments of instants of time then scrambled, with most segments gone missing. That's because their preservation was the result of happenstance as ice passing over particular forms of topography encountered "turbulence," with some  fragments of very old layers pushed higher toward the surface so that even while parent layers were subsequently lost, these scattered parts remained available. Beyond this fluky preservation mechanism leaving a lot of gaps, it's a non-trivial job to identify the age of such chunks and unscramble their place in chronology.

The oldest coherent and most-like-a-tape-recording ice core we have in hand spans a bit more than 800,000 years into the past. This is an impressive achievement and has proven valuable for our understanding of climate behavior and drivers over "deep time." But of course it leaves us hungry for more, according with our species' insatiable curiosity.

Now a substantial team of researchers led by David Lilien have published a paper that may well mark exactly "X" on the map of where to drill in order to nearly double our coherent ice core record. Yet again the spot lies in Antarctica. Using newly available radar equipment and an abundance of brain power, the group have identified and characterized an apparently intact sequence of ice layers extending to 1.5 million years ago. This is an important, significant discovery. These results suggest it won't be long before we see cores hauled up; the prospects and demand for new data are compelling to "drill, baby, drill." When those cores emerge, our insight into climate behavior will be projected backward to nearly double what we could before see.

New radar constraints support presence of ice older than 1.5 Myr at Little Dome C is open access and free to read. The abstract:

The area near Dome C, East Antarctica, is thought to be one of the most promising targets for recovering a continuous ice-core record spanning more than a million years. The European Beyond EPICA consortium has selected Little Dome C (LDC), an area  35 km southeast of Concordia Station, to attempt to recover such a record. Here, we present the results of the final ice-penetrating radar survey used to refine the exact drill site. These data were acquired during the 2019–2020 austral summer using a new, multi-channel high-resolution very high frequency (VHF) radar operating in the frequency range of 170–230 MHz. This new instrument is able to detect reflectors in the near-basal region, where previous surveys were largely unable to detect horizons. The radar stratigraphy is used to transfer the timescale of the EPICA Dome C ice core (EDC) to the area of Little Dome C, using radar isochrones dating back past 600 ka. We use these data to derive the expected depth–age relationship through the ice column at the now-chosen drill site, termed BELDC (Beyond EPICA LDC). These new data indicate that the ice at BELDC is considerably older than that at EDC at the same depth and that there is about 375 m of ice older than 600 kyr at BELDC. Stratigraphy is well preserved to 2565 m,  93 % of the ice thickness, below which there is a basal unit with unknown properties. An ice-flow model tuned to the isochrones suggests ages likely reach 1.5 Myr near 2500 m,  65 m above the basal unit and  265 m above the bed, with sufficient resolution (19 ± 2 kyr m−1) to resolve 41 kyr glacial cycles.

54 Articles 

Observations of climate change, effects

Homogenization and trends analysis of the Belgian historical precipitation time series
Bertrand et al 2021 International Journal of Climatology
DOI: 10.1002/joc.7129

Unprecedented drought in South India and recent water scarcity
Mishra et al 2021 Environmental Research Letters
Open Access DOI: 10.1088/1748-9326/abf289

A committed fourfold increase in ocean oxygen loss
Oschlies & Oschlies 2020
Open Access pdf DOI: 10.1038/s41467-021-22584-4

Warming amplification over the Arctic Pole and Third Pole: Trends, mechanisms and consequences
You et al 2021 Earth-Science Reviews
DOI: 10.1016/j.earscirev.2021.103625

Multi-decadal (1953–2017) rock glacier morphodynamics analysed by high-resolution topographic data in the Upper Kauner Valley, Austria
Fleischer et al 2021
Open Access pdf DOI: 10.5194/tc-2021-77

Widespread decline in winds delayed autumn foliar senescence over high latitudes
Wu et al 2021 Proceedings of the National Academy of Sciences
DOI: 10.1073/pnas.2015821118

Intense extreme hydro-climatic events take a toll on society
Bozorg-Haddad et al 2021 Natural Hazards
DOI: 10.1007/s11069-021-04749-y



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