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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, discourses of climate delay, and climate solutions denial.


What you need to know about record-breaking heat in the Atlantic

Posted on 29 May 2024 by Guest Author

This is a re-post from Yale Climate Connections by Michael Lowry

map showing record warm temperatures in the CaribbeanOver 90% of the tropical Atlantic is experiencing record or near-record warm sea surface temperatures for late May.

Waters across the Atlantic’s tropical belt — extending from the coast of Africa through the Caribbean — are hotter now than in any other late May on record, with over 90% of the area’s sea surface engulfed in record or near-record warmth. The extent of marine heat has never been greater heading into a hurricane season, outpacing by wide margins the previous late May record-holder in 2005, a year remembered for one of the most active and destructive hurricane seasons in modern history.

About 67% of the tropical Atlantic experienced record or near-record warm sea surface temperature anomalies in late May 2005 using 1981-2024 records, a notably smaller extent than May 2024. The Atlantic Main Development Region (area outlined by the black boxes above) is the warmest on record (since 1981) going into a hurricane season.

Although record-setting sea surface temperatures alone don’t guarantee a busy hurricane season, they do strongly influence it, especially when the abnormal warmth coincides with the tropical belt known as the Main Development Region, or MDR, the area where 85% of Category 3, 4, and 5 hurricanes form. When considered alongside a developing La Niña — the periodic cooling of the equatorial Pacific that reduces storm-busting Atlantic wind shear — the unprecedented ocean heat is driving up seasonal hurricane outlooks higher than ever before.

Colorado State University — the group that pioneered seasonal hurricane forecasts in the 1980s — issued its most aggressive April forecast last month in almost 30 years of doing such preseason outlooks. NOAA, the parent agency of the National Weather Service, will release its first 2024 hurricane season outlook May 23, and expectations are for similarly bullish numbers.



At a glance - What is the link between hurricanes and global warming?

Posted on 28 May 2024 by John Mason, BaerbelW, Ken Rice

On February 14, 2023 we announced our Rebuttal Update Project. This included an ask for feedback about the added "At a glance" section in the updated basic rebuttal versions. This weekly blog post series highlights this new section of one of the updated basic rebuttal versions and serves as a "bump" for our ask. This week features "What is the link between hurricanes and global warming?". More will follow in the upcoming weeks. Please follow the Further Reading link at the bottom to read the full rebuttal and to join the discussion in the comment thread there.


At a glance

Hurricanes, Cyclones or Typhoons. These are traditional terms for near-identical weather-systems. The furious storms that affect the tropics have a fearsome reputation for the havoc they bring. Such storms are driven by the heat of the tropical oceans, where sea surface temperatures vary by just a few degrees Celsius and are almost always in the high twenties. Hurricane formation can only take place at such temperatures.

In the Atlantic, for example, a tropical storm-system begins life as a developing wave of low pressure tracking westwards out of Africa. Offshore in the tropical Atlantic, the warmth of the ocean's surface drives intense evaporation. That warmth and moisture provide the fuel for thunderstorm development.

Most such waves simply carry clusters of disorganised showers and thunderstorms. But in some, the storms organise into rain-bands. Once that happens, low-level warm and moist air floods in towards the low pressure centre from all compass points. But it does so in an inward spiralling motion. Why? That's due to the Coriolis Effect. Because the Earth rotates, circulating air is deflected to the right in the Northern Hemisphere, resulting in a curved path. In the Southern Hemisphere the air is deflected to the left. The effect is named after the French mathematician Gaspard Gustave de Coriolis (1792-1843), who studied energy transfer in rotating mechanical systems, such as waterwheels.

The other essential ingredient required to form and keep a hurricane going is low wind shear. Wind shear is defined as winds blowing at different speeds and in different directions at different heights in the Troposphere - the lower part of our atmosphere where weather occurs. For a hurricane, wind-shear of less than 10 knots from the surface to the high troposphere is perfect.

With those ingredients in place, an organised cluster of thunderstorms may spin up into a tropical depression. If conditions favour further development, a tropical storm will form and then strengthen into a hurricane. A hurricane has a minimum constant wind speed of 119 kilometres per hour (74 mph). The most intense Category 5 storms have sustained winds of more than 252 kilometres per hour (157 mph). Highest winds are typically concentrated around the inner rainbands that surround the hurricane's eye.

So, given the above, what will a warmer world result in?

It's a bit of a mixture due to the number of variables involved. The number of storms reaching Category 3-5 intensity is considered to have increased over recent decades. That's because warmer sea surface temperatures give a storm more fuel. In contrast, the number of individual systems in a given year appears to have decreased although the jury's still out on that. But one thing is a lot more certain. Extreme rainfalls.

There's a simple, memorable formula that describes how warmer air can carry more moisture: 7% more moisture per degree Celsius of temperature increase. Hurricanes already dump vast amounts of rain: in a warmer world that amount will only increase. Allowing further warming to take place simply makes an already bad situation worse.

Please use this form to provide feedback about this new "At a glance" section. Read a more technical version below or dig deeper via the tabs above!

Click for Further details



The silent tragedy of local restrictions on renewable energy

Posted on 27 May 2024 by Guest Author

This story by James Goodwin was originally published by The Revelator and is part of Covering Climate Now, a global journalism collaboration strengthening coverage of the climate story.

Communities across the United States may soon find themselves facing a grim scenario. By adopted local ordinances that obstruct the development of new renewable energy resources within their borders, they have put themselves at risk of missing out on the next big technology-driven economic revolution: the clean energy transition.

As you read this, rapidly advancing renewable energy technology is transforming how we power the U.S. economy in the 21st century, bringing with it new economic opportunities and social and environmental benefits. Yet the communities that have enacted or are considering anti-renewable energy ordinances may be left watching as the better jobs, cheaper electricity, and cleaner environment that come with this transition pass them by.

Many of these communities already face high unemployment and poverty rates, among other economic and social challenges, making the consequences of their legislation even more tragic.

The press and energy policy researchers have focused on these policies’ potential impact on achieving our nation’s broader decarbonization goals, but to date they’ve overlooked these broader consequences of anti-renewable energy ordinances.

It’s crucial that we closely watch how the benefits and costs of the clean energy transition are distributed, because previous technology-driven economic revolutions — such as those brought about by steam engines, electrification, and digital computers — have tended to reinforce preexisting socioeconomic inequities. The clean energy transition offers a critical opportunity not just to break this pattern, but to reverse it.

Can we imagine the clean energy transition unfolding in a way that reduces inequality?



2024 SkS Weekly Climate Change & Global Warming News Roundup #21

Posted on 26 May 2024 by BaerbelW, Doug Bostrom, John Hartz

A listing of 34 news and opinion articles we found interesting and shared on social media during the past week: Sun, May 19, 2024 thru Sat, May 25, 2024.

Story of the week

This week's typiclal compendium of stories we'd rather were plot devices in science ficition novels but instead are captured from our own small planet present a daunting prospect. We're in a world of trouble, documented day-by-day. Is there a unifying theme to our troubles, and if so what's our answer?

How about looking for a theme?

That's 10 of 34 stories we highlight this week. Granted this is colored by Skeptical Science's own prism, which is concerned with climate change as a communications challenge thwarted by vested interests.. That said, the litany of physical, biological and cultural impacts of our accidental sudden changing of our climate clearly share a common root cause: fossil fuel extraction and marketing at prodigious scale. 

Nobody originally intended or volunteered to cause harm on the scale of our anthropogenic climate change, but equally we shouldn't expect any volunteers to step forward to abandon what's worked before in terms of acquiring wealth in astronomical quantity. Let alone gratuitously eschewing vast riches, the entrenched fossil hydrocarbon industry is actively working to preserve the earning capacity of its natural gift-- including by promoting copious bunk (pdf) for absorption by the public mind. We can gauge the success of this strategy by our current global temperature. Climate disinformation works at scale.  

All of this by way of elliptically arriving at our Story of the WeekMastering FLICC - A Cranky Uncle themed quizRarely we blow our own horn— that's what you're hearing now. What's "FLICC?" FLICC stands for "Fake experts," "Logical fallaices," "Impossible expectations,' "Cherry picking," and "Conspiracy theories." FLICC is a taxonomical system for classifying different forms of bunk, allowing us to identify which particular cognitive weapons are being targeted at our psychological susceptibilities. Here we're talking about climate disinformation promoted by the fossil fuel industry.

Some familiarity and practice with FLICC helps us to deal with the firehose of climate myths lobbed into our brains by professional disinformers on a daily basis. Our Story of the Week is really a quiz: How are your bunk detection skills right now? Take our test and find out. If you're not happy with your results, give our FLICC synopsis a read! 

Stories we promoted this week, by publication date:

Before May 19

May 19

May 20



Mastering FLICC - A Cranky Uncle themed quiz

Posted on 24 May 2024 by BaerbelW

By now, most of you will have heard about the FLICC taxonomy of science denial techniques and how you can train your skills in detecting them with the Cranky Uncle game. If you like to quickly check how good you are at this already, answer the 12 quiz questions in the form below. The form is not collecting any personal information but it contains a comment field at the end in case you'd like to give some feedback.

If you need a cheat-sheet with all the fallacy definitions you can open or download a PDF here. The quiz is also available for download as a PDF slide-deck. Please let us know via our contact form if you'd like to have it as a PPTX-file to include in your own presentations.

Quiz Time!



Skeptical Science New Research for Week #21 2024

Posted on 23 May 2024 by Doug Bostrom, Marc Kodack

Open access notables

How much storage do we need in a fully electrified future? A critical review of the assumptions on which this question depends, Marsden et al., Energy Research & Social Science:

Our analysis advances the argument that current approaches reproduce interpretations of normality that are, ironically, rooted in an era of fossil fuels. This has the perverse effect of reproducing present standards and modes of living and perpetuating ultimately unsustainable routines and expectations. We argue that the way out of this impasse is to invite more open discussion about the social worlds implicit in contemporary scenarios and forecasts. Rather than thinking about the types of storage needed to preserve the status quo, the challenge is to imagine the temporal, spatial and organisational qualities of energy systems, including systems of storage, that might be compatible with much lower carbon ways of life, and with very different patterns and levels of demand.

“These industries have polluted consciences; we are unable to envision change“: Sense of place and lock-in mechanisms in Sulcis coal and carbon-intensive region, Italy, Biddau et al., Global Environmental Change

The study focuses on Sulcis CCIR (Sardinia, Italy), where extractive and metal industries are deeply ingrained in the region's culture and economy. To reconstruct the trajectory of the CCIR and gain in depth understanding of feedback mechanisms of path dependency across time, we triangulate different data sources including policy documents, newspapers, participatory workshops, and interviews with key stakeholders. The findings reveal the profound influence of a sense of place grounded in a shared industrial myth along with associated place meanings, identities, and memories on lock-in mechanisms. Positive feedback loops between sense of place and structural factors of lock-in have legitimated the dominance of coal and carbon-intensive industries across time, impeding the recognition of the need for change and obscuring windows of opportunity for low-carbon transformation.  

When enough is enough: Introducing sufficiency corridors to put techno-economism in its place, Bärnthaler, Ambio

Recognising the limitations of techno-economism, focused on markets (price adjustments) and technology (efficiency gains), this contribution introduces sufficiency corridors as a concept, research field, and policy approach. Sufficiency corridors represent the space between a floor of meeting needs and a ceiling of ungeneralisable excess, i.e. within the sufficiency corridor everyone has enough (to satisfy needs) while no one has too much (to endanger planetary boundaries and need satisfaction). Establishing such corridors entails a process over time that continuously narrows the gap between floors and ceilings, lifting the former and pushing down the latter by strengthening forms of consumption and production that contribute to need satisfaction while shrinking those that do not. 

One Day When We Were Young: Nostalgia Brings Climate Change Temporally Closer, Huang et al., Environmental Communication

The perceived temporal distance of climate change impacts has been considered a long-standing barrier to climate engagement. Because nostalgia has distinct cognitive properties related to temporal thinking, three experimental studies are conducted to investigate nostalgia's potential for shortening temporal distance. Study 1 shows that nostalgia increases climate engagement by reducing temporal distance. Study 2 further identifies vivid imagery as a mechanism for the nostalgia effects across US and Chinese samples. Study 3 shows that nostalgic public service announcements increase climate engagement more than non-nostalgic ones. This study provides strong evidence that evoking nostalgia can be a useful climate change communication strategy.

From this week's government/NGO section:

Fuelling Denial: The climate change reactionary movement and Swedish far-right mediaKjell Vowles, Chalmers University:

The fossil fuel industry has a long history of spreading disinformation about climate change science and obstructing mitigating policies. During the 2010s and 2020s, these vested interests have found a political ally in parts of the European far-right. This study explores how this has taken shape in Sweden, a country where there has been a political consensus about the seriousness of climate change. The ascendance of the far-right, however, has led to this consensus breaking down.

Hitting the brakes: how the energy transition could decelerate in the USDavid Brown, Wood MacKenzie:

A victory for former President Donald Trump in the election in November would mean new policy priorities and an immediate deceleration in support of decarbonization. Incentives for electric vehicle (EV) sales would likely be cut, while the growth of green hydrogen and carbon capture, utilization, and storage (CCUS) could falter. At the same time, unabated fossil generation would expand. The economic nationalism that has defined both the Trump and Biden administrations would continue. Companies could be less likely to invest in emerging technologies. These steps would push the US even further away from a net zero emissions pathway. The author explores the impact of government policy, consumer choices and the competitiveness of emerging technologies on the future of U.S. energy investment. In the delayed transition scenario, the author projects about US$6.5 trillion in investment for the U.S. energy sector over 2023-50, about 55% lower than in our net-zero scenario.

143 articles in 67 journals by 886 contributing authors

Physical science of climate change, effects

A likely role for stratification in long-term changes of the global ocean tides, Opel et al., Communications Earth & Environment Open Access pdf 10.1038/s43247-024-01432-5

Atmospheric destabilization leads to Arctic Ocean winter surface wind intensification, Zapponini & Goessling, Communications Earth & Environment Open Access pdf 10.1038/s43247-024-01428-1

Observations of climate change, effects

Metal mobilization from thawing permafrost to aquatic ecosystems is driving rusting of Arctic streams, O’Donnell et al., Communications Earth & Environment Open Access pdf 10.1038/s43247-024-01446-z

Quantifying Contributions of External Forcing and Internal Variability to Arctic Warming During 1900–2021, Chen & Dai, Earth's Future Open Access pdf 10.1029/2023ef003734

Steady threefold Arctic amplification of externally forced warming masked by natural variability, Zhou et al., Nature Geoscience 10.1038/s41561-024-01441-1

Trends in temperature and precipitation at high and low elevations in the main mountain ranges of the Iberian Peninsula (1894–2020): The Sierra Nevada and the Pyrenees, Sigro et al., International Journal of Climatology Open Access pdf 10.1002/joc.8487



Climate Adam: Can we really suck up Carbon Dioxide?

Posted on 22 May 2024 by Guest Author, BaerbelW

This video includes conclusions of the creator climate scientist Dr. Adam Levy. It is presented to our readers as an informed perspective. Please see video description for references (if any).

Is carbon dioxide removal - aka "negative emissions" - going to save us from climate change? Or is it just a dangerous distraction from the action we need - cutting fossil fuels and building renewables? The truth is somewhere in between - we're going to need to remove some amounts of carbon dioxide, but we can't rely on negative emissions to solve all our climate change problems. So what are the technologies behind the headlines, and what do they mean for our future?

Support ClimateAdam on patreon:



At a glance - How does the Medieval Warm Period compare to current global temperatures?

Posted on 21 May 2024 by John Mason, BaerbelW, Ken Rice

On February 14, 2023 we announced our Rebuttal Update Project. This included an ask for feedback about the added "At a glance" section in the updated basic rebuttal versions. This weekly blog post series highlights this new section of one of the updated basic rebuttal versions and serves as a "bump" for our ask. This week features "How does the Medieval Warm Period compare to current global temperatures?". More will follow in the upcoming weeks. Please follow the Further Reading link at the bottom to read the full rebuttal and to join the discussion in the comment thread there.


At a glance

To explore this topic, the first question must surely be: what was the Medieval Warm Period? The answer lies in the dim and distant past, in modern human terms, that is. Compared to the age of the Earth, at 4.5 billion years, it is a fraction of a very small fraction of a blink of the eye. Nevertheless, let's continue.

The period of time known to archaeologists as the Common Era (CE) roughly covers the past 2000 years. Decades ago it was divided into a series of climate epochs. Although there is no firm consensus regarding their precise duration, the 'Roman Warm Period' covered the first few centuries. The 'Dark Ages Cold Period' was from around 400-800 CE, the 'Medieval Warm Period' was from 800-1200 CE and the 'Little Ice-Age' was from 1200-1850 CE.

Each of these climatic epochs has its origin in old pieces of paleoclimatic evidence from the Northern Hemisphere. Decades ago, it was assumed each such epoch must have been global in extent. But since that time, climatology has steadily moved on. More new ways of reconstructing the Common Era climate have been discovered and refined. Coverage has been extended from those few Northern Hemisphere localities to the entire globe.

Thanks to such improvements, we now know that many of these warming and cooling events were regional, not global effects. The evidence no longer supports the idea of epochs of globally coherent and synchronous climate. Yes it was warm in Europe in the Medieval Warm Period. However, it was much cooler, for example, over the Pacific than it is today.

The coldest epoch of the last millennium is known as the Little Ice Age. But here too, the effects were not the same everywhere at the same time, as pointed out in a recent paper published in Nature. Its authors commented that peak cold occurred at widely-spaced locations hundreds of years apart. Coldest temperatures occurred during the fifteenth century in the central and eastern Pacific Ocean. But by the seventeenth century it was coldest in northwestern Europe and southeastern North America.

In contrast the same study found that the warmest period of the past two millennia occurred during the 20th century. The warmth affects more than 98% of the globe. That constitutes solid evidence that modern human-caused global warming is unusual. As the paper says, it is, "unparalleled in terms of absolute temperatures and also unprecedented in global coverage within the past 2,000 years".

Please use this form to provide feedback about this new "At a glance" section. Read a more technical version below or dig deeper via the tabs above!

Click for Further details



Climate change is affecting mental health literally everywhere

Posted on 20 May 2024 by Guest Author

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

Farmers who can’t sleep, worrying they’ll lose everything amid increasing drought. Youth struggling with depression over a future that feels hopeless. Indigenous people grief-stricken over devastated ecosystems. For all these people and more, climate change is taking a clear toll on mental health — in every part of the world.  

Experts shared these examples and others during a recent summit organized by the Connecting Climate Minds network that brought together hundreds of scientists, doctors, community leaders, and other experts from dozens of countries who have spent the past year studying how climate change is harming mental health in their regions. 

Although mental illnesses are often viewed as an individual problem, the experts made clear that climate change is contributing to mental health challenges everywhere. 

The Connecting Climate Minds youth ambassador from Borneo, Jhonatan Yuditya Pratama, said his Indigenous community views nature as a sacred extension of being. Seeing the devastation of climate change on ancestral lands has brought his community “a profound sense of grief and loss,” he said.

“For us, mental health isn’t just about individuals,” he said. “It’s about the collective well-being of our communities and the land itself. When nature suffers, so do we.”  



2024 SkS Weekly Climate Change & Global Warming News Roundup #20

Posted on 19 May 2024 by BaerbelW, Doug Bostrom, John Hartz

A listing of 34 news and opinion articles we found interesting and shared on social media during the past week: Sun, May 12, 2024 thru Sat, May 18, 2024.

Story of the weekDeSantis

“The legislation I signed today [will] keep windmills off our beaches, gas in our tanks, and China out of our state." — Ron DeSantis, conflating geopolitics and consumer choices with anthropogenic climate change.

Thanks to it being about fake skepticism, our story of the week concerns Florida Governor Ron DeSantis and his efforts aided by the Florida state legislature to purge Florida's government of the entire concept of human-caused climate change and the inevitable public policy replies dictated by our clumsy, too-rapid disruption of Earth's more typical climate dithering. Coverage includes:

Governor DeSantis joins a small cadre of other elite, empowered cranks who've walked broadly similar paths. Picking on the most notorious person previously afforded the opportunity to attempt conjuring reality out of existence at the highest levels of access, we may ask a question. Who leaves a more lasting impact on our planet by confusing political ideology with scientific knowledge, Joseph Stalin's protege Trofim Lysenko, or Ron DeSantis? The two share a flaw— dictating politically acceptable understanding of matters connected to science even when doing so requires science denial— but whose impact endures the longest? 

By commingling political ideology with science, Lysenko caused acutely disastrous effects on agriculture in his country. However, Lysenko's drastic sway over the USSR's scientific community was fairly narrowly confined in both scope and time. After his ascent to prominence in the 1930s, Lysenko's star was rapidly fading a mere 30 years later. Mass starvation thanks to pseudoscientific practices and liquidations of "wrong-thinking" Mendelian geneticists quietly ended and now appear as relatively small features of the USSR's huge history. Lysenko's longest shadow ended up cast on scientific progress never realized thanks to his critics in academia having a tendency to end up dead or imprisoned. 

Rather than erupting from the scientific establishment as with Lysenko, Governor DeSantis emerged from the world of law and he's also playing a role less directly and immediately lethal to residents of Florida and scientists practicing there. But to the extent that it is successful, DeSantis' legislative accomplishment is similar to Lysenko's. It prohibits fully truthful and useful discussion and acknowledgement of climate science in public policy. To ban the term "climate change" in law and policy is fundamentally a denial of the existence of useful scientific knowledge. As with Lysenko's preposterous but mandatory omissions of true and useful understanding of plant genetics in the former USSR, this will have powerful ripple effects.

From a local perspective, Florida is unusually threatened by multiple aspects of climate change. It's safe to say that any friction applied to Florida's governmental response to these challenges will come at cost to residents of Florida. For instance, the state is already facing a dire insurance problem in connection with intensifying precipitation and rising sea level. It's fair to ask how DeSantis' theatrical stance addresses this conundrum. It truthfully can't, because the legislation's entire point is to avoid and prohibit mentioning "climate change." Meanwhile banned wind turbines, the cost of gas at the pump roughly tracking inflation over the years and Chinese communists hiding beneath our beds have nothing to do with Florida's property insurance problems, which are all about climate change. Governor DeSantis' proudly-signed HB 1645 is what a reasonable person might describe as functionally useless legislation in terms of helping Floridians deal with burgeoning real-world climate problems. 

We don't have the capacity to fully model the larger and longer effects of Florida's law attempting to deny the existence of some fairly basic physics. What we can say is that every procrastination over reducing our CO2 emissions will have a very long tail of effects and expense. The longer we delay modernizing our energy systems, the longer we'll see otherwise avoidable sea level rise, destructive meteorological effects, ecological failures— and needless suffering inflicted on people in Florida and far beyond. A single US state governor isn't determinative of the future of the planet, but much more than most of us such a person can exert more influence on our net outcome in dealing with the climate challenge we've created. By impeding Florida's climate mitigation public policy response, Governor DeSantis is casting a very long shadow on history— effects that with more perfect instrumentation we'd be able to measure— and seems to easily put Stalin's pet pseudoscientist Lysenko in the shade. 

Stories we promoted this week, by publication date:

Before May 12



Fact Brief - Does breathing contribute to CO2 buildup in the atmosphere?

Posted on 18 May 2024 by SkS-Team

FactBriefSkeptical Science is partnering with Gigafact to produce fact briefs — bite-sized fact checks of trending claims. This fact brief was written by Sue Bin Park in collaboration with members from our Skeptical Science team. You can submit claims you think need checking via the tipline.

Does breathing contribute to CO2 buildup in the atmosphere?

noThe CO2 we breathe is part of a balanced carbon exchange between the air and the earth. In contrast, burning fossil fuels injects CO2 into the atmosphere that has been stored underground for millions of years, causing a rapid buildup.

Fast cycling of carbon is seasonal. CO2 increases in colder months when plants decay and release their carbon. In the warmer months, CO2 decreases as plants take it in, along with sunlight, to produce energy and oxygen. Animals — including humans — eat plants, breathe in oxygen, and exhale CO2. Graphs of CO2 show a wave pattern reflecting this seasonal change.

Fossil fuels are part of the slow carbon cycle that operates over geological timescales. Burning fossil fuels takes carbon stored in the slow cycle and introduces it into the fast one. This activity is unique in Earth’s history; no other life-form has done anything on the same scale.

Go to full rebuttal on Skeptical Science or to the fact brief on Gigafact

This fact brief is responsive to conversations such as this one.


MIT Climate Portal Does the carbon dioxide that humans breathe out contribute to climate change?

US San Diego The Keeling Curve

McGill University Office for Science and Society Why isn't the carbon dioxide from breathing a concern for global warming?



Skeptical Science New Research for Week #20 2024

Posted on 16 May 2024 by Doug Bostrom, Marc Kodack

Open access notables

Publicly expressed climate scepticism is greatest in regions with high CO2 emissions, Pearson et al., Climatic Change:

We analysed a recently released corpus of climate-related tweets to examine the macro-level factors associated with public declarations of climate change scepticism. Analyses of over 2 million geo-located tweets in the U.S. showed that climate scepticism – and the aggressiveness of climate-related tweets – was greater in states with higher per capita carbon emissions. This pattern remained significant after controlling for political conservatism, GDP per capita, education, and gender, and was replicated across 126 nations from around the world. The findings are consistent with a vested interest hypothesis—misinformation around climate change is most likely to be distributed in regions where there is high fossil fuel reliance, and where the economic stakes of acknowledging climate change are high. 

Climate coalitions and anti-coalitions: Lobbying across state legislatures in the United States, Hall et al., Energy Research & Social Science:

We ask: Who are the main actors in state-level climate disputes, and what coalitions emerge as they take positions on specific areas of clean energy policy? Who wins in these contests? We built a novel dataset of interest groups' policy positions encompassing 224,530 lobbying and testimony records on 5449 pieces of legislation in 12 states. These data were supplemented with issue area categorizations for bills and organization type categorizations for interest groups. We find patterns relating the structure of support and opposition for climate policy to party control of the legislature, the amount of fossil fuel production, and the nature of utility regulation in each state. We then characterize the policy preferences of several major industries active in these arenas. 

“An island on the edge of Europe”: A study on academic air travel in Finland through a combined model of practice, Ahonen & Rask, Environmental Science & Policy:

Our findings highlight that the core elements of academic air travel in the institution we studied are physical events, social interaction, technologies, and environmental values. Although virtual alternatives and slow travel are gaining momentum, more support is needed to replace the informal interactions associated with physical presence. In addition, the external pressure to travel, e.g., to undertake fieldwork or attend conferences, is limiting efforts toward low-carbon travel. We hypothesize that change is particularly difficult to induce with linkages between various levels of society. 

The cascading effects of climate change on children: extreme floods, family mobility and child well-being in Amazonia, de Carvalho, Climate and Development;

This paper reflects on the less visible dimensions of children’s climate risk by examining a burgeoning trend of seasonal migration in Amazonia’s floodplains. Combining in-depth participant observation and draw-and-tell interviews with children, the paper focuses on identifying the different factors that shape children’s diverse experiences of flood impacts. The article examines how age and gender shape decisions around family mobility, and how different patterns of economic migration affect children left behind. The findings reveal that climate change is eroding vital social networks for children and exposing them to material and emotional hardship. 

 From this week's government/NGO section

Colorado's Double AgentsJames Browning and Trevor Culhane, F Minus and the Climate Development Lab:

Despite the climate crisis and Colorado’s worsening air quality, a package of anti-smog bills in the state legislature is facing stiff opposition from fossil fuel lobbyists. The authors find that many of these lobbyists also represent local governments, health care organizations, and other clients who are being harmed by air pollution. Th authors explore the extent to which these lobbyists are “double agents” working for fossil fuel clients at the same time they are working for victims of the climate crisis–and in some cases, even lobbying for and against the same environmental bill at the same time on behalf of different clients. 

What is Preventing Individual Climate Action? Impact Awareness and Perceived Difficulties in Changing Transport and Food BehaviourTimmons et al., Economic and Social Research Institute (ESRI):

Mitigating climate change requires large and, by historical standards, rapid changes to policy, business processes, and individual behaviour. The authors examine awareness of and perceived difficulty with individual behaviour change concerning two actions associated with high levels of emissions: transport and food choice. A nationally (Ireland) representative sample of 1,200 adults completed an online study about everyday transport and food behaviour, run in September 2023. After completing a diary task about the previous day, participants identified the parts of their day that mattered most for their carbon footprint. Answers were elicited via incentivized, open-text questions to prevent pre-set options from biasing responses. Participants also answered standard survey questions about their use of various modes of transport in a typical week and their consumption of various foods. Participants who reported wanting to change their transport behaviour and diet ‘to reduce their carbon footprint’ (47 percent and 42 percent, respectively) listed reasons why it is difficult for them to do so, again via open-text questions.

127 articles in 48 journals by 692 contributing authors

Physical science of climate change, effects

Arctic amplification-induced intensification of planetary wave modulational instability: A simplified theory of enhanced large-scale waviness, Luo et al., Quarterly Journal of the Royal Meteorological Society 10.1002/qj.4740

CO2-Dependence of Longwave Clear-Sky Feedback Is Sensitive to Temperature, Xu & Koll, Geophysical Research Letters Open Access pdf 10.1029/2024gl108259

Emerging Influence of Enhanced Greenland Melting on Boundary Currents and Deep Convection Regimes in the Labrador and Irminger Seas, Schiller?Weiss et al., Geophysical Research Letters Open Access 10.1029/2024gl109022

The relationship between elevation-dependent warming and long-term trend of surface air temperature lapse rate, Qin et al., Atmospheric Research 10.1016/j.atmosres.2024.107478



Drought fuels wildfire concerns as Canada braces for another intense summer

Posted on 15 May 2024 by Guest Author

This is a re-post from Yale Climate Connections by Gaye Taylor

As widespread drought raises expectations for a repeat of last year’s ferocious wildfire season, response teams across Canada are grappling with the rapidly changing face of fire in a warming climate.

No longer quenched by winter, nor quelled by the relative cool of night, last summer’s wildfires burned an unprecedented 18.5 million hectares of land—more than seven times the historic average.

Canada’s warmest ever winter followed, with low to non-existent snowpack in many areas, and ongoing drought raising fears that this summer will see more of Canada’s forests and wildland urban interface go up in flames.

“The dry and historically warm winter we just experienced across Canada puts the country in a bad spot heading into wildfire season over the weeks and months ahead,” The Weather Network reported in March.

In April, Canada’s Drought Monitor found much of western Canada, swathes of the Northwest Territories, central Ontario, and much of northeastern Quebec and Labrador in moderate to severe drought conditions. Meanwhile, British Columbia and Alberta are experiencing extreme and “exceptional” drought in pockets. B.C.’s scant snowpack after spring snow was at 63% of normal levels in early April, with conditions in some regions far worse, reports CBC News.

What happens next depends upon how spring progresses.

While B.C.’s south coast and interior did receive much-needed rain this past weekend and snow at higher elevations, The Weather Network predicted that any precipitation would “fall far short of what we need to meaningfully put a dent in the drought.”

Meanwhile, Alberta is now in Stage Four of its five-stage water shortage management response plan, writes Calgary City News, with 51 water shortage advisories now in effect in the province.

In Eastern Canada, the federal government warned that southern Quebec and eastern Ontario stood at a “higher than usual likelihood of fire in April,” with risks expected to extend into May, and the summer outlook dependent on whether and how much it rains.



At a glance - What ended the Little ice Age?

Posted on 14 May 2024 by John Mason, BaerbelW, Ken Rice

On February 14, 2023 we announced our Rebuttal Update Project. This included an ask for feedback about the added "At a glance" section in the updated basic rebuttal versions. This weekly blog post series highlights this new section of one of the updated basic rebuttal versions and serves as a "bump" for our ask. This week features "What ended the Little Ice Age?". More will follow in the upcoming weeks. Please follow the Further Reading link at the bottom to read the full rebuttal and to join the discussion in the comment thread there.


At a glance

Where were you in 2009? It seems an age ago now. Climate science denial was everywhere. Skeptical Science was just two years old. It was like whack-a-mole - as one myth was dealt with, more would pop up.

Among the talking-points emerging around that time was the one that global warming was simply the planet recovering from the Little Ice Age (LIA). The LIA was a period of regionally cold conditions, usually said to have occurred between 1350 and 1850. Glaciers in the European Alps reversed their decline and advanced. In London, UK, the tidal Thames froze over sufficiently for 'frost-fairs' to be held on the ice, between 1608 and 1814. Their frequency is often exaggerated; roughly one winter in ten would be a realistic estimate.

Why was it so cold? Here, time travel would be wonderful. In the absence of that, we have had to develop more ingenious ways of reconstructing what happened.

A key factor is the LIA's regional nature. Its most dramatic effects were in Europe and North America. That suggests there was an element of 'internal climate variability' involved. The latter term refers to how heat is moved around within Earth's climate system, as opposed to being added to or removed from it.

During the LIA there were 'external forcing' factors too - these are things that do add or remove heat from the climate system. There was an extended period of minimal Solar activity, known as the Maunder Minimum. However, the Maunder Minimum took place between 1637 and 1719, more than 200 years into the LIA. It cannot have caused the initial cooling.

There were several colossal volcanic eruptions during the LIA, such as Laki in 1783 and Tambora in 1815. The Samalas eruption on the Indonesian island of Lombok was also huge, but occurred in 1257, almost a century before the LIA started. Volcanogenic cooling episodes typically last just a few years, but they wouldn't have helped: Laki and Tambora likely prolonged the cold conditions.

Recent research is instead hinting that the LIA was triggered by a dramatic weakening of the Gulf Stream. That was caused by warm ocean currents penetrating far into the Arctic, causing a dramatic breakup of the sea-ice. Resultant ice-floes were 'exported' en-masse out into the North Atlantic, where they melted, generating cool freshwater. This process peaked around the year 1350. The overloading by all that cool freshwater disrupted ocean circulation patterns and a rapid regional cooling followed.

At the other end of the LIA, what warmed things back up? Firstly, the 1850 end-date is not necessarily reflected in temperature datasets. These show a steady warming trend that only emerged after 1910, steepening and becoming less interrupted after 1970. That is not a regional but global pattern, suggesting that unlike the LIA, an external forcing was dominant. There's one obvious one - our pumping out of greenhouse gases.

The year 2009 was full of predictions from well-known deniers that we were entering a cooling trend. Fourteen years on, there's no sign of that!

Please use this form to provide feedback about this new "At a glance" section. Read a more technical version below or dig deeper via the tabs above!

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Climate change is making hurricanes more destructive

Posted on 13 May 2024 by Guest Author

This is a re-post from the Climate Brink by Andrew Dessler

Because hurricanes are one of the big-ticket weather disasters that humanity has to face, climate misinformers spend a lot of effort muddying the waters on whether climate change is making hurricanes more damaging.

With the official start to the hurricane season in the North Atlantic coming up (June 1), I figured it was time to explain why we can be so confident that hurricanes are indeed more destructive today due to climate change.

Note: from here on out, I’ll refer to hurricanes as tropical cyclones (abbreviated TCs), which is a more general term for this type of storm.

1. Tropical cyclones are becoming more destructive: sea level

We have 100% confidence that sea level is rising because humans are heating the planet. And higher sea levels mean today’s TCs do more damage than an identical tropical cyclone in a cooler climate because the storm surge is riding on a higher sea level.

As Prof. Adam Sobel said in Congressional testimony a few years ago:

The most certain way in which hurricane risk is increasing due to climate is that, because of sea level rise, coastal flooding due to hurricane storm surge is becoming worse. Storm surge occurs when the winds from a storm push the ocean onto the land. The total flooding is determined by the surge (the part produced by the wind), the tide, and the background average sea level. As sea level has risen … the flooding is exacerbated by that amount.

Climate misinformers will respond that sea level only contributes a small fraction to the total flood depth. But the non-linearity of flood damages means that even a small contribution from sea level rise to total flood depth can increase damages a lot.

North Miami, Fla., is one of the cities on the U.S. East Coast with sea level rise well above the global average.



2024 SkS Weekly Climate Change & Global Warming News Roundup #19

Posted on 12 May 2024 by BaerbelW, Doug Bostrom, John Hartz

A listing of 35 news and opinion articles we found interesting and shared on social media during the past week: Sun, May 5, 2024 thru Sat, May 11, 2024.

(Unfortunate) Story of the week

"Grief that stops at despair is an ending that I and many others, most notably those on the frontlines, are not prepared to accept." — Dr. Christiana Figueres

Our Story of the Week concerns what can be termed a gut check survey of climate scientists commissioned by The Guardian newspaper, World’s top climate scientists expect global heating to blast past 1.5C target. With nearly half of all IPCC lead authors and review editors responding, this highly informed body of opinion tabulated unfavorably:

Almost 80% of the respondents, all from the authoritative Intergovernmental Panel on Climate Change (IPCC), foresee at least 2.5C of global heating, while almost half anticipate at least 3C (5.4F). Only 6% thought the internationally agreed 1.5C (2.7F) limit would be met.

In a period where we're barely flirting with 1.5C of warming yet seeing breathaking and disturbingly unusual weather phenomena, biological impacts and disastrous effects on human affairs, this obviously comes as bad news. It's accompanied by the usual litany of other wages of complacency, including record-high increases in atmospheric CO2 concentration.  The week also sees a nasty inventory of indicators of how political processes underpinning production of public policy to check and repair this unfolding disaster are at risk from alliances of narrow self-interests. 

"It's all a little much," to say the least. We can and do productively channel the energy of anger to produce positive results, but despair is hard or impossible to catalyze into useful action. With this week's bundle of results a feeling of hopelessness may be knocking on our psychological doors. How do we refuse this invitation?

How about heeding expert advice from climate scientists?

While it's true that hope is not a plan and optimisim needs to be backed by methods, it's equally true that our species has often survived on nothing more than wishes. People who know climate science and climate change at the deepest levels suggest we dig into our reserves. We must carry on with imagining and pursuing a better future. As an antidote to despair we recommend reading this article by former UN climate convention head Christiana Figueres, who has shown what's possible by her shepherding us to the seeming impossibility of the 2015 Paris Climate Convention. We can also listen to practical advice from a younger perspective offered by British Antarctic Survey scientist Dr. Ella Gilbert, whose thrust essentially boils down to "get informed, and take that information to your political processes." 

As Gilbert says, we are doomed to damage— but every avoidance measure we take adds up. We're on a bus headed for a brick wall, but we do have the power to push harder on the brakes and thereby save rows of passengers. Our understanding of climate and our available suite of technologies are more than adequate to deal with our situation; it's "only" lack of coherent and concerted public policy that is making our harm larger. With powerful forces aligned against improved public policy, even if we're feeling very blue indeed we can and must continue to participate in creating our future. It's helpful to note: this is not wishful thinking but instead proven method, a means of action known to work. Example? While it's by no means a perfect outcome, the Paris Convention is undoubtedly going to produce a marginally better future. 

In terms of results, giving up looks exactly like complacency. Are we complacent? No. Let's not behave as though we are. Being complete citizens of our planet by diving into politics armed with information is our way forward. As messy and sometimes repugnant as political processes are, they're the factory where public policy is made— and only effective public policy is going to save us from ourselves. 

Stories we promoted this week, by publication date:

Before May 5



Skeptical Science New Research for Week #19 2024

Posted on 9 May 2024 by Doug Bostrom, Marc Kodack

Open access notables

A Global Increase in Nearshore Tropical Cyclone Intensification, Balaguru et al., Earth's Future:

Tropical Cyclones (TCs) inflict substantial coastal damages, making it pertinent to understand changing storm characteristics in the important nearshore region. Past work examined several aspects of TCs relevant for impacts in coastal regions. However, few studies explored nearshore storm intensification and its response to climate change at the global scale. Here, we address this using a suite of observations and numerical model simulations. Over the historical period 1979–2020, observations reveal a global mean TC intensification rate increase of about 3 kt per 24-hr in regions close to the coast. Analysis of the observed large-scale environment shows that stronger decreases in vertical wind shear and larger increases in relative humidity relative to the open oceans are responsible. Further, high-resolution climate model simulations suggest that nearshore TC intensification will continue to rise under global warming. Idealized numerical experiments with an intermediate complexity model reveal that decreasing shear near coastlines, driven by amplified warming in the upper troposphere and changes in heating patterns, is the major pathway for these projected increases in nearshore TC intensification.

Investigating the potential for students to contribute to climate data rescue: Introducing the Climate Data Rescue Africa project (CliDaR-Africa), Noone et al., Geoscience Data Journal:

The majority of available climate data in global digital archives consist of data only from the 1940s or 1950s onwards, and many of these series have gaps and/or are available for only a subset of the variables which were actually observed. However, there exist billions of historical weather observations from the 1700s, 1800s, and early 1900s that are still in hard-copy form and are at risk of being lost forever due to deterioration. An assessment of changes in climate extremes in several IPCC regions was not possible in IPCC AR6 WGI owing, in many cases, to the lack of available data. One such region is Africa, where the climate impact research and the ability to predict climate change impacts are hindered by the paucity of access to consistent good-quality historical observational data. The aim of this innovative project was to use classroom-based participatory learning to help transcribe some of the many meteorological observations from Africa that are thus far unavailable to researchers. This project transcribed quickly and effectively station series by enrolling the help of second-year undergraduate students at Maynooth University in Ireland.

A medical language for climate discourse, Forgács, Frontiers in Climate (perspective):

However scientifically accurate the messages climate scientists have put forward, the appropriate inferences may not have been drawn by most of their audiences. One of the main reasons may be that scientific metaphors allow for multiple interpretations, yet, because of their expressive power, they impact discourses disproportionately. Climate communication took a path of euphemistic scientific expressions partially due to the noble scientific norms of self-restraint and modesty, but the hidden implications of climate jargon distort the way non-experts think about the heating climate. Consequently, the current climate jargon hinders informed decisions about Earth’s life support systems. Changing the softened expressions of climate language, from the cool of basic research to the heat and compassion of medical contexts, may allow for more productive public and political debates – which may lead to more powerful policy solutions. 

The carbon dioxide removal gap, Lamb et al., Nature Climate Change:

In our study we found that compared with 2020, the most ambitious national proposals for CDR imply an additional 0.5 GtCO2 yr–1 of removals by 2030, and 1.9 GtCO2 yr–1 by 2050. Compared with CDR scaling in Paris Agreement-consistent scenarios, we found that these national CDR proposals tend to fall short by hundreds of megatonnes of carbon dioxide in 2030 to several gigatonnes of carbon dioxide in 2050, highlighting a ‘CDR gap’. However, we find that the most ambitious proposals do come close to levels in a low-energy-demand scenario where CDR requirements are minimized, suggesting that if countries pledge more ambitious emissions reductions consistent with these scenarios, the CDR gap will be closed.

Burying problems? Imaginaries of carbon capture and storage in Scandinavia, Lefstad et al., Energy Research & Social Science:

We reviewed the scientific literature on CCS in Scandinavia to identify and analyse prevalent imaginaries for the role of this technology in the region. Imaginaries capture ideas about the future use of technologies. They are deeply political in that they help define what futures are seen as possible and desirable. Studying CCS imaginaries can grant insights into how current structures and interests shape future climate mitigation pathways. Our results show that one dominant imaginary defines the scientific debate, which envisions using CCS to preserve the industrial base of the region while seeking to meet climate goals. This dominant imaginary builds its appeal and legitimacy around three main characteristics: 1) scientific authority, which justifies the need for large-scale CCS, 2) greening the industrial regime, which gives it a specific purpose, and 3) Scandinavian exceptionalism, which mobilises existing infrastructure and regional know-how combined with a narrative of national environmental leadership. 

From this week's government/NGO section

Denial, Disinformation, and Doublespeak: Big Oil's Evolving Efforts to Avoid Accountability or Climate ChangeDemocratic staff of the House Committee on Oversight and Accountability and Democratic staff of the Senate Budget Committee, United States Congress:

The joint staff investigation, focused on ExxonMobil Corporation (Exxon), Chevron Corporation (Chevron), Shell USA Inc. (Shell), BP America Inc. (BP), the American Petroleum Institute (AI), and the Chamber of Commerce (the Chamber), provides a rare glimpse into the extensive efforts undertaken by fossil fuel companies to deceive the public and investors about their knowledge of the effects of their products on climate change and to undermine efforts to curb greenhouse gas emissions. Documents demonstrate for the first time that fossil fuel companies internally do not dispute that they have understood since at least the 1960s that burning fossil fuels causes climate change and then worked for decades to undermine public understanding of this fact and to deny the underlying science. Big Oil’s deception campaign evolved from explicit denial of the basic science underlying climate change to deception, disinformation, and doublespeak. The fossil fuel industry relies on trade associations to spread confusing and misleading narratives and to lobby against climate action. All six entities—Exxon, Chevron, Shell, BP, API, and the Chamber—obstructed and delayed the Committees’ investigation.

For Our Future: Indigenous Resilience ReportReed et al., Government of Canada:

In recent years, Canada has increasingly faced severe impacts of climate change, including higher temperatures, shifting rainfall patterns, extreme weather events, and rising sea levels. Climate change has already impacted First Nations, Inuit, and Métis livelihoods, culture, social relations, food security, health, well-being, and ways of life. Despite experiencing disproportionate impacts to climate change, Indigenous Peoples have been actively responding to environmental change since time immemorial and have developed Indigenous Knowledge Systems to respond to it. For Canada to reduce some of the worst impacts of the climate crisis it currently faces, Indigenous Knowledge Systems need to be considered. This is the first Indigenous-led report that draws on Indigenous knowledge, perspectives, and experiences to explore multidimensional and intersecting aspects of climate change impacts and adaptation.

139 articles in 59 journals by 1099 contributing authors

Physical science of climate change, effects

A Lagrangian perspective on the lifecycle and cloud radiative effect of deep convective clouds over Africa, Jones et al., Atmospheric Chemistry and Physics Open Access 10.5194/acp-24-5165-2024

Drivers and mechanisms of heatwaves in South West India, Dalal et al., Climate Dynamics 10.1007/s00382-024-07242-x

The Role of Diabatic Heating in the Midlatitude Atmospheric Circulation Response to Climate Change, Ghosh et al., Journal of Climate 10.1175/jcli-d-23-0345.1



Climate Adam: How to visualise Climate Change (ft. Katharine Hayhoe)

Posted on 8 May 2024 by Guest Author

This video includes conclusions of the creator climate scientist Dr. Adam Levy. It is presented to our readers as an informed perspective. Please see video description for references (if any).

Climate change is everywhere. And when something's everywhere it can feel like it's nowhere. So how do we get our heads around something so huge and abstract - whether it's thinking about extreme weather, or the fossil fuels producing CO2 and driving the problem? I'm joined by one of my all time climate heroes - Katharine Hayhoe - to share some of our favourite ways of thinking about the climate crisis

Support ClimateAdam on patreon:

Also check out @globalweirding for more of Katharine Hayhoe's incredible communication!



At a glance - Tree ring proxies and the divergence problem

Posted on 7 May 2024 by John Mason, BaerbelW

On February 14, 2023 we announced our Rebuttal Update Project. This included an ask for feedback about the added "At a glance" section in the updated basic rebuttal versions. This weekly blog post series highlights this new section of one of the updated basic rebuttal versions and serves as a "bump" for our ask. This week features "Tree-ring proxies and the divergence problem". More will follow in the upcoming weeks. Please follow the Further Reading link at the bottom to read the full rebuttal and to join the discussion in the comment thread there.


At a glance

"Trees tell of past climates: but are they speaking less clearly today?" That was the intriguing title of a paper published in the peer-reviewed journal, Philosophical Transactions of the Royal Society of London, in 1998. The authors discussed various aspects of the use of tree-rings as representatives - or proxies - of past climatic patterns.

Tree growth is sensitive to temperature. Because of that, warmer wetter periods produce wider tree-ring patterns. When it's colder and dryer, the rings are narrower, indicating slow growth. In this way, the width and density of tree-rings in ancient trees serve as a proxy for temperature. That makes it possible to reconstruct temperature records going back over many centuries. For example, historic events such as major volcanic explosions tend to lead to global cooling. Such events show up very well in tree-ring reconstructions.

In more recent times, since the late 19th century, we also have the observational temperature record to compare with tree-ring reconstructions. Agreement between the two datasets is at first close. However, in middle and especially high latitude sites, the correlation breaks down after 1960. At this point, while temperatures rise, tree-ring width shows a falling trend - a decline. This divergence between temperature and tree growth is called, imaginatively enough, the divergence problem.

The decline, or divergence problem had been recognised, regularly discussed and written about since around 1995. That's 14 years before anyone had ever heard of 'climategate' and the song and dance that the science–deniers made of 'hide the decline'. If anything should serve as a quality-control alert for the output of science-deniers, it's right there.

Now, everything that happens has a cause, but not all causes are straightforward. There are plenty of ways to put stress on plants and stress makes growth-patterns abnormal. The trouble is that such stress-factors often vary in an irregular fashion and independently of one another. Even in a 2023 paper, the detailed cause of the divergence problem was described as being accompanied by 'significant controversies'. It's real, but it's complicated, in other words.

Temperature-induced drought stress and changes in seasonality are likely to be relevant here. Also likely to have had a role is the phenomenon of ‘Arctic dimming'. The term 'dimming' refers to reduced sunshine reaching the surface in some circumpolar regions, due to industrial aerosol pollution. Northern Hemisphere pollution tends to accumulate over the Arctic. Reduced sunshine affects photosynthesis and in return that impacts upon plant health and growth. Indeed, a 2021 paper ominously commented that the effects of Arctic aerosols on net primary production - growth - were particularly important in light of the current race to exploit natural resources north of the Arctic circle.

The extensive boreal forests of the north play a major role in shaping Earth’s carbon cycle and climate system. In the divergence problem, they have raised a red flag. Something up there is wrong and it should come as no surprise that, once again, our reckless misuse of our planet is high on the list of suspects for that.

Please use this form to provide feedback about this new "At a glance" section. Read a more technical version below or dig deeper via the tabs above!

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Why India is key to heading off climate catastrophe

Posted on 6 May 2024 by dana1981

This is a re-post from Yale Climate Connections

a man washing a solar array

A farmworker cleans the solar panels of a solar water pump in the village of Jagadhri, Haryana Country, India. (Photo credit: Prashanth Vishwanathan/ IWMI)

Decisions made in India over the next few years will play a key role in global efforts to head off the most catastrophic effects of climate change.

The country has one of the world’s fastest-growing economies, and its energy consumption is growing rapidly as a result — but it still relies largely on fossil fuels. India has a general election that will wrap up in June 2024, and both major parties say they support moving the country away from fossil fuels as quickly as possible, a position backed by a sizable majority of citizens.

Global institutions like the International Monetary Fund and World Bank have pledged to help finance efforts to cut climate pollution. But many experts say more help is needed if India and other developing countries are to meet their energy goals.

As Indian Environment Secretary Rameshwar Prasad Gupta said in an interview with the Economic Times, “Without adequate climate finance being definitively available, we can’t commit” to curbing India’s carbon emissions fast enough to meet the country’s targets under the global Paris climate agreement of 2015.

How much does India contribute to climate change?

India has only generated about 3% of total historical climate pollution compared to 25% for the United States. But it is the third-highest carbon-polluting country today. To have a chance of meeting the Paris targets, the world cannot afford for India and other developing countries to follow the same path that made rich countries wealthy: burning “cheap” fossil fuels, because we now know the tremendous indirect costs of fossil fuel via environmental and health damages.

The size of India’s economy has almost doubled since Narendra Modi became prime minister a decade ago. The country surpassed China last year to become the most-populated country in the world with over 1.4 billion people. The number of Indians living in poverty has declined from 317 million in 2016 to 140 million today, although 90% of the population still lives on less than $10 per day.

With improved living conditions comes greater energy use and more pollution. India’s coal consumption has nearly tripled since 2005. India accounts for 14% of global coal demand, behind only China and is expected to account for most of the increase in global coal consumption in the coming years. India’s overall climate pollution is about 75% higher than in 2005, largely due to coal-fired power.

Still, although per-person carbon emissions in India have doubled since 2005, the average Indian’s carbon footprint remains less than half the world average and seven times lower than the average American’s.

Sources of electricity generation in India. Created by Dana Nuccitelli with data from the government of India.



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