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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.


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!

Click for Further details



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!

Click for Further details



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.



2024 SkS Weekly Climate Change & Global Warming News Roundup #18

Posted on 5 May 2024 by BaerbelW, Doug Bostrom, John Hartz

A listing of 26 news and opinion articles we found interesting and shared on social media during the past week: Sun, April 28, 2024 thru Sat, May 4, 2024.

Story of the week

"It’s straight out of Big Tobacco’s playbook. In fact, research by John Cook and his colleagues has shown that character assassination has been one of the most common ways in which fossil fuel interests have attempted to deny accountability for the climate crisis."

— Geoffrey Supan

Why go low? Because when one can't fly, one creeps and crawls. Widely remarked: to fall back on ad hominem remarks is to declare intellectual surrender, at best a Hail Mary attempt to change topics— and easily spotted even by children arguing on a playground. "Going ad hom" is a common failure mode when talk turns to human-caused climate change. US Senator (from hydrocarbon-rich Louisiana) John Kennedy's  waving the white flag and ceding a vast territory of evidence and facts to Geoffrey Supan by diving into the gutter is the subject of our story of the week. Kennedy humiliated himself in the most public of places: in a televised US Senate Budget Committee hearing.

In a nutshell, Senator Kennedy attempted to discredit Prof. Supan and divert attention from the content of Supan's testimony by highlighting a single social media item Supan had reposted, an innocuous description of tactical choices made by a youth-led climate action organization.This was thin fabric, comically so, and made worse by Kennedy's needing to read various expletives from other posts— unrelated to Supan's repost— into the congressional record. 

Senator Kennedy's weird diversion encourages us to speculate— and legitimates scrutiny of Kennedy himself. With Kennedy's having created his own first mover disadvantage by changing the topic of the hearing from science to personalities, we are free in turn to wonder over his puzzling public messaging. Are we are seeing genuine inability to track a topic, or instead something more resembling a retail transaction? Emily Atkin's coverage in Heated tells the whole story and offers hints of where a parsimonious interpretation may lie.

Given Prof. Supan's testimony about the connection between fossil fuel industry contributions and politician support for industry agendas, a reasonable person reading this story must form their own conclusions over the root cause of Kennedy's rhetorical flop. One would think Senator Kennedy would understand how he was walking into a self-made trap of creating suspicions and doubts, issuing an unfavorable invitation to comparisons. After all, Kennedy was among the top four congressional recipients of fossil fuel industry campaign contributions for the 2022 election cycle. With money generally not being handed out in large quantities for zero consideration, one might see this as explanation for an otherwise curious choice to look foolish in front of the world. 

As we can't read Senator Kennedy's mind, we are stuck with speculation. Is he only feigning incompetence? We can't truly know. It is of course for Senator Kennedy to choose how he leads our imaginations and is perceived— we can only respect his wishes, for bad or worse. If Kennedy wants to be remembered by history as "fond of loudly losing, but why?" who are we to question that?

Stories we promoted this week, by publication date:

Before April 28

April 28



Skeptical Science New Research for Week #18 2024

Posted on 2 May 2024 by Doug Bostrom, Marc Kodack

Open access notables

Generative AI tools can enhance climate literacy but must be checked for biases and inaccuracies, Atkins et al., Communications Earth & Environment:

In the face of climate change, climate literacy is becoming increasingly important. With wide access to generative AI tools, such as OpenAI’s ChatGPT, we explore the potential of AI platforms for ordinary citizens asking climate literacy questions. Here, we focus on a global scale and collect responses from ChatGPT (GPT-3.5 and GPT-4) on climate change-related hazard prompts over multiple iterations by utilizing the OpenAI’s API and comparing the results with credible hazard risk indices. We find a general sense of agreement in comparisons and consistency in ChatGPT over the iterations. GPT-4 displayed fewer errors than GPT-3.5. Generative AI tools may be used in climate literacy, a timely topic of importance, but must be scrutinized for potential biases and inaccuracies moving forward and considered in a social context. Future work should identify and disseminate best practices for optimal use across various generative AI tools.

Astronomy’s climate emissions: Global travel to scientific meetings in 2019, Gokus et al., PNAS Nexus:

Travel to academic conferences—where international flights are the norm—is responsible for a sizeable fraction of the greenhouse gas (GHG) emissions associated with academic work. In order to provide a benchmark for comparison with other fields, as well as for future reduction strategies and assessments, we estimate the CO2-equivalent emissions for conference travel in the field of astronomy for the prepandemic year 2019. The GHG emission of the international astronomical community’s 362 conferences and schools in 2019 amounted to 42,500 tCO2e, assuming a radiative-forcing index factor of 1.95 for air travel. This equates to an average of 1.0 ± 0.6 tCO2e per participant per meeting. The total travel distance adds up to roughly 1.5 Astronomical Units, that is, 1.5 times the distance between the Earth and the Sun. We present scenarios for the reduction of this value, for instance with virtual conferencing or hub models, while still prioritizing the benefits conferences bring to the scientific community.

The IPCC’s reductive Common Era temperature history, Esper et al., Communications Earth & Environment:

Common Era temperature variability has been a prominent component in Intergovernmental Panel on Climate Change reports over the last several decades and was twice featured in their Summary for Policymakers. A single reconstruction of mean Northern Hemisphere temperature variability was first highlighted in the 2001 Summary for Policymakers, despite other estimates that existed at the time. Subsequent reports assessed many large-scale temperature reconstructions, but the entirety of Common Era temperature history in the most recent Sixth Assessment Report of the Intergovernmental Panel on Climate Change was restricted to a single estimate of mean annual global temperatures. We argue that this focus on a single reconstruction is an insufficient summary of our understanding of temperature variability over the Common Era. We provide a complementary perspective by offering an alternative assessment of the state of our understanding in high-resolution paleoclimatology for the Common Era and call for future reports to present a more accurate and comprehensive assessment of our knowledge about this important period of human and climate history.

Phasing out coal power in two major Southeast Asian thermal coal economies: Indonesia and Vietnam, Do & Burke, Energy for Sustainable Development:

The phase-out of unabated coal power is crucial for meeting climate agreements in coal-dependent economies such as Indonesia and Vietnam. Despite both countries committing to the 2021 Global Coal to Clean Power Transition Statement, translating phase-out pledges into action poses considerable challenges. Drawing insights from interviews with government, civil society, and industry experts, this study identifies the key barriers hindering coal phase-out in each country. Concerns about potentially escalating electricity prices and power shortages loom large, with the former being more prominent in Indonesia and the latter more prominent in Vietnam. The obstacles appear particularly significant in Indonesia for reasons including its higher coal dependence. We conclude that prioritizing renewable energy growth, as well as halting the construction of new coal plants, would be the most practical and viable way forward for both countries rather than an oversized early focus on coal plant closures. The analysis is of high relevance to informing plans under the two countries' Just Energy Transition Partnerships.

The decision maker’s lament: If I only had some science!, Bisbal, Ambio (perspective):

Environmental decision makers lament instances in which the lack of actionable science limits confident decision-making. Their reaction when the needed scientific information is of poor quality, uninformative, unintelligible, or altogether absent is often to criticize scientists, their work, or science in general. The considerations offered here encourage decision makers to explore alternative approaches to alleviate their disappointment. Ironically, many researchers lament the lack of support for the science they wish to deliver and accuse decision makers of failing to realize the value of the scientific studies they propose. Both communities would benefit by remembering that producing actionable science for a pending decision requires knowing the context for that decision beforehand. They may also look inward. Only then will they find answers to the question: What can I do within my own capacity to ensure that the necessary actionable science becomes available and facilitate its use to inform decisions?

From this week's government/NGO section

Heavy precipitation hitting vulnerable communities in the UAE and Oman becoming an increasing threat as the climate warmsZachariah et al., World Weather Attribution:

From April 14 to 15 2024, the United Arab Emirates (UAE) and the northern parts of Oman were hit by exceptionally heavy rainfall causing massive disruption in infrastructure and public life in the area and leading to at least 20 fatalities in Oman and four in the United Arab Emirates UAE. The disagreement between model results and observations prevents the authors from concluding with certainty that human-induced climate change is the main driver making this event more likely. However, while multiple reasons could explain the absence of a trend in the model results, the authors have no alternative explanation for a trend in observations other than the expectation of heavy rainfall increasing in a warmer climate.

Climate Reality on-Screen: The Climate Crisis in Popular Films, 2013-22Schneider-Mayerson, et al., Buck Lab for Climate and Environment, Colby College:

The authors provide audience members, screenwriters, filmmakers, studios, and researchers with a straightforward way to evaluate whether climate change is represented—or omitted—in any narrative through a two-part, binary evaluation tool that is simple, illuminating, and powerful.

140 articles in 64 journals by 910 contributing authors

Physical science of climate change, effects

Asymmetric impacts of forest gain and loss on tropical land surface temperature, Zhang et al., Nature Geoscience 10.1038/s41561-024-01423-3

Carbon budget concept and its deviation through the pulse response lens, Avakumovi?, Earth System Dynamics Open Access 10.5194/esd-15-387-2024

Observations of climate change, effects

Anthropogenic influence on seasonal extreme temperatures in eastern China at century scale, Hu et al., Weather and Climate Extremes Open Access 10.1016/j.wace.2024.100675



At a glance - Clearing up misconceptions regarding 'hide the decline'

Posted on 30 April 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 "Clearing up misconceptions regarding 'hide the decline'". 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

It's been many years since 'climategate' - when in 2009, the email server at the Climate Research Unit, University of East Anglia, was hacked. The unidentified hacker helped themselves to thousands of emails. These were sifted through and a selection was in due course made available for public download on a Russian server.

What followed was typical of the tactics used in the campaign to deny the existence of human-caused climate change and is illustrative for that reason. A lot of this manufactured controversy centred on one email, written by Dr Phil Jones, in which the following sentence was picked out and trumpeted all over the media:

"I've just completed Mike's Nature trick of adding in the real temps to each series for the last 20 years (ie from 1981 onwards) and from 1961 for Keith's to hide the decline."

"Gotcha!", the deniers proclaimed.

Climategate was marketed to the public by encouraging them to take such sentences at face value - without any idea of what they actually meant. The notion being planted was that climate scientists were busy covering up declining temperatures.

It meant nothing of the sort. The people in that email were not talking about temperatures. They were talking about tree-rings.

"Mike's Nature trick" referred to a technique described in a 1998 Nature paper. The paper presented a 600 year-long global temperature reconstruction by Michael Mann and colleagues. Michael has long used tree-ring growth patterns in ancient wood to reconstruct conditions at the time those rings formed. The basic idea is that in cold, dry years, trees grow more slowly so their rings are relatively narrow and densely-spaced. In warm wet years, it's the opposite.

The "trick" is the technique of plotting recent instrumental data - in other words direct temperature measurements - alongside the reconstructed tree-ring data for the time they overlap. Why? Because it's one way of checking if the reconstructed tree-ring data are a good proxy for temperatures of the past. It therefore makes entire sense to run such checks. Now to the 'decline'. What declined?

Beyond a certain point on the timeline, around 1960, the temperature reconstructions based on some tree-ring data fell away and downwards from observed thermometer records. They declined from reality. This only happened with certain tree-ring datasets from specific places. Known as the 'divergence problem', it had been discussed in the scientific literature since the mid 1990s - 15 years before 'climategate'. However, not a lot of people realised that. How lucky for the deniers. "Hide the decline!", they chanted feverishly, to anybody who would listen.

Everything that occurs in the physical world has a cause. The divergence of temperature reconstructions, based on tree-ring growth, from the observational temperature record is a case in point. The loss of tree-ring sensitivity to temperatures kicked in around 1960. It only affected certain tree-species at certain locations. However, in those cases the post-1960 tree-ring datasets do not reflect the actual conditions. In other words, the data are useless. That's the decline for you. Much ado about nothing.

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



Pinning down climate change's role in extreme weather

Posted on 29 April 2024 by Guest Author

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

In the wake of any unusual weather event, someone inevitably asks, “Did climate change cause this?” In the most literal sense, that answer is almost always no. Climate change is never the sole cause of hurricanes, heat waves, droughts, or any other disaster, because weather variability always plays a primary role in the genesis of the events.

However, climate change can make these events more intense and, given the non-linearities in the damages, this can vastly increase the damage and misery from extreme weather. So quantifying the role of climate change is therefore of great interest.

To do this, scientists turn to extreme event attribution studies. These rely on three separate lines of evidence. The first is the observational record: If you have good observations of the climate over a long enough period, the data set can be statistically analyzed to determine whether the event in question is becoming more frequent as the climate warms.



2024 SkS Weekly Climate Change & Global Warming News Roundup #17

Posted on 28 April 2024 by BaerbelW, Doug Bostrom, John Hartz

A listing of 31 news and opinion articles we found interesting and shared on social media during the past week: Sun, April 21, 2024 thru Sat, April 27, 2024.

Story of the weekScreen capture of CarbonBrief news item.

Anthropogenic climate change may be the ultimate shaggy dog story— but with a twist, because here endless subplots definitely depend upon one central element in the unfolding drama of our grand physics accident: the dominant story mechanic is that we're changing Earth's climate. This leads to outcomes. One way of seeing this is via the abstraction of statistics, while another perspective is that of individual experiences each of which is only an anecdote but together lead us back to statistics. Our story of the week is Carbon Brief's annual summary State of the climate: 2024 off to a record-warm start:

This year is shaping up to either match or surpass 2023 as the hottest year on record.

Global temperatures have been exceptionally high over the past three months – at around 1.6C above pre-industrial levels – following the peak of current El Niño event at the start of 2024.

The past 10 months have all set new all-time monthly temperature records, though the margin by which new records have been set has fallen from around 0.3C last year to 0.1C over the first three months of 2024. 

April 2024 is on track to extend this streak to 11 record months in a row.

Author Zeke Hausfather continues this informative summary by delivering a complete numerical rundown of where we stand with regard to global surface temperature. In sum we're we're living a spike. Our shock is belated. Expert opinion suggests we're  experiencing another wiggle in a upward-trending graph. We've seen this before in historical records, only less remarked given we're only now having our first brush with 1.5 °C of overall warming.  In any case, the directed herky jerky plot of global warming inevitably unfolds a bevy of subplots exemplified by other stories from this week's roundup, "anecdotes" in the grand scheme of global temperature records:

This shaggy dog story will continue to proliferate and evolve while we wait to reach our next record year. 

Stories we promoted this week, by publication date:

Before April 21

April 21



Fact Brief - Is Antarctica gaining land ice?

Posted on 27 April 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.

Is Antarctica gaining land ice?

noWhile Antarctic sea ice varies seasonally, the continent's land ice has continued to melt at an increasing pace.

Sea ice forms during the Antarctic winter and retreats during the warmer months. Such freeze-thaw cycles have no impact on sea levels since they happen within the ocean. However, Antarctic land ice has seen a net decrease, resulting in a significant increase in fresh water flowing into the sea. That does affect global sea levels.

The behavior of Antarctic land ice varies from region to region. In particular, the West Antarctic Peninsula has seen drastic ice retreat. On the other hand, East Antarctica's land ice has remained relatively stable to date. But if global warming crosses a specific threshold, serious loss is expected to occur. The planet has already moved a third of the way towards that threshold and will pass it within a century, if fossil fuel burning continues unabated.

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.




Simon Clark: The climate lies you'll hear this year

Posted on 26 April 2024 by BaerbelW, John Cook, John Mason

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

This year you will be lied to! Simon Clark helps prebunk some misleading statements you'll hear about climate. The video includes a few interview snippets with John Cook and John Mason while a longer version of the interview is available on subscription based Nebula.

Support Simon Clark on patreon:



Skeptical Science New Research for Week #17 2024

Posted on 25 April 2024 by Doug Bostrom, Marc Kodack

Open access notables

Ice acceleration and rotation in the Greenland Ice Sheet interior in recent decades, Løkkegaard et al., Communications Earth & Environment:

In the past two decades, mass loss from the Greenland ice sheet has accelerated, partly due to the speedup of glaciers. However, uncertainty in speed derived from satellite products hampers the detection of inland changes. In-situ measurements using stake surveys or GPS have lower uncertainties. To detect inland changes, we repeated in-situ measurements of ice-sheet surface velocities at 11 historical locations first measured in 1959, located upstream of Jakobshavn Isbræ, west Greenland. Here, we show ice velocities have increased by 5–15% across all deep inland sites. Several sites show a northward deflection of 3–4.5° in their flow azimuth. The recent appearance of a network of large transverse surface crevasses, bisecting historical overland traverse routes, may indicate a fundamental shift in local ice dynamics. We suggest that creep instability—a coincident warming and softening of near-bed ice layers—may explain recent acceleration and rotation, in the absence of an appreciable change in local driving stress.

Record-breaking fire weather in North America in 2021 was initiated by the Pacific northwest heat dome, Jain et al., Communications Earth & Environment:

The 2021 North American wildfire season was marked by record breaking fire-conducive weather and widespread synchronous burning, extreme fire behaviour, smoke and evacuations. Relative to 1979–2021, the greatest number of temperature and vapor pressure deficit records were broken in 2021, and in July alone, 3.2 million hectares burned in Canada and the United States. These events were catalyzed by an intense heat dome that formed in late June over western North America that synchronized fire danger, challenging fire suppression efforts. Based on analysis of persistent positive anomalies of geopotential heights, the heat dome accounted for 21–34% of the total area burned in 2021. The event was 59% longer, 34% larger and had 6% higher maximum amplitude than the same event would have been without a warming climate. Climate change will continue to magnify heat dome events, increase fire danger, and enable extreme synchronous wildfire in forested areas of North America.

Future Slower Reduction of Anthropogenic Aerosols Enhances Extratropical Ocean Surface Warming Trends, Gu et al., Geophysical Research Letters:

Global surface temperature short-term trends fluctuate between cooling and fast-warming under the combined action of external forcing and internal variability, significantly influencing the detectability of near-term climate change. A key driver of these variations is anthropogenic aerosols (AAs), which have undergone a non-monotonic evolution with rapid reduction in recent decades. However, their reduction is projected to decelerate under a high carbon emission scenario, yet the impact on surface temperature trends remains unknown. Here, using initial-perturbation large ensembles, we find that future slowdown in AA reduction over Europe and North America expedites the subpolar North Atlantic surface warming by intensifying the Atlantic meridional overturning circulation. Further, it accelerates the South Indian Ocean and Southern Ocean surface warming through positive low-cloud feedback and oceanic dynamical adjustment, triggered by the poleward migration of westerlies under interhemispheric energy constraint. These AA-driven warmings exacerbate greenhouse warming, significantly enhancing the detectability of local decadal warming trends.

Deglacial Pulse of Neutralized Carbon From the Pacific Seafloor: A Natural Analog for Ocean Alkalinity Enhancement?, Green et al., Geophysical Research Letters:

The ocean carbon reservoir controls atmospheric carbon dioxide (CO2) on millennial timescales. Radiocarbon (14C) anomalies in eastern North Pacific sediments suggest a significant release of geologic 14C-free carbon at the end of the last ice age but without evidence of ocean acidification. Using inverse carbon cycle modeling optimized with reconstructed atmospheric CO2 and 14C/C, we develop first-order constraints on geologic carbon and alkalinity release over the last 17.5 thousand years. We construct scenarios allowing the release of 850–2,400 Pg C, with a maximum release rate of 1.3 Pg C yr−1, all of which require an approximate equimolar alkalinity release. These neutralized carbon addition scenarios have minimal impacts on the simulated marine carbon cycle and atmospheric CO2, thereby demonstrating safe and effective ocean carbon storage. This deglacial phenomenon could serve as a natural analog to the successful implementation of gigaton-scale ocean alkalinity enhancement, a promising marine carbon dioxide removal method.

From this week's government/NGO section: 

Climate Impact of Primary Plastic ProductionKarali et al., Lawrence Berkeley National Laboratory:

Plastics show the strongest production growth of all bulk materials over the last decade. The industry’s current growth trajectory is exponential and plastic production is expected to double or triple by 2050. The rapidly increasing production of plastics and the continued reliance on fossil fuels for production, have contributed to numerous environmental problems and health harms. As a result, plastic pollution has become an increasing threat to natural ecosystems, human health and climate. However, there is a lack of granularity on the contribution of the primary plastics specifically to greenhouse gas (GHG) emissions and their impact on the remaining global carbon budget needed to stay below a 1.5°C or 2°C global average temperature rise. The authors explore the contribution of primary plastic production to climate change disaggregated by polymer and technology.

The Elephant in the Climate Room: Financing Sustainable Security and Supporting Future-Fit SystemsCicarelli et al., The Center for Climate and Security:

The authors outline the key challenges facing policymakers ahead of this year's "Spring Meetings" of the International Monetary Fund and World Bank, particularly in the context of food security challenges, global instability, and gaps in climate finance. The gap in climate finance has implications beyond sustainable development and humanitarian needs. Further, investments in climate adaptation and resilience are essential for addressing the security implications of climate change, helping reduce risks and vulnerabilities, and helping build more stable and secure societies. 

129 articles in 64 journals by 682 contributing authors

Physical science of climate change, effects

Absorption of Solar Radiation by Noctilucent Clouds in a Changing Climate, Lübken et al., Geophysical Research Letters Open Access pdf 10.1029/2023gl107334

Hydrologic cycle weakening in hothouse climates, Liu et al., Science Advances 10.1126/sciadv.ado2515



Water is at the heart of farmers’ struggle to survive in Benin

Posted on 24 April 2024 by Guest Author

This is a re-post from Yale Climate Connections by Megan Valére Sosou

A photo of rows of plants that are climbing up stakes in the ground.Market gardening site of the Itchèléré de Itagui agricultural cooperative in Dassa-Zoumè (Image credit: Megan Valère Sossou)

For the residents of Dassa-Zoumè, a city in the West African country of Benin, choosing between drinking water and having enough food has become a worrying dilemma.

“Last year, our horticultural production plummeted due to water scarcity,” said Chantal Agbangla, a farmer residing in Soclogbo, a town located about 30 minutes by car from the capital of Dassa-Zoumé. “We had to travel nine kilometers to find water, mainly for our agricultural and domestic needs.”

Family farming, a pillar of the economy in Dassa-Zoumè, is more threatened than ever by climate change. Small-scale farms cover only about 2% of cultivable land in the area of Dassa-Zoumé, and their very survival seems threatened because water has become an increasingly precious commodity. Residents can no longer rely on the rainy season, as the irregularity of precipitation has made it an unreliable water source. Instead, they have embraced agroecological horticulture as a contingency plan against climate change. Agroecology emphasizes sustainable farming practices that prioritize water retention in the soil, making this type of farming more resistant to drought.



At a glance - The difference between weather and climate

Posted on 23 April 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 "The difference between weather and climate". 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

How do you go about weather forecasting by yourself? Study the computer models. With experience, you will become familiar with the art - for it takes human interpretation of model output to make the calls. That's what weathermen do.

Forecast model output is freely available online and covers many parameters - pressure, temperature, rainfall and a myriad of others. Different models extend to different end-times - the Global Forecasting System (GFS) extends to T+ 384 hours or 16 days, for example. Pressure, or synoptic charts as they are known, portray the positions and subsequent developments of high and low pressure systems over large swathes of the planet.

Models are run several times a day. If you examine synoptic charts for the same run of several different models, you will see they all look very similar to start with. But if you then follow them through successive time-points - T+24, 48, 72 hours and so on, there will come a point where you start to notice slight and then larger differences between them. This divergence is where confidence in forecasting falls right away.

Forecasting - interpreting the GFS and other model output - is about working with uncertainty in the highly dynamic and to an extent chaotic medium that is our atmosphere. But with experience, you can do your own short term forecasting too, at least for the coming 3-5 days.

Longer-term weather forecasting a week or more in advance is about stating probabilities, not saying what will happen. Very different things. Serious amateur forecasters stick to the shorter, next few days bracket, if they want to avoid egg on their faces. There are a few out there who often make wild claims that usually fail to be borne out by reality. Unfortunately, sections of the more populist media happily quote them. It generates click-baity headlines.

Now, what about climate? Climate differs from weather because it includes certain highly deterministic drivers. Deterministic means they evolve independently of weather but can change the physical conditions on Earth from state A to state B. Cyclic variations in Earth's orbit of the Sun, operating over tens of thousands of years, are a good example. They may only drive average planetary temperature changes of a few degrees Celsius, upwards or downwards. But with the help of climate feedbacks, that is enough to have caused past ice-ages - and to have gotten us out of them again.

Changes in the strength of Earth's greenhouse effect are likewise deterministic, but to a far greater extent. They have forced past transitions from the Hothouse to the Icehouse climate state. Hothouse, by the way, is an ice-free Earth. Because we know how the greenhouse effect works, we can say with confidence that intensifying its strength will cause global temperatures to rise over centuries. What we cannot say is what weather will occur on a certain day at a certain place, decades from now. But there's a handy saying to cover that: "climate trains the boxer, but the weather throws the punches". (Deke Arndt, Climate Monitoring Branch Chief, NCDC, 2010)

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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India makes a big bet on electric buses

Posted on 22 April 2024 by Guest Author

This is a re-post from Yale Climate Connections by Sarah Spengeman

A group of people waiting by the side of a road as a bus pulls upPeople wait to board an electric bus in Pune, India. (Image credit: courtesy of ITDP)

Public transportation riders in Pune, India, love the city’s new electric buses so much they will actually skip an older diesel bus that arrives earlier to wait for a smoother, cooler ride in a new model. This has fed a new problem: overcrowding. Fortunately, more new buses are on the way.

Last fall, India’s Ministry of Housing and Urban Affairs launched a $7 billion initiative to support 10,000 new electric buses in 169 Indian cities. The PM-eBus Sewa program prioritizes small to medium-sized cities of up to 4 million people, particularly those now lacking organized bus service. India hopes this will make public transport — not private vehicles — integral to sustainable urban growth and city culture in the country that last year overtook China to become the world’s most populous nation.

India’s burgeoning cities are expected to be home to an estimated 416 million more people by 2050 — the largest urban increase in the world. Massive growth could worsen both traffic congestion and air quality in a country that already has nine of the 10 most polluted cities on the planet and ranks second in deaths related to transportation pollution.

But more traffic and pollution is not inevitable, since India has yet to build 70 to 80% of city infrastructure that will be needed by 2050. The government initiative aims to make clean, electrified public transportation the norm.

PM-eBus Sewa (Sewa means “service” in Hindi) will also invest in infrastructure like bus depots, interchange facilities, advanced fare collection systems, and fleet charging facilities. New, holistic transport systems in these rapidly developing cities will also create economic opportunities, giving all residents access to affordable, reliable transportation to travel to work or school.

Electric buses require a larger upfront investment even though they are cheaper than diesel buses over their lifetimes due to lower fuel and maintenance costs. Therefore, PM-eBus Sewa will focus on smaller cities with fewer financial resources. It also will use an innovative funding mechanism called a gross cost contract model, which has already succeeded in several Indian cities. The local transportation authority contracts with a private company that owns the bus, often the manufacturer, to operate the bus and handle maintenance, charging, and staffing over a set time period. This allows cities to pay for buses over a longer term rather than all at once.

“India’s cities do want to run bus services but do not have funds for sustained bus operations,” explained Surendra Kumar Bagde, additional secretary, Ministry of Housing and Urban Affairs at the International Council on Clean Transportation’s Clean Transport Summit in New Delhi last August. “PM-ebus Sewa gives this sustained bus operations support.”



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