Climate Science Glossary

Term Lookup

Enter a term in the search box to find its definition.


Use the controls in the far right panel to increase or decrease the number of terms automatically displayed (or to completely turn that feature off).

Term Lookup


All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

Home Arguments Software Resources Comments The Consensus Project Translations About Support

Twitter Facebook YouTube Pinterest MeWe

RSS Posts RSS Comments Email Subscribe

Climate's changed before
It's the sun
It's not bad
There is no consensus
It's cooling
Models are unreliable
Temp record is unreliable
Animals and plants can adapt
It hasn't warmed since 1998
Antarctica is gaining ice
View All Arguments...

New? Register here
Forgot your password?

Latest Posts


Explaining climate change science & rebutting global warming misinformation

Global warming is real and human-caused. It is leading to large-scale climate change. Under the guise of climate "skepticism", the public is bombarded with misinformation that casts doubt on the reality of human-caused global warming. This website gets skeptical about global warming "skepticism".

Our mission is simple: debunk climate misinformation by presenting peer-reviewed science and explaining the techniques of science denial.


Is cost-benefit analysis the right tool for federal climate policy?

Posted on 25 October 2021 by Guest Author

This is a re-post from Yale Climate Connections by Lexi Smith

Cost-benefit analysis (CBA) may sound like the realm of wonky bureaucrats tinkering on the edges of major policy initiatives. But CBA can have enormous consequences, especially in the context of climate change. When calculating climate harms, seemingly small assumptions made by economists can make or break a policy intervention.

Consider how we make decisions about future payoffs: Would you rather have a thousand dollars today or in a year? A rational actor’s decision would be to receive the money now because investing it will yield more money in a year’s time. This notion that the same amount of money is worth more now than in the future is applied in CBA as a “discount rate.” A discount rate is essentially an assumption about future returns to capital. When applied over long timescales in analyzing climate policy, discount rates value future generations at pennies on the dollar.

The federal government suggests using seven and three percent discount rates. With a discount rate of 7%, $5 trillion of damages from climate change in 2100 would be valued at about $24 billion in 2021. A 3% discount rate would yield $484 billion in 2021.  A seemingly small assumption yields wildly different results for how much we should spend to prevent harm to future generations. Furthermore, these rates rest on the assumption that the economy will continue to grow and create stable returns to capital over time. But as climate change worsens, the global economy may stagnate and destabilize, meaning growth assumptions baked into discount rates are no longer accurate. An assumption of economic growth is used to justify further emissions that may themselves destabilize growth.

To offer another example, say that an economist posits that damages from climate change will be linear and extrapolates those damages based on scientists’ predictions of harm for 1 to 3 degrees Celsius of warming. But at higher temperatures, runaway feedback loops could mean that the harms of climate change are far more serious than a linear model would predict. A cost-benefit analysis might find that a solar panel installation in your neighborhood won’t be justified after using its prediction of linear harm. But a more accurate model that accounts for the possibility of catastrophic harm could find that the solar panels are a sound investment.



2021 SkS Weekly Climate Change & Global Warming News Roundup #43

Posted on 24 October 2021 by BaerbelW

Listing of articles linked to on the Skeptical Science Facebook Page during the past week: Sun, October 17, 2021 through Sat, October 23, 2021

The following articles sparked above average interest during the week: Forget your carbon footprint. Let's talk about your climate shadow, People Who Jump to Conclusions Show Other Kinds of Thinking Errors, September 2021: Earth’s 5th-warmest September on record, Could search engines be fostering some Dunning-Kruger?, How extreme weather and the pandemic have exposed fatal flaws in science communication, The scientific consensus on climate change gets even stronger, and THE TRUTH WILL SET YOU FREE.

Articles Linked to on Facebook



Skeptical Science New Research for Week #42, 2021

Posted on 22 October 2021 by doug_bostrom

105 articles by 463 contributing authors

Physical science of climate change, effects

A simple model of blocking action over a hemisphere
Kurgansky Theoretical and Applied Climatology

Mechanisms of European Summer Drying under Climate Change
Tuel & Eltahir Alizadeh Journal of Climate
Open Access 10.1175/jcli-d-20-0968.1

Observations of climate change, effects

Hotter and drier climate made the Mediterranean Europe and Northern Africa region a shrubbier landscape
Fang et al. Oecologia
Open Access 10.1007/s00442-021-05041-3

Urbanization Exacerbated Rainfall over European Suburbs under a Warming Climate
Yang et al. Geophysical Research Letters

Decadal changes of the Intraseasonal Oscillation during 1979?2016
Nan et al. Advances in Climate Change Research
Open Access 10.1016/j.accre.2021.10.001

Urbanization-induced changes in extreme climate indices in Thailand during 1970–2019
Pimonsree et al. Atmospheric Research
Open Access 10.1016/j.atmosres.2021.105882

(provisional link) Historical Changes in the Davis Strait Baffin Bay Surface Winds and Waves, 1979–2016

(provisional link) Extreme Rainfall Events in the Northeastern United States Become More Frequent with Rising Temperatures, but Their Intensity Distribution Remains Stable



The scientific consensus on climate change gets even stronger

Posted on 21 October 2021 by John Cook

Over time, the scientific consensus on climate change has steadily strengthened as the empirical evidence has piled up.

We see this in the statements of the Intergovernmental Panel on Climate Change. In 1995, it suggested there was a discernible human influence on global climate – at the time it was a bold statement, and forever changed the life of lead author Ben Santer.

From that point, the language steadily strengthened from most of the warming being “very likely” due to human CO? emissions in 2007, to “extremely likely” in 2013.

Earlier this year, the latest IPCC report issued its most definitive statement, concluding that “[i]t is unequivocal that human influence has warmed the atmosphere, ocean and land”.

‘Cranky Uncle‘ cartoon depicting a timeline and a man progressively changing his mind about climate change



Kids’ quality of life will depend on today’s climate choices

Posted on 20 October 2021 by dana1981

This is a re-post from Yale Climate Connections

It’s the moral quandary of human-caused climate change: People least responsible for the problem will bear the brunt of its harmful consequences. As a substantial body of scientific research has established, this reality is true of developing countries. They generally are located in already-hot regions near the equator and lack needed financial resources to adapt to the changing climate.

As a new study in the journal Science illustrates, this conundrum applies also to younger generations being born into a carbon-intensive society and a world undergoing rapid climate change. Children born today will experience far more extreme weather impacts over their lifetimes than their grandparents, particularly those children born in vulnerable developing countries.

This issue of intergenerational climate impacts is also a critical consideration for economics and policy in the present day. Decisions about whether governments should invest money in climate solutions today, or save those funds to accrue interest in the future, are based on subjective choices and values. Would societies prefer that future generations inherit less economic debt but an increasingly destabilized climate with worse extreme weather impacts? The new Science study provides important context with which to weigh those choices.

Severe changes in extreme heat waves

More frequent and intense heat waves are the most direct consequence of global warming. Burning fossil fuels releases carbon that combines with oxygen in the air to form the greenhouse gas carbon dioxide, which traps more heat and thus raises Earth’s temperatures.

The latest report from the Intergovernmental Panel on Climate Change indicates that what was a 1-in-50-year extreme heat event in the late-1800s now happens five times more often – once per decade. As temperatures approach the Paris Climate Agreement target of 1.5 to 2 degrees Celsius (2.7 to 3.6 degrees Fahrenheit) above pre-industrial levels, that frequency will again double: The same extreme heat wave will occur once every five years.

The new Science study arrives at the same general conclusion but frames these impacts in a novel way, in terms of how frequently a cohort generation will experience the same level of extreme weather during their lifetimes. For example, what was a once-in-a-lifetime heat wave for a person born in the 1800s (a level of extreme heat happening just once in a century) will occur four times in the life of an individual born in 1960 (once per 20 years). A child born in 2020 will experience that same extreme heat wave 20 times (if the Paris targets are met) to 40 times (if governments merely follow through with current climate policies, resulting in 3°C or 5.4°F global warming) in his or her lifetime (once every two to four years), depending on the ambition and success of climate policy solutions.

The authors note that policy choices and future warming pathways will not significantly alter extreme heat exposure frequency for people born before 1980; those changes are already baked in. But today’s climate policy decisions could dramatically alter the world 0f the youngest (and yet-to-be-born) generations.



Ben Santer on ‘separating’ and his ‘small part’ in understanding of climate science

Posted on 19 October 2021 by Guest Author

This is a re-post from Yale Climate Connections

Separating is hard. I’ve spent most of my scientific career trying to separate observed climate records into human-caused signals and the background noise of natural variability. It’s been challenging and fascinating work. Challenging because so many different human and natural factors affect Earth’s climate. Each factor varies in space and time. We’ll never have perfect understanding of these variations.

It’s been fascinating work because science is ultimately about learning. Since the late 1970s, scientists have learned to recognize the characteristic fingerprints of human and natural influences on climate. Through this work, we know that humans are active agents of change in the climate system – not innocent bystanders. By burning fossil fuels, we’ve warmed our planet. That warming signal is now pervasive and irrefutable.

It’s been a rare privilege to have witnessed this evolution in scientific understanding and to have played a small part in it. 

Separating is also hard in real life. It’s tough to deal with the abrupt ending of a relationship, a marriage, or a friendship. It’s challenging to cope with the ending of long-term employment. There are many aspects of disentangling: financial; emotional; loss of identity, of meaning, of a shared vision of the future, of a daily routine. How will the separation affect those around you? What does it mean not only for you, but for family, friends, and colleagues?

The path from ‘heroic figure’ to ‘villain’ to … ‘Keep building’

I retired from Lawrence Livermore National Laboratory (LLNL) on October 1, 2021. I was at LLNL for nearly 30 years. Almost all my work was funded by the U.S. Department of Energy (DOE).

One part of my job at LLNL was to evaluate computer models of the climate system – to compare models and real-world climate data in a variety of different ways. To see how well climate models captured climate reality. Another part of my job was to fingerprint the climate system. I used pattern-based “fingerprint” methods developed by Professor Klaus Hasselmann to separate climate signals from intrinsic climate noise.

Let’s talk briefly about this separation problem. Climate change is both internally generated and externally forced. The internally generated part arises from a veritable “zoo” of intrinsic modes of natural variability. Some of these zoo inhabitants are well-known outside of scientific circles, such as El Niños and La Niñas. Other zoo denizens – like the Madden-Julian Oscillation – are less familiar to the public. Together, these internal oscillations generate climate variability on a wide range of different space and timescales. This is the background noise against which a human-caused global warming signal must be identified. 

External influences on climate are fundamentally different beasts. They involve changes in factors external to the physical climate system, such as human-caused increases in atmospheric greenhouse gas levels or purely natural fluctuations in the Sun’s energy output. Each external influence causes a unique pattern of climate change – a fingerprint. The uniqueness can show up in geographical patterns of climate change, or in patterns that are slices through the vertical extent of the atmosphere or oceans



Geert Jan van Oldenborgh, 1961–2021

Posted on 18 October 2021 by

This is a re-post from World Weather Attribution

With deepest sadness we must share with you the news that Geert Jan van Oldenborgh, dear friend, amazing scientist, co-founder and co-leader of World Weather Attribution, husband and father, and a wonderful human, passed away on 12 October 2021.

Geert Jan trained as a physicist and started working on climate in 1996, when he joined KNMI as a postdoc. In the 2000s, he created the “Climate Explorer”, a platform to analyse climate data. He did so single-handedly and with little funding; it remains one of the most useful tools for accessing and analysing climate data available to the world. His desire to share everything he made, and for science, data and tools to be open, advanced climate science and meant that results were more easily accessible for the general public.

Geert Jan realised we needed to answer not just the simple questions, or those with the most immediate scientific rewards, but the ones that mattered. He was deeply motivated to make his science valuable to society and especially to the most vulnerable, as reflected in some of the earliest analyses of changing extremes in Africa and his pioneering work on rapid attribution of extreme events

As the joint founder and leader of WWA, Geert Jan was central to its work to investigate and explain how climate change is influencing weather today. His work received growing scientific, political and social attention: this year alone he was recognised with a royal honour in the Netherlands, the European Meteorological Society’s Technology Achievement Award and Time Magazine’s listing of the world’s most influential people. Attribution science was identified as one of the “breakthrough technologies” of 2020 by the MIT Technology Review, and was one of the major advances reported in the IPCC’s Sixth Assessment Report.

Beyond his scientific achievements, Geert Jan was a passionate, generous and inspirational colleague, friend and role model to his collaborators at WWA and to many others. His honesty, kindness and morality shone through his life and work, leaving fellow scientists, students and friends mourning his loss but grateful for having known and worked with him. His legacy will be immense.

Reflections from some of us, Geert Jan’s WWA colleagues:

“He was one of the really great ones, but he didn’t have a big ego, he never quite believed just how good he was. He was not recognised enough. Geert Jan taught me so much, but the most important thing was to have fun in your work. And he was so much fun to work with.”



2021 SkS Weekly Climate Change & Global Warming News Roundup #42

Posted on 17 October 2021 by BaerbelW

Listing of articles linked to on the Skeptical Science Facebook Page during the past week: Sun, October 10, 2021 through Sat, October 16, 2021

The following articles sparked above average interest during the week: ‘This is a story that needs to be told’: BBC film tackles Climategate scandal, Why trust science?, Overconfident Idiots: Why Incompetence Breeds Certainty, Ben Santer on ‘separating’ and his ‘small part’ in understanding of climate science, Make electric vehicles lighter to maximize climate and safety benefits, and Trust in meteorology has saved lives. The same is possible for climate science.

Articles Linked to on Facebook



Faster transitions to clean energy are also cheaper

Posted on 15 October 2021 by dana1981

This is a re-post from the Citizens' Climate Lobby blog

Several clean energy technologies like solar panels have become consistently cheaper year after year as the industries have benefited from learning, experience and economies of scale. Falling solar costs are described by “Swanson’s Law,” much like Moore’s Law described the rapid and consistent progress in the semiconductor industry. Solar photovoltaic cells in 2019 cost about 85% less per watt than they had in 2010, for example. This raises the question: should we expect the cost of renewable energy technologies to stop falling and plateau?

That’s an assumption that many influential energy-economy modelers have made in the past, but they’ve been wrong every single time. For example, their analyses forecast on average that between 2010 and 2020 solar panel costs would fall by 2.6% annually. In reality, solar costs fell more than five times faster than that, at 15% per year.

According to a new working paper from the Institute for New Economic Thinking at Oxford, energy-economy modelers should update their assumptions to anticipate that the costs of key clean technologies will keep falling as their industries continue to benefit from deployment experience and Swanson’s Law. As the authors noted, the assumptions and forecasts from these models have important real-world impacts on energy decisions, economics, and climate change:

“Failing to appreciate cost improvement trajectories of renewables relative to fossil fuels not only leads to under-investment in critical emission reduction technologies, it also locks in higher-cost energy infrastructure for decades to come.”

More realistic assumptions

Many experts have called for energy economics modelers to find better approaches that will more accurately predict the future evolution of clean energy technologies. By assuming that clean energy costs will keep falling as the industries continue to benefit from learning and experience curves as the technologies are deployed, the Oxford study forecast that in 2050:

  • Energy from solar panels will be about 66% to 86% cheaper than today, most likely 80% cheaper.
  • Energy from wind turbines will be about 5% to 50% cheaper than today, most likely 30% cheaper.
  • Lithium-ion batteries will be about 80% to 94% cheaper than today, most likely 90% cheaper.
  • Producing “green hydrogen” by electrolyzing water (splitting water molecules into hydrogen and oxygen atoms, which can be done using renewable energy), will be about 60% to 97% cheaper than today, most likely 90% cheaper.

Faster transitions to clean energy are also cheaper

Levelized cost of energy (LCOE) for solar cells from 1980 to 2020 (black dots), as previously inaccurately forecast by influential energy-economy models (red lines), and as forecast in the Oxford working paper (blue dashed line and shaded regions), with the historical and forecast experience curve similarly shown in the bottom left corner. Source: Oxford working paper.

Unlike renewable energy, the costs of fossil fuels and the electricity they generate have remained essentially flat over the past many decades and are forecast to remain steady in the future as well. This is why a price on carbon is one of the most influential climate solutions — it would increase the price of fossil fuels and drive our economy toward these affordable, renewable options even faster than predicted.



Skeptical Science New Research for Week #41, 2021

Posted on 14 October 2021 by doug_bostrom

How to fill a glass and thereby drink— from a fire hose

So far this year, New Research has published listings for 3,291 papers concerning climate change from one aspect or another. Each edition includes two dozen or so articles describing freshly and directly observed effects of global waming. These papers as a sampling should fully convey the profound nature of changes we're experiencing even now, but the sad truth is that we're only skimming the surface.  Compilation time is limited, and probably reader attention as well. Meanwhile, on a planet of 7+ billion persons even a tiny fraction motivated to research matters related to climate change translates into a sizable army of investigators and a torrent of publications. What we list is a drop in the bucket.

Fortunately, if we're looking for certain kinds of information it turns out there's silicon and software to to help. Employing the natural language representation model BERT, a lot of mental sweat equity and doubtless a few kilowatt hours Max Callaghan and coauthors evaluated over half a million research publications to wring out some specific information: how many people inhabit regions directly affecte by anthropogenic climate change, today?  Given the essentially seamless nature of Earth systems and the continuum from one geophysical domain to another, we'd expect a lot. As it turns out and as best the authors are able to deduce via machine-aided analysis of over 600,000 research papers, about 85% of us may already be living in a climate altered by our own species. 

It's not idle curiosity in play here. Keen not to waste prior effort, the authors have effectively created something that might be termed a literature review— but on a scale never seen before. Still, we see the familiar intention of deriving practical value and guidance from a diversity of source material. In the authors' words:

In the climate science community, evidence-based assessments of observed climate change impacts are performed by the Intergovernmental Panel on Climate Change (IPCC) . Since the first Assessment Report (AR) of the IPCC in 1990, we estimate that the number of studies relevant to observed climate impacts published per year has increased by more than two orders of magnitude (Fig. 1a). Since the third AR, published in 2001, the number has increased ten-fold. This exponential growth in peer-reviewed scientific publications on climate change 5,6 is already pushing manual expert assessments to their limits. To address this issue, recent work has investigated ways to handle big literature in sustainability science by scaling systematic review and map methods to large bodies of published research using technological innovations and machine learning methods.

Machine-learning-based evidence and attribution mapping of 100,000 climate impact studies  is open access, free  to read, and with a trove of interesting citations to follow. 



Overconfident Idiots: Why Incompetence Breeds Certainty

Posted on 13 October 2021 by Guest Author

TiP-LogoThis is a re-post from the Thinking is Power website maintained by Melanie Trecek-King where she regularly writes about many aspects of critical thinking in an effort to provide accessible and engaging critical thinking information to the general public. Please see this overview to find links to other reposts from Thinking is Power.


The Dunning-Kruger effect explains why stupid people think they’re amazing.

On a sunny day in 1995, a man walked into a Pittsburgh bank. He smiled at the security cameras, pointed a gun at the cashiers, and demanded they give him money. 

A few hours later, he robbed a second bank. 

At 5 feet 6 inches tall and 270 pounds, the man wasn’t hard to miss. Especially since he wasn’t wearing a mask. 

The evening news aired images of the man’s face to help the police identify the robber. They had his name within an hour, and immediately went to 45 year-old McArthur Wheeler’s home to arrest him.

Wheeler was dumbfounded. He couldn’t believe he had been caught. He didn’t even try to proclaim his innocence. Instead, he kept repeating, “But I wore the juice.”

During interrogation, Wheeler told the police he couldn’t understand how the security cameras had captured his image, because he had smeared lemon juice on his face to make himself invisible. The police assumed he was on drugs or alcohol. But nope. He was sober.

Just really, really wrong.

Apparently, Wheeler had learned that lemon juice could be used as an invisible ink, and concluded he could make himself invisible by rubbing it on his face. Of course, he wasn’t stupid, so he made sure to test his hypothesis. He put lemon juice on his face and took a selfie with a Polaroid camera. The blank photo proved his idea worked. Bam. He had discovered a fool-proof way to commit crimes and not be caught.

The day of the robbery, he put so much lemon juice on his face that it stung his eyes, making it hard for him to see. He marched into the bank, bare faced and smiling, confident that no one could see him.



Young adults worldwide have blunt message for governments: ‘We don’t trust you.’

Posted on 12 October 2021 by Guest Author

This is a re-post from Yale Climate Connections by Karin Kirk

Elizabeth Marks describes herself as “a psychologist who works on difficult problems.” Her past research aimed at helping people cope with challenging health conditions, apt training, it appears, for taking on climate change issues.

A few years ago, she altered the course of her research. “I really needed to do something in my working life that aligned with my values,” she said, describing her recent efforts to study people’s emotions around climate change. She has a reassuring tone and she’s a terrific listener – attributes one would hope to find in a psychologist.

Climate anxiety has become a sadly familiar topic, and as with many aspects of climate change, the problem has shifted from an abstract notion to a symptom many are now experiencing personally. Wildfire smoke chokes the sky, even at great distance from the fires themselves. Streets and subways fill with floodwaters, and the power grid falters under pressure wrought by extreme weather.

As the reality of climate change becomes increasingly evident, Marks says, “a lot of people will feel some level of distress.”

Marks is a lead author on a recent study, “Young People’s Voices on Climate Anxiety, Government Betrayal and Moral Injury: A Global Phenomenon,” in pre-print in The Lancet. The paper sheds new light on climate anxiety, measuring  how  teens and young adults feel about governmental responses to climate change. Young people across the globe expressed an unequivocal admonishment of governments’ tepid actions thus far to address climate change.

The pre-print phase means the paper still is undergoing the peer review process. Results from this work are consistent with public opinion research recently published by the Pew Research Center, showing young people are more concerned about climate change and are more motivated to take action on climate than older adults.

Among those surveyed by Marks and her coauthors, young people in the U.S. expressed the lowest levels of trust in government, and American young adults overwhelmingly said that their climate concerns are not being taken seriously enough.

“Young people in this study are really, clearly telling us how they feel,” says Marks. “I think the most important influence they can have is for us to listen to them.”



My Climate Science PhD (at @University of Oxford )

Posted on 11 October 2021 by Guest Author

I began working on climate change through my doctorate in atmospheric physics at the University of Oxford. But ten years on, it's time I actually explained what my research is about... and why I'm not researching any more!

Support ClimateAdam on patreon:



2021 SkS Weekly Climate Change & Global Warming News Roundup #41

Posted on 10 October 2021 by BaerbelW

Listing of articles linked to on the Skeptical Science Facebook Page during the past week: Sun, October 3, 2021 through Sat, October 9, 2021

The following articles sparked above average interest during the week: VFX Artist Reveals how Many Solar Panels are Needed to Power the ENTIRE World, Will you fall into the conspiracy theory rabbit hole? Take our quiz and find out., Nobel Prize in Physics won by 3 scientists for discoveries in climate and complex physical systems, Deniers Blame Alarmists for Journal Retraction of "Deeply Flawed" Pal-Reviewed Paper and Revealed: Two Thirds of Online Posts from Six Major European Fossil Fuel Companies ‘Greenwashing’.

Articles Linked to on Facebook



Skeptical Science New Research for Week #40, 2021

Posted on 7 October 2021 by doug_bostrom

"Old" research

There's little point in trying to best this excellent article describing the 2021 Nobel Prize in Physics by Ars Technica authors Jennifer Ouelette and John Timmer, each having a gift for concisely on-target, accessible science journalism. Here at New Research we'll punt and quote the The Royal Swedish Academy of Sciences press release, then follow up with a sampling of open-access papers authored by the prize recipients. Ouellette and Timmer's article supplies a lot of missing context and is well worth a visit.

The 2021 Nobel Prize in Physics is awarded to Syukuro Manabe, Klaus Hasselmann & Giorgio Parisi. Here's why, according to the Nobel Committee for Physics:

Complex systems are characterised by randomness and disorder and are difficult to understand. This year’s Prize recognises new methods for describing them and predicting their long-term behaviour.

One complex system of vital importance to humankind is Earth’s climate. Syukuro Manabe demonstrated how increased levels of carbon dioxide in the atmosphere lead to increased temperatures at the surface of the Earth. In the 1960s, he led the development of physical models of the Earth’s climate and was the first person to explore the interaction between radiation balance and the vertical transport of air masses. His work laid the foundation for the development of current climate models.

About ten years later, Klaus Hasselmann created a model that links together weather and climate, thus answering the question of why climate models can be reliable despite weather being changeable and chaotic. He also developed methods for identifying specific signals, fingerprints, that both natural phenomena and human activities imprint in the climate. His methods have been used to prove that the increased temperature in the atmosphere is due to human emissions of carbon dioxide.

Around 1980, Giorgio Parisi discovered hidden patterns in disordered complex materials. His discoveries are among the most important contributions to the theory of complex systems. They make it possible to understand and describe many different and apparently entirely random materials and phenomena, not only in physics but also in other, very different areas, such as mathematics, biology, neuroscience and machine learning.

“The discoveries being recognised this year demonstrate that our knowledge about the climate rests on a solid scientific foundation, based on a rigorous analysis of observations. This year’s Laureates have all contributed to us gaining deeper insight into the properties and evolution of complex physical systems,” says Thors Hans Hansson, chair of the Nobel Committee for Physics.

Some papers by the recipients, from the critical periods mentioned by the committee (open access):


Simulated climatology of a general circulation model with a hydrologic cycle 

Thermal equilibrium of the atmosphere with a convective adjustment 

The Effects of Doubling the CO2 Concentration on the climate of a General Circulation Model 


Stochastic climate models part I. Theory 

Stochastic climate models, Part II Application to sea-surface temperature anomalies and thermocline variability 

Multi-pattern fingerprint method for detection and attribution of climate change 


Infinite Number of Order Parameters for Spin-Glasses 

Order Parameter for Spin-Glasses 

The order parameter for spin glasses: a function on the interval 0-1


117 articles by 633 contributing authors

Observations of climate change, effects

Warming Climate Shortens Ice Durations and Alters Freeze and Breakup Patterns in Swedish Water Bodies
Hallerbäck et al.
Open Access pdf 10.5194/tc-2021-304

Variations in Summer Marine Heatwaves in the South China Sea
Yao & Wang Journal of Geophysical Research: Oceans

Phenological trends in the pre- and post-breeding migration of long-distance migratory birds
Lawrence et al. Global Change Biology

Trends of freezing period and its main cause on the Qinghai-Tibetan Plateau from 1961 to 2018
Zhao et al. Theoretical and Applied Climatology
Open Access 10.1007/s00704-021-03798-4

A Secular Shift of the Madden-Julian Oscillation and Its Relation to Western Pacific Ocean Warming
Huang et al. Geophysical Research Letters

Climate signatures on lake and wetland size distributions in arctic deltas
Vulis et al. Geophysical Research Letters
Open Access 10.1002/essoar.10507143.1

Distinct tropospheric and stratospheric mechanisms linking historical Barents-Kara sea-ice loss and late winter Eurasian temperature variability
Xu et al. Geophysical Research Letters

Climate driven trends in London's urban heat island intensity reconstructed over 70 years using a generalized additive model
Bassett et al. Urban Climate

Natural and Anthropogenic Forcing of Multi-decadal to Centennial Scale Variability of Sea Surface Temperature in the South China Sea
Goodkin et al. Paleoceanography and Paleoclimatology

Winter daytime warming and shift in summer monsoon increase plant cover and net CO2 uptake in a central Tibetan alpine steppe ecosystem
Nieberding et al. Journal of Geophysical Research: Biogeosciences
Open Access 10.1002/essoar.10507017.1

Decreasing subseasonal temperature variability in the northern extratropics attributed to human influence
Blackport et al. Nature Geoscience



Fighting back against climate misinformation and the damage being done

Posted on 6 October 2021 by John Cook

Misinformation about climate change has polluted our information landscape for three decades, poisoning public discourse and clouding minds. We tend to think that the main danger of misinformation is causing people to believe wrong things. But there are a multitude of ways that it does damage.

Misinformation builds distrust of scientists and scientific institutions—a dangerous trend during a pandemic when public health depends on people following the advice of scientific experts.

An insidious element of misinformation is it can cancel out accurate information. When people are confronted with conflicting information (e.g., fact and myth) and no way to resolve the conflict, the danger is they disengage and believe neither. This means that if we ignore the threat of misinformation, we leave the public (and our efforts to communicate accurate information) vulnerable to misinformation.

Read more Is it time to rethink our language on climate change?

Climate misinformation has a polarising effect, having a greater influence on political conservatives. This means that as misinformation washes over society, people move further away from each in their views about climate change. Consequently, we’ve seen the issue become more and more polarised over the years, making progress on climate action more difficult.

Climate change misinformation graphic.

Nowadays, the misinformation problem is a perfect storm of overlapping factors. Social media platforms act like 24/7 superspreader events, efficiently distributing misleading and inflammatory content to an eager but “unvaccinated” population.

The degree of polarisation has intensified to the point that the biggest factor determining people’s views on climate change is not education level but which political party they vote for. And politicians exploit public polarisation by peddling more misinformation that inflames their base, further exacerbating the problem.



Estimates of the economic damages from climate change

Posted on 5 October 2021 by ATTP

This is a re-post from ATTP's blog

Since I’ve discussed climate economics before, I thought I would briefly highlight a recent seminar involving, amongst others, Steve Keen and Tim Lenton. The topic was are the estimates of economic damages from climate change erroneous? The basic answer to this questions is yes.

The presenters make a number of good points. Steve Keen highlights how there is little empirical support for the damage functions. There are attempts to estimate how economic activity depends on climate, but there is a huge difference how it might vary in different regions of the planet today, and how it might be impacted by global warming of a similar magnitude.

Tim Lenton highlighted how we may already be close to triggering certain tipping elements and how these economic analyses tend to ignore such outcomes, or may even not be able to properly consider them. In one economic analysis, it was suggested that the collapse of the Atlantic Meridional Overturning Circulation (AMOC) may have a positive economic impact because it might slightly dampen global warming. As Tim Lenton pointed out, this was an “insane” result given that such a collapse would result a major reorganisation of the entire climate system.

Matheus Grasselli, another of the speakers, presented quite a detailed analysis of William Nordhaus’s DICE model. He highlighted how it essentially assumes that the system is always in equilibrium, even if there has been some major shock. He also showed how the results depended strongly on assumptions about damages. What I thought was particularly interesting is that in the DICE model, everything seems to recover even in extreme scenarios.



Hot, dry, and smoky: Iconic Yellowstone has much to lose with climate change

Posted on 4 October 2021 by Guest Author

This is a re-post from Yale Climate Connections by Kristen Pope

Home to the world’s first national park, the Greater Yellowstone Area (GYA) is a vast ecological powerhouse that comprises 22 million acres in three states – Wyoming, Montana, and Idaho. Wildlife like grizzly and black bears, wolves, elk, moose, bison, bald eagles, and even wolverines, make the area their home – as do humans.

Residents and visitors alike savor the region’s outdoor recreation opportunities, from hiking, camping, fishing, boating, sightseeing, and wildlife watching to winter sports like skiing and snowmobiling. This summer, researchers published the Greater Yellowstone Climate Assessment, analyzing impacts of climate change on the entire ecosystem, including portions of six watersheds.

“Right now we have national assessments and some state assessments, like the Montana Climate Assessment, but we don’t really have climate assessments that focus on ecosystems,” says Cathy Whitlock, co-lead author of the Greater Yellowstone Climate Assessment. “And, of course, Greater Yellowstone is the grand ecosystem in the country,”  

Whitlock, regents professor emerita of earth sciences at Montana State University, was the first author on the 2017 Montana Climate Assessment. She explains, “I wanted to work on an effort that would look at an ecosystem that crosses state boundaries and different jurisdictions, from federal land to private land, so that we could look at that as a coherent entity.”

University of Montana Regents Professor Emeritus Steven Running says the ecosystem-level nature of the report makes it easier for people to relate to the findings, rather than trying to understand global temperature and rainfall averages in wider reports. “I think as you get down to the region, in effect the people’s backyard, then it allows them to absorb the information better because it’s familiar to what they live in every day,” Running says.

Whitlock and co-lead author Steve Hostetler, a U.S. Geological Survey climate researcher, collaborated with a team including experts from the U.S. Geological Survey, Montana State University, University of Wyoming, Greater Yellowstone Coalition, Midpeninsula Regional Open Space District, and Mountain Works, Inc.

The scientists analyzed Greater Yellowstone Area weather station data going back to 1950 and streamflow records from as long ago as 1925. Their report focuses on how climate change is already impacting the region and what the future could hold by 2100. Projections focus on two potential greenhouse gas emissions scenarios. RCP4.5 (RCP stands for Representative Concentration Pathways) is a moderate scenario “assuming significant mitigation of emissions beginning in the next few years.” RCP8.5 demonstrates a potential future with no greenhouse gas emissions mitigation, what some call a “business as usual” approach.



2021 SkS Weekly Climate Change & Global Warming News Roundup #40

Posted on 3 October 2021 by BaerbelW

Listing of articles linked to on the Skeptical Science Facebook Page during the past week: Sun, September 26, 2021 through Sat, October 2, 2021

The following articles sparked above average interest during the week: Ex-Fox host claims Facebook defamed him by fact-checking climate change videos (by a wide margin!), How Skepticism Can Protect You From Being FooledFighting back against climate misinformation and the damage being done, Climate change risk assessment 2021, and Ocean Conveyor Systems.

Articles Linked to on Facebook



What role for small modular nuclear reactors in combating climate change?

Posted on 1 October 2021 by greenman3610

This is a re-post from Yale Climate Connections

Does the potential of small modular nuclear reactor technology make it a viable approach to helping solve climate change challenges not fully met by renewable energy sources such as wind and solar?

Experts interviewed in this Yale Climate Connections “This is Not Cool” original video in some cases hold out hope. But they also confront timing, economic, and communications obstacles that could be prohibitive.

Other Lab Chief Executive Officer Saul Griffith voices what he characterizes as “an extraordinary position … but hopefully not too extraordinary a postilion.” Nuclear energy, Griffith says, “has been pretty reliable and very safe and compared to other energy sources, all told, reasonably priced …. and good.” But he backtracks some: He readily acknowledges “huge political headwinds” and concerns about availability of adequate cooling water supplies, a view expressed also by water resources expert Peter Gleick. Griffith points to what many – among them proponents of nuclear energy – fear may be an Achilles heel: “It’s unclear if safe and reliable nuclear energy can compete with just where solar and wind are going …. That’s the reality.”

University of California Berkeley nuclear engineering professor Daniel Kammen says he’s hoping nuclear energy can fill some needs that renewables may not resolve. But he points to a stiff “learning curve.” In addition, Kammen says “There’s more work to be done on nuclear than on any other area for it to be a competitor.”



The Consensus Project Website


(free to republish)

© Copyright 2021 John Cook
Home | Links | Translations | About Us | Privacy | Contact Us