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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.


Skeptical Science New Research for Week #46, 2021

Posted on 25 November 2021 by Doug Bostrom, Marc Kodack

104 articles by 574 contributing authors

Physical science of climate change, effects

Delayed impacts of Arctic sea-ice loss on Eurasian severe cold winters
Jang et al. Journal of Geophysical Research: Atmospheres

Observations of climate change, effects

Divergent responses of terrestrial carbon use efficiency to climate variation from 2000 to 2018
Gang et al. Global and Planetary Change

(provisional link) Isotopic evidence of increasing water abundance and lake hydrological change in Old Crow Flats, Yukon, Canada

Global increase in wildfire risk due to climate driven declines in fuel moisture
Ellis et al. Global Change Biology

Weather Whiplash: Trends in rapid temperature changes in a warming climate
Lee International Journal of Climatology

The Role of Intensifying Precipitation on Coastal River Flooding and Compound River-Storm Surge Events, Northeast Gulf of Mexico
Dykstra & Dzwonkowski Water Resources Research

Wildfire response to changing daily temperature extremes in California’s Sierra Nevada
Gutierrez et al. Science Advances
Open Access pdf 10.1126/sciadv.abe6417

Changes in snow cover occurrence and the atmospheric circulation impact in Pozna? (Poland)
Szyga-Pluta Theoretical and Applied Climatology
Open Access pdf 10.1007/s00704-021-03875-8



Thanksgiving advice, 2021: How to deal with climate change-denying Uncle Pete

Posted on 24 November 2021 by Guest Author

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

“Birds of a feather flock together,” so I am sure that nearly all of those reading this article accept the main findings of climate science. Yet many people don’t. Instead, they believe a variety of climate myths.

These include claims that the world isn’t warming; or if warming is occurring, it is natural and not human-caused; or that volcanoes produce more carbon dioxide than we humans do. I know none of you believes these myths, but it seems that almost everybody has an unpleasant relative—call him Uncle Pete—who does, and who comes to dinner. Pete spoils the family mood by making these false claims, which he found on talk radio or the Internet.

I don't believe in global warming Graffiti in London, possibly the work of noted street artist Banksy. Image courtesy of Matt Brown/Pixabay

I’ll tell you in a moment why some of the most frequently repeated claims are just plain wrong. I won’t have time to cover all of them, and I recommend the website for the whole story. It’s a collection of the most commonly heard climate myths, and why they are all dead wrong. is your key to refuting your own Uncle Pete.

Start with the myth that the warming we have observed in recent decades is natural and not human-caused. First off, let’s be clear: The climate has indeed changed naturally in the past, with ice ages being an obvious example. But natural causes simply cannot explain the recent warming. How do we know that? It’s very like the story of wildfires, which can be caused naturally, by lightning. But they can also be caused by people, either by carelessness or by arson. And wildfire experts can investigate after a wildfire and determine what caused it. They know how to do the detective work.



Global CO2 emissions have been flat for a decade, new data reveals

Posted on 23 November 2021 by Zeke Hausfather

This is a re-post from Carbon Brief

Global carbon dioxide (CO2) emissions from fossil fuels and cement have rebounded by 4.9% this year, new estimates suggest, following a Covid-related dip of 5.4% in 2020.

The Global Carbon Project (GCP) projects that fossil emissions in 2021 will reach 36.4bn tonnes of CO2 (GtCO2), only 0.8% below their pre-pandemic high of 36.7GtCO2 in 2019.

The researchers say they “were expecting some sort of rebound in 2021” as the global economy bounced back from Covid-19, but that it was “bigger than expected”.

While fossil emissions are expected to return to near-record levels, the study also reassesses historical emissions from land-use change, revealing that global CO2 output overall may have been effectively flat over the past decade.

The 2021 GCP almost halves the estimate of net emissions from land-use change over the past two years – and by an average of 25% over the past decade.

These changes come from an update to underlying land-use datasets that lower estimates of cropland expansion, particularly in tropical regions. Emissions from land-use change in the new GCP dataset have been decreasing by around 4% per year over the past decade, compared to an increase of 1.8% per year in the prior version. 

However, the GCP authors caution that uncertainties in land-use change emissions remain large and “this trend remains to be confirmed”.

The GCP study, which is not yet peer-reviewed, is the 16th annual “global carbon budget”. The budget also reveals:

  • China and India both surpassed their 2019 emission peaks in 2021. Chinese emissions grew by 5.5% between 2019 and 2021, while Indian emissions grew by 4.4%. 
  • Chinese coal use was a particularly large driver of the global rebound in emissions, with the power and industry sectors in China the main contributors. 
  • Coal, oil and gas all fell during the pandemic, but both coal and gas emissions have already surpassed their pre-pandemic levels, with a 2% increase in gas emissions and a 1% increase in coal emissions between 2019 and 2021. 
  • Oil emissions remain around 6% below 2019 levels and this persistent reduction is one of the main reasons 2021 emissions did not set a new record.

The new updates to global CO2 emissions in the GCP substantially revise scientists’ understanding of global emissions trajectories over the past decade. The new data shows that global CO2 emissions have been flat – if not slightly declining – over the past 10 years. 

However, falling land-use emissions have counterbalanced rising fossil CO2 emissions, and there is no guarantee these trends will continue in the future.   



How will carbon pricing impact inflation?

Posted on 22 November 2021 by dana1981

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

Inflation — the decline of purchasing power as prices rise — is currently at its highest level in 30 years. This has led to concern among the public and policymakers about the rising costs of many important products like food, shelter, gasoline, electricity, and cars. Senator Joe Manchin has said he will not “support a package that risks hurting American families suffering from historic inflation.” As a result, CCL has received many inquiries from congressional offices, volunteers, and other stakeholders regarding the potential impact a carbon price would have on inflation.

The short answer is that well-designed carbon pricing legislation — like the Energy Innovation and Carbon Dividend Act (EICDA) and those currently under consideration by the Senate Finance Committee — includes a dividend returned to most or all American households precisely to address the resulting rise in energy costs. Inflation creates a problem when prices rise and household incomes don’t increase commensurately, but a dividend program can overcome that problem by sending carbon cashback to households.

Moreover, a recent review of carbon pricing systems in Canada and Europe found that contrary to economic modeling predictions that carbon fees will cause inflation, carbon fees have actually had the opposite effect in the real world.

What do economic models say about carbon pricing and inflation?

The answer to this question depends on the level of the carbon price and the rate at which it rises. According to modeling by the Columbia Center on Global Energy Policy (CGEP), the EICDA would add approximately 2.4 points to inflation over 10 years, or 0.24% per year. For comparison, the Federal Reserve aims for a 2% annual inflation rate. Moreover, the carbon pricing structures currently under consideration by the Senate Finance Committee will likely rise significantly more slowly than the EICDA, and thus have even less impact on inflation.

A carbon price included in the budget reconciliation process would also likely exempt retail gasoline (which would have a relatively small effect on the resulting carbon emissions cuts), and thus would not impact gasoline prices. According to modeling analyses by Resources for the Future and CGEP, a carbon price of $20 per ton would raise average U.S. electricity prices by about 0.5–1 cent per kilowatt-hour, and average household electricity bills by only about $4–8 per month. As the carbon price rises, so would average electricity bills, but the dividend would increase as well to offset those costs.



2021 SkS Weekly Climate Change & Global Warming News Roundup #47

Posted on 21 November 2021 by BaerbelW

Listing of articles linked to on the Skeptical Science Facebook Page during the past week: Sun, November 14, 2021 through Sat, November 20, 2021

The following articles sparked above average interest during the week: Do Androids Dream Of Electric Sheeple? A.I. Maps 20 Years of Climate Conspiracies, COP Negotiators Demand Nations do More to Curb Climate Change, but Required Emissions Cuts Remain Elusive, Five things you need to know about the Glasgow Climate Pact, COP26: The truth behind the new climate change denial, How Exxon duped "The Daily", and How to talk about climate change: Ask questions.

Articles Linked to on Facebook



Skeptical Science New Research for Week #46, 2021

Posted on 18 November 2021 by Doug Bostrom, Marc Kodack

Housekeeping: New content

New Research is primarily focused on reports published in "the academic literature." Thanks to a diversity of publishers, journals, editors, reviewers, researchers and institutional affiliations, such publications are statistically highly successful at approximating and reflecting our best dispassionate understanding of research topics. Any given personal agenda not primarily connected to expanding our horizon of understanding is more or less necessarily diluted in the baroque review/publication process.

While acknowledging the intentional effects of the academic publication system, it does not follow that what is printed elsewhere cannot also enhance our current understanding of climate change. Non-governmental organizations (NGOs) publish reports and reviews relevant to particular organizational missions and it's not axiomatic that these connections mean such material is so colored by their agenda and stated mission so as to be unworthy of our attention. Meanwhile, government agencies are frequently charged with producing assessment and analysis reports for lawmakers, other researchers and the general public, frequently compiled to a very high standard As with NGO work these publications often serve as highly valuable big picture snapshots, synthesizing a lot of sources into a coherent narrative and exposition. Meanwhile, some civilian and military agencies produce formal primary research essentially lacking only a DOI in distinction against academic publications. These alternate sources often benefit from reasonably rigorous peer-review processes that while not identical to those in the academic world do still serve to form a baseline of reliability.

So, we’re leaving a bit of dessert on the table by ignoring a lot of good work. Now that Marc Kodack has signed on to New Research we have some freeboard to deal with the problem.Marc is accustomed to swimming in the ocean of material we've been missing and— quite frankly— brings the time and energy needed to contemplate taking on more publications. Taking all of this into account New Research will feature a new topic section composed of climate-related publications from the NGO/government wellsprings.

As with other New Research sections, edition-to-edition our new feature will grow, shrink or even vanish as suitable material is or is not available. What appears in this new section will be publications of NGO/government provenance leaning hard in the direction of straight information, with minimal mission-specific coloration; we'll of course strive to identify reports with solid value. Links to these publications will be a bit different than for academic publications given that NGO/governmental publication are not part of the DOI system. As we become accustomed to this new input we may adjust our methods.

In order to clearly delineate between academic research and that with a more objective purpose in mind, listings of NGO/government reports appear in their own section, after our "traditional" fare. 

112 articles by 654 contributing authors

Physical science of climate change, effects

Drawdown of Atmospheric pCO2 via Variable Particle Flux Stoichiometry in the Ocean Twilight Zone
Tanioka et al. Geophysical Research Letters
Open Access 10.1002/essoar.10507405.2

(provisional link) On the Controlling Factors for Globally Extreme Humid Heat

A review of interactions between ocean heat transport and Arctic sea ice
Docquier & Königk Environmental Research Letters
Open Access 10.1088/1748-9326/ac30be



Climate challenges mount for California agriculture

Posted on 17 November 2021 by Guest Author

This is a re-post from Yale Climate Connections by Jan Ellen Spiegel

California agriculture has experienced just about every form of climate change-induced calamity: Heat, drought, fire, floods. None bodes well for the future of farming in this state that is the U.S. king of agriculture.

But there are a couple of less headline-worthy factors that may determine what crops will survive if climate change trends don’t at least slow down. One is the state’s winters – yes, winters – and the other is its management of groundwater.

Challenges ahead for sure. In the end, however, there for some is optimism that the California agriculture communities’ ability to continue adapting gives reasons for hope.

The importance of ‘chill hours’ for key crops

“Wintertime lows have gotten warmer,” says Dan Sumner, the Frank H. Buck, Jr. Distinguished Professor of Agricultural and Resource Economics at the University of California, Davis and a California farming region native. “We all talk about it in the middle of the summertime because it’s hot outside, but the real news is the wintertime lows.”

The reason? Perennial crops, comprising the bulk of California’s top farm commodities, need off-season dormancy to regenerate, so temperatures must remain below a certain threshold for at least a minimum amount of time. That concept is called “chill hours.” It’s crop-specific, and the fruits and nuts that are among the bedrocks of California agriculture are the ones most needing the right number of chill hours. Otherwise fewer buds, smaller fruits, lower yields.

According to the most recent census data from the U.S. Department of Agriculture, California still provides more agricultural product than any other state, accounting for 11% of the national total.  That output includes more than two-thirds of the nation’s fruits and nuts and more than one-third of the nation’s vegetables.

California’s top 10 agricultural commodities among its more than 400 in order are: dairy products, almonds, grapes, pistachios, cattle, lettuce, strawberries, tomatoes (largely for processing), floriculture, and walnuts.

Those are largely perennials needing their chill hours to make them as productive as they need to be, and therefore worth growing. Crops such as nut trees and grapes are large investments, so low yields may make them money losers.



Sea level rise: Uncertain Climate Future [with DrGilbz]

Posted on 16 November 2021 by Guest Author

What will the Sea Level Rise of tomorrow look like? The truth is there's still a big range of possibilities, and scientists are struggling to pin down the processes that come into play. But one thing is clear: to stay safe, we need to stop emitting as soon as possible.

Check out Ella's channel here:

Support ClimateAdam on patreon:



Do COP26 promises keep global warming below 2C?

Posted on 15 November 2021 by Zeke Hausfather, Guest Author

This is a re-post from Carbon Brief

Depending on whom you ask, the COP26 climate summit may seem like the best of times or the worst of times. 

On the one hand, reports proclaim boldly that limiting global warming to below 2C might finally be in reach. On the other, critics complain that modest improvements on country commitments amount to little more than “blah blah blah”.

The reality is more nuanced. There has been progress made in flattening the curve of future emissions through both climate policies and falling clean energy costs. At the same time, the world is still far from on track to meet Paris Agreement goals of limiting warming to 1.5C or “well below” 2C. 

COP26 negotiations have seen a flurry of new reports on what existing and new promises and pledges mean for the climate.

Here, Carbon Brief breaks down these numbers, looking at what they refer to, where different groups agree and disagree on likely outcomes, and the potential impact of new long-term net-zero promises.

The analysis reveals widespread agreement between four different groups assessing the climate outcomes of COP26. They suggest that current policies will lead to a best-estimate of around 2.6C to 2.7C warming by 2100 (with an uncertainty range of 2C to 3.6C). 

If countries meet both conditional and unconditional nationally determined contributions (NDCs) for the near-term target of 2030, projected warming by 2100 falls to 2.4C (1.8C to 3.3C).

Finally, if countries meet their long-term net-zero promises, global warming would be reduced to around 1.8C (1.4C to 2.6C) by 2100, though temperatures would likely peak around 1.9C in the middle of the century before declining.

In addition to the revised NDCs, there have been a series of announcements at COP26 – including the Global Methane Pledge and an accelerated coal phaseout, as well as business pledges as part of the Race to Zero campaign. Carbon Brief’s analysis finds that these new announcements – combined with recent updates to NDCs – have likely shaved an additional 0.1C warming off what was implied under commitments out to 2030. 

Similarly, India’s new net-zero pledge has reduced projected global temperature rise by around 0.2C – if all countries meet their long-term net-zero promises.

The extent to which the many new and revised targets will be met will depend on whether they are translated into meaningful near-term commitments. So far the lack of stronger commitments for emissions cuts by 2030 creates a “very big credibility gap” for net-zero promises, according to the Climate Action Tracker.

Being unable to bend the emission curve downwards this decade puts huge pressure on the remaining carbon budget for “keeping 1.5C alive”. Taking this pathway implies a heavy reliance on CO2 removal beyond 2030 – with its many feasibility, technological, governance and sustainability risks.



2021 SkS Weekly Climate Change & Global Warming News Roundup #46

Posted on 14 November 2021 by BaerbelW

Listing of articles linked to on the Skeptical Science Facebook Page during the past week: Sun, November 7, 2021 through Sat, November 13, 2021

The following articles sparked above average interest during the week: The Keeling Curve: What path will we take, Extreme Makeover: Human Activities Are Making Some Extreme Events More Frequent or Intense, The Keeling Curve: Monitoring our progress to Net-0, Explainer: What's the difference between 1.5°C and 2°C of global warming?, Oklahoma Proposes Letting Gas Utility Charge A $1,400 ‘Exit Fee’ To Go Electric, and Scientists extend and straighten iconic climate “hockey stick”.

Articles Linked to on Facebook



Honest Government Ad | Net Zero by 2050 (feat. Greta Thunberg)

Posted on 12 November 2021 by Guest Author

The Government™ has made an ad about Net Zero by 2050 and it’s surprisingly honest and informative.

Become a Patron:



Skeptical Science New Research for Week #45, 2021

Posted on 11 November 2021 by Doug Bostrom, Marc Kodack

If the forecast says "rain," bring an umbrella

One of the more thought-provoking articles in this week's collection is Natural hazards and climate change are not drivers of disasters, by Alik Ismail-Zadeh of Karlsruhe Institute of Technology. A provocative title, but it's hard to argue with the article's premise, let alone deny our deep and rich history of unsatisfactory outcomes thanks to not paying attention and money where both are mandatory. Dr. Ismail-Zadeh points out that when we're fully informed of risks and hazards, disasters mostly happen only when we ignore that information and fail to take it into account in our systems of communicating and living. In a manner of speaking, our behavior is disastrously oblivious. The author examines some case histories of hazards and risks inadequately folded into plans and actions, and points out specific means to redress the situation. Open access, free to read. 

More able hands on deck 

It's very pleasing to  mention that recently joined Skeptical Science volunteer Dr. Marc Kodack is providing a significant boost to compilation of New Research. We're very fortunate; Marc  is arguably "overqualified" for this particular work, given  his deep experience in the intersection of climate change and US national security. Marc is currently also (mainly?!)  a Senior Fellow at the The Center for Climate and Security.  We're delighted to welcome Marc aboard. 

82 articles by 445 contributing authors

Physical science of climate change, effects

An Analytical Model for Spatially Varying Clear-Sky CO2 Forcing
Jeevanjee et al. Journal of Climate

Temperature-dependence of the clear-sky feedback in radiative-convective equilibrium
Kluft et al. Geophysical Research Letters



Supreme Court to weigh EPA authority to regulate greenhouse pollutants

Posted on 10 November 2021 by Guest Author

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

The Supreme Court agreed to hear a case, West Virginia v. EPA, challenging the Environmental Protection Agency’s authority to regulate greenhouse gases as pollutants.

The case presents an opportunity for the Court to overturn key climate precedents and potentially change the relationship between federal agencies and Congress. The decision could have far-reaching consequences for federal climate policy and perhaps even for federal agencies more broadly.

How did we get here, how far might the Court go, and what consequences might the case have for climate change regulation and executive branch authority?

EPA’s authority to regulate greenhouse gases: Massachusetts v. EPA

In a groundbreaking decision in 2007, the Supreme Court held 5-4 that EPA has authority to regulate greenhouse gases under the Clean Air Act. During the Bush administration, environmentalists petitioned the agency to issue a rule on the regulation of greenhouse gases. The Bush EPA denied the petition, and environmental groups, states, and local governments challenged that decision in court. The Supreme Court’s decision turned on whether greenhouse gases like carbon dioxide fall under the definition of “air pollutants,” which the Clean Air Act authorizes EPA to regulate.

The Court concluded that carbon dioxide and other greenhouse gases are air pollutants under the Clean Air Act’s definition, and also noted that the EPA cannot refuse to regulate greenhouse gases for policy reasons outside the Clean Air Act itself, as the Bush administration had done. The Court ordered EPA to either issue a finding that greenhouse gases are dangerous to the public health and welfare, the first step toward regulation, or to give a reasoned explanation for why greenhouse gases do not meet the threshold of endangerment outlined in the Clean Air Act. The agency ultimately found that greenhouse gases are dangerous to the public health and welfare, which formed the foundation for EPA’s regulation of greenhouse gases.

That Supreme Court’s ruling in Massachusetts v. EPA was a 5-4 decision, and environmental advocates leading up to it were not at all certain that they would win the case. In fact, the case was controversial at the time because many environmentalists worried that it would result in a harmful adverse ruling. The four liberals on the Court in 2007, Justices Souter, Ginsburg, Breyer, and Stevens, were joined by Justice Kennedy to form a majority. But Chief Justice Roberts and Justices Thomas, Scalia, and Alito dissented.

Chief Justice Roberts’s dissent (joined by Justices Scalia, Thomas, and Alito) argued that the states, local governments, and environmental groups challenging the EPA should not have been allowed to sue in the first place because they lacked standing: One requirement of standing is a “concrete and particularized” injury. Chief Justice Roberts argued that harms from climate change affect everyone, so the injury in question was not sufficiently individualized and personal to support a lawsuit.

Justice Scalia’s dissent (joined by Chief Justice Roberts and Justices Thomas and Alito) focused on the Clean Air Act and argued that the Act is meant to address conventional air pollutants that harm human health directly through exposure, such as inhalation. He maintained that the Act was not meant to address the broader issue of climate change, and that greenhouse gases therefore did not fall under the definition of “air pollutants.”

Of course, the Supreme Court’s composition has changed significantly since 2007. With a 6-3 conservative-liberal divide, the conservative dissenters’ objections to Massachusetts v. EPA may now represent the majority view.



The Keeling Curve: Part III

Posted on 9 November 2021 by Evan

What Road Will We Take?

There is much discussion about reducing our carbon footprint to stabilize climate. Many companies pledging to become carbon neutral, some pledging to remove all of their legacy carbon emissions, one car company after another announcing new lines of sleek EV’s. We will need all of these efforts, and more, because as of 2020, the IPCC consensus is that to avoid the worst effects of GW/CC, we must achieve the following, twin objectives:

  • Become carbon-neutral (Net-0 Emissions) by 2050.
  • Maintain temperature anomalies well below 2°C.

Becoming carbon neutral is needed to stop GHGs from continuing to build up in the atmosphere and hopefully decrease atmospheric CO2 concentrations. Staying well below 2°C is needed to limit climate change to a level to which human civilization can adapt.

Are these twin goals realistic? What will it take to achieve them? If the best we can do is to achieve Net-0 Accumulation,  but not necessarily by 2050, to what level of warming will we stabilize climate? Regardless of our best intentions, there may be limits on how much we can do and how fast. Like a super-tanker plying the oceans at top speed, there are physical limits on how fast course corrections can be made. Sociological limits determine how fast we can mobilize effective action. As of 2021, none of the talk, high-level negotiations, nor even a pandemic has altered the persistent, upward trajectory of CO2 as represented by the Keeling Curve.

There are also technical and monetary issues. We know how to decarbonize the energy sector using wind, solar, battery storage, EV’s, and other current and up-and-coming technologies such as nuclear, and hopefully someday, fusion power. It will take time, but we are well on our way to doing it and low-carbon energy is already cheaper than building new fossil-fuel power plants. Decarbonizing the energy sector, however, is not sufficient to stabilize climate. We must also remove CO2 from the atmosphere to balance GHG emissions from sectors that are difficult to decarbonize, such as agriculture. Although land-use modifications are being studied as ways to increase the CO2 uptake by the biosphere, drawing down CO2 concentrations at a rate required to stabilize CO2 concentrations will likely require artificial, mechanical means as well.

Because agricultural, baseline emissions cannot be easily eliminated, they must be compensated for by using Negative Emissions Technologies (NET) to extract an equal amount of GHGs directly from the air. Estimates by Larkin et al. (2014) suggest that baseline emissions amount to about 1 ton CO2e/person/yr.1  We use this average value from Larken et al. to approximate how the baseline emissions scale with population, and the implications for the level of NET required to offset them. For the purposes of the modeling scenarios described here, we treat the non-CO2 baseline emissions as all CO2. We refer to the CO2 accumulation due to baseline emissions as Baseline Accumulation Rates (BAR).

There are three challenges to deploying NET systems at a scale sufficient to counteract human GHG emissions.



Tiny leaks, big impacts: New research points to urban indoor methane leaks

Posted on 8 November 2021 by Guest Author

This is a re-post from Yale Climate Connections by Daniel Grossman

Methane, the major component of natural gas, punches way above its weight when it comes to damaging the climate. Humans send less than half a billion tons of methane into the air every year, only one percent of the amount of carbon dioxide we spew from our cars, homes and factories. Yet methane is responsible for about 20 percent of global warming. This fact should motivate humanity to reduce our reliance on natural gas as a fuel as quickly as possible and, in the meantime, plug even small leaks in the existing natural gas system from wells to gas-burning appliances, says Marc Fischer, a scientist at Lawrence Berkeley National Laboratory.

Researchers in Boston have been studying methane leakage in urban areas for eight years and the pandemic gave them a unique natural experiment to compare methane levels during the lockdown with those from normal activity. Publication of their findings this month give ammunition to scientists who have long contended that much more gas is leaking from city sources than has been widely believed. The findings suggest also that far more natural gas is seeping out from pipes and appliances in buildings than previously thought, and that slowing global warming requires fixing these leaks as soon as possible or, possibly, phasing the fuel out faster than policy makers are planning. 

One strategy, said Maryann Sargent, a climate scientist at Harvard University and lead author of the new paper, might be to stop connecting new buildings to gas lines. “If you stop consuming, you stop emitting,” she said. “You could have more of an impact than you might think in reducing methane emissions now.”

Indoor stoves, heaters, ovens and gas-powered appliances 

For thousands of years methane generated by human endeavors has wafted into the air. Rice paddies and cattle produce it. Farming obviously still emits methane today. But the largest source now is production and distribution of natural gas (which is 90% methane) and, to a lesser extent, coal mining and oil. Natural gas usage is growing fast both in the U.S. and abroad, adding urgency to efforts to prevent leakage. Climate researchers have warned about methane leaks from gas wells, pipelines, and other fossil fuel production and transportation infrastructure. But methane emissions from urban sources in buildings – for instance, stoves, ovens, heaters, and other gas-fired appliances inside homes and business – have not been on most experts’ radar.  

A gas stove burning.



2021 SkS Weekly Climate Change & Global Warming News Roundup #45

Posted on 7 November 2021 by BaerbelW

Listing of articles linked to on the Skeptical Science Facebook Page during the past week: Sun, October 31, 2021 through Sat, November 6, 2021

The following articles sparked above average interest during the week: The Keeling Curve: Reality Check, IPCC, You’ve Made Your Point: Humans Are a Primary Cause of Climate Change, Vapor Storms Are Threatening People and Property, Top climate scientists are sceptical that nations will rein in global warming, Op-Ed: On the climate crisis, delay has become the new form of denial, COP26: Stage set for crucial climate negotiations and Discourses of Climate Delay.

Articles Linked to on Facebook



The Keeling Curve: Part II

Posted on 5 November 2021 by Evan

Monitoring our progress to Net-0

In the context of IPCC goals and company initiatives, “Net-0” means achieving the point where an entity emits no net GHGs. That entity could be a single company,1  an entire country,  or the entire Earth; the ultimate goal of the Paris Accord. Two related questions are

  • What does it mean to achieve Net-0?
  • How do we know when we’ve reached Net-0?

Deceptively simple questions with not quite so simple answers.

What does it mean to achieve Net-0?

Humans must remove from the atmosphere the same amount of CO2 that we emit. That is the meaning of Net-0. If we do this, the environment has a carbon-removal matching plan such that it will remove additional CO2 on our behalf, for free, so that if/when we reach Net-0 Emissions, atmospheric CO2 concentrations will actually start to decrease!

How cool is that. The atmosphere is ready to help out with a carbon-removal matching plan, as long as we do our part. Although no countries have yet achieved Net-0 Emissions, some companies, such as Google, claim to have already become carbon neutral, which means essentially the same thing as achieving Net-0 Emissions. But here is an important distinction.

  • Carbon free means that you don’t emit the carbon, such as by using solar and wind for electricity generation.
  • Carbon neutral means reduction of carbon emissions as much as possible, by using carbon-free technology, and then offsetting the remaining carbon emissions using methods that remove as much CO2 from the atmosphere as we emit. One practice is to buy carbon offsets, typically covered by planting trees or land restoration. Other methods include substituting for fossil fuels, biofuels made from recycled carbon.

Carbon free is what we would like, but because running completely carbon free is probably not possible, carbon neutral is needed to reach Net-0 Emissions.

A problem using trees to offset carbon emitted today is that it represents a promise to remove tomorrow what we emit today. That is, once the carbon is emitted, a significant portion will remain in the atmosphere for 1000’s of years, or until we physically remove it. That’s what trees and other carbon-removal technologies are supposed to do at some future date. However, even though we plant trees, we cannot guarantee their long-term survival nor that they will survive land-use policy changes by future administrations.

We can praise companies that make the effort to become Net-0, but even if well-intentioned marketing divisions of large corporations convince their users and shareholders that they are now a green, environmentally-responsible company, nature is not so easily convinced. And nature is the only judge of our efforts that matters. How can we monitor what nature is seeing as the sum total of our efforts to reach Net-0 status?



Skeptical Science New Research for Week #44, 2021

Posted on 4 November 2021 by Doug Bostrom

151 articles by 1,022 contributing authors

Physical science of climate change, effects

Arctic amplification of precipitation changes - the energy hypothesis
Pithan & Jung Geophysical Research Letters

Observations of climate change, effects

Evaluation of long-term air temperature, precipitation and flow rate parameters trend change using different approaches: a case study of Amik plain, Hatay
Üne? & Kaya Theoretical and Applied Climatology

(provisional link) Observed and forecasted global warming pressure on coastal hypoxia

Upslope migration of snow avalanches in a warming climate
Giacona et al. Proceedings of the National Academy of Sciences
Open Access pdf 10.1073/pnas.2107306118

Rapid Sea Level Rise in the Southern Hemisphere Subtropical Oceans
Duan et al. Journal of Climate

Possible influence of the warm pool ITCZ on compound climate extremes during the boreal summer
Basconcillo et al. Environmental Research Letters
Open Access 10.1088/1748-9326/ac30f8

One extreme fire weather event determines the extent and frequency of wildland fires
Wang et al. Environmental Research Letters
Open Access 10.1088/1748-9326/ac2f64

Response of Southern Hemisphere western boundary current regions to future zonally symmetric and asymmetric atmospheric changes
Goyal et al. Journal of Geophysical Research: Oceans
Open Access 10.1002/essoar.10507696.1

(provisional link) Slower long-term coastal warming drives dampened trends in coastal marine heatwave exposure

Interannual variability of surface salinity and Ekman pumping in the Canada Basin during summertime of 2003−2017
Dong et al. Journal of Geophysical Research: Oceans

Increased variability in Greenland Ice Sheet runoff from satellite observations
Slater et al. Nature Communications
Open Access pdf 10.1038/s41467-021-26229-4

Meteorological causes of the catastrophic rains of October/November 2019 in equatorial Africa
Nicholson et al. Global and Planetary Change

Twentieth century temperature and snow cover changes in the French Alps
Beaumet et al. Regional Environmental Change
Open Access pdf 10.1007/s10113-021-01830-x

Drivers of Global Clear Sky Surface Downwelling Longwave Irradiance Trends from 1984 through 2017
Clark et al. Geophysical Research Letters

Subglacial channels, climate warming, and increasing frequency of Alpine glacier snout collapse
Egli et al. Geophysical Research Letters

Fast local warming is the main driver of recent deoxygenation in the northern Arabian Sea
Lachkar et al. Biogeosciences
Open Access pdf 10.5194/bg-18-5831-2021

Geoscientists, Who Have Documented the Rapid and Accelerating Climate Crisis for Decades, Are Now Pleading for Immediate Collective Action
Filippelli et al. Geophysical Research Letters
Open Access 10.1029/2021gl096644

Characterizing Winter Season Severity in the Midwest United States, Part I: Climatology & Recent Trends
Ford et al. International Journal of Climatology

Instrumentation & observational methods of climate change, effects

(provisional link) A 10-year record of Arctic summer sea ice freeboard from CryoSat-2

Earth observations of extreme heat events: leveraging current capabilities to enhance heat research and action
Zaitchik & Tuholske Environmental Research Letters
Open Access 10.1088/1748-9326/ac30c0

Guidelines for studying diverse types of compound weather and climate events
Bevacqua et al. Earth's Future
Open Access pdf 10.1029/2021ef002340



Discourses of Climate Delay

Posted on 3 November 2021 by BaerbelW

This blog post combines extracts from articles published by our German language partner website, one from September 2020 and another from January 2021. It'll be the start of a series of blog posts looking more closely at the various discourses of climate delay, an insidious way to keep delaying action to combat climate change now that outright climate science denial seems to be waning.

"Discourses of Climate Delay" is the title of a study (Lamb et al. 2020), which got quite some attention upon publication. You could also call these "climate cop-outs", excuses to not having to do much against climate change. A team from the Mercator Research Institute on Global Commons and Climate Change (MCC) in Berlin had analyzed often-heard delaying arguments and put them into a taxonomy.

They found four main categories:

Redirect Responsibilities: Someone else should take action first

Propagate non-transformative solutions: Mitigate without fundamental, disruptive changes - the "not like this" excuse

Emphasize the downsides of climate policy because it would be politically and socially unjustifiable.

Surrender: stating that it's too late and that a change of course is no longer possible.

Or shorter: "Not me, not like this, not now and too late"!


Figure 1: The Discourses of Climate Delay from Lamb et al. 2020 (click image or here for larger version)



Clean energy could save American lives to tune of $700 billion per year

Posted on 2 November 2021 by dana1981

This is a re-post from Yale Climate Connections

The case for climate solutions has long been hindered because of the decades it will take for investments made today to yield benefits in the form of less extreme weather impacts. Carbon dioxide pollution remains in the atmosphere for upwards of a millennium, and so efforts to curb carbon emissions will only slowly bend the global warming curve. Clean technologies deployed today will yield significant changes in extreme weather only toward the middle of the century.

Compelling people to support climate solutions thus usually requires appealing to their better natures; to invest in protecting the future quality of life of today’s children. People often have difficulty making decisions based on such long-term considerations.

But as a new study in the Proceedings of the National Academy of Sciences (PNAS) concludes, curbing climate change does yield immediate benefits in the form of cleaner air resulting in healthier and longer lives. The paper was authored by 11 scientists from Duke and Columbia Universities and the NASA Goddard Institute for Space Studies (GISS), including lead author Drew Shindell, who has published over 250 peer-reviewed climate studies over the past 25 years, and NASA GISS Director Gavin Schmidt.

The study estimates that Americans would value the benefits of longer lives associated with cleaner air at $700 billion per year over the next two decades – a number far higher than the costs of climate solutions.

Valuing longer and healthier lives from cleaner air

In addition to pumping greenhouse gases into the atmosphere, burning fossil fuels also releases other air pollutants that create higher levels of ozone and easily respirable fine particulate matter like PM2.5. Ozone can aggravate lung diseases like asthma and emphysema, while PM2.5 can cause premature death in people with heart problems or lung disease and can also aggravate asthma. A 2018 study, also published in PNAS, has found that outdoor PM2.5 air pollution is considerably more harmful to human health than previously estimated.

Those results were incorporated into this new research, which estimates that in 2020, PM2.5 and ozone pollution caused 191,000 and 57,000 premature deaths in the U.S., respectively, compared to 17,000 heat-related deaths. Were the U.S. to follow a pathway to meet the 2015 Paris climate agreement target of limiting global warming to 2 degrees Celsius (3.6 degrees Fahrenheit) above pre-industrial temperatures, many of these premature deaths would be avoided (19% of PM2.5 and 57% of ozone deaths over the next two decades; 31% and 77% through 2070, respectively).

All told, close to 1.4 million premature American deaths would be avoided through 2040 and 4.5 million through 2070, compared to a business-as-usual pathway. And those longer lives would also be healthier as a result of people’s breathing cleaner air.



The Consensus Project Website


(free to republish)

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