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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.


Can the economy afford NOT to fight climate change?

Posted on 20 September 2021 by dana1981

This is a re-post from Yale Climate Connections

Those opposing a fast transition to renewable energy and other aggressive action to fight catastrophic climate change often argue that the economic costs would be too great.  Now, with the proliferation of extreme hurricanes, droughts, floods, wildfires, and other disasters linked to a changing climate, it has grown more apparent that the status quo also carries a cost – defined as the “social cost” of carbon.  But recent research indicates existing economic models may have low-balled those potential social costs by trillions of dollars.

Papers accounting for the value of nature and heat-related mortality conclude that the social cost of carbon is in the hundreds of dollars per ton of carbon dioxide pollution.  A new study published in Environmental Research Letters (ERL) also finds that the cost of doing nothing could be 15 times greater yet. The trillion-dollar question for climate economists is: will climate damages have persistent effects that result in slower economic growth?

“Climate change makes detrimental events like the recent heat wave in North America and the floods in Europe much more likely,” noted the new study’s co-author Chris Brierley of the University College London. “If we stop assuming that economies recover from such events within months, the costs of warming look much higher than usually stated. We still need a better understanding of how climate alters economic growth, but even in the presence of small long-term effects, cutting emissions becomes much more urgent.”

That insight has important repercussions for federal climate rules. In adopting new regulations, federal agencies are required to weigh the resulting costs and benefits to American taxpayers. Experts estimate how much a ton of carbon dioxide pollution costs society as a result of the climate change damages it causes. This “social cost” of carbon is notoriously difficult to pin down. Wild cards include uncertainties about the magnitude of climate damages and about the resulting economic costs, and subjective judgments about how much governments value or discount the wellbeing of future generations.



2021 SkS Weekly Climate Change & Global Warming News Roundup #38

Posted on 19 September 2021 by BaerbelW

Listing of articles linked to on the Skeptical Science Facebook Page during the past week: Sun, September 12, 2021 through Sat, September 18, 2021

The following articles sparked above average interest during the week: Do high levels of CO2 in the past contradict the warming effect of CO2?, What would it take for antivaxxers and climate science deniers to ‘wake up’?, Climate scientist in TIME100 most influential list to join Imperial, Fact-checking works to undercut misinformation in many countries, and Scientists scramble to harvest ice cores as glaciers melt.

Articles Linked to on Facebook



Skeptical Science New Research for Week #37, 2021

Posted on 16 September 2021 by doug_bostrom

Go with real guilt, or imaginatively hide?

This week's New Research includes a couple of interesting papers exploring the confused, noisy marketplace of ideas, volitions and impulses we call "the human mind," in connection with thinking about climate change and our responsibility for causing harm and remedy. 

We're all (surely?) familiar with now near-continuous warnings from experts about the trajectory to disaster we're creating in connection with Earth's climate. Whether these warnings are effective is not a closed case and in particular how such warnings might work is an open question needing more investigation. Reactions to warnings in the climate commons leads us through a synopsis of innate or explicit vehicles for delivering cautionary information on climate and possible mechanisms for action elicited by such communications, respectfully noting limitations of prior research on the topic. Lead author Annika Wyss and her team of coathors zero in on the powerful role our emotions seem to play in our comprehension leading to productive responses in our actual behavior, especially feelings of guilt. For those of us familiar with functional guilt as a means of combating procrastination, the authors' conclusions are not necessarily surprising:

Across two studies, we investigated people's affective and behavioral reactions in response to environmental warnings in a threshold public goods game where unsustainable decisions are associated with actual CO2 externalities. We demonstrated that participants show a lasting, yet diminishing decrease in resource extraction after receiving a warning that their group would surpass a critical threshold causing a CO2 emission, should their level of extracting points remain unsustainable. Importantly, our results show that experienced guilt is consistently associated with behavioral change. More specifically, guilt mediates the effect of warnings on pro-environmental behavioral change, meaning that higher levels of guilt are predictive of a stronger reduction of resource extraction after receiving an environmental warning.

At our core and as a species we're of course bent on survival, and survival needs backup mechanisms for when "normal" processes fail. Supposing that we can't feel guilty enough to face the future by behaving better, it appears we have other means of soothing our anxieties.  Avoidance, rationalization, and denial: Defensive self-protection in the face of climate change negatively predicts pro-environmental behavior by Wullenkord & Reese explores our facile competence in avoiding emotional overload by lapsing into irrational reinterpretation and analysis of facts. The authors' findings suggest that guilt goes out the window if  we can (and we do!)  construct a happy story that "it's not going to be that bad"  when presented with a picture so dismal that it might instead arrest us in our tracks. Instead, we hypothesize more comfortable scenarios.

Wullenkord & Reese's findings smack of potential immediate relevance. Faced with a seemingly overwhelmingly challenge, the self-defensive protections they describe may be a circuit breaker tripping in enough heads to affect results in the real world, in a factually negative way that won't be wished out of existence. It's not about denial in the simple sense with which we're familiar; we can see the graveyard and yet whistle past. In enough company as a chorus this is of course detrimental to a better future. Along with the fantasy comes some baggage: we don't feel motivated to do anything concrete to improve outcomes, because of course that motivation will be in conflict with our self-constructed perceptions. "Concrete" not least means clear direction to those giving overall shape to public policy, namely legislators, who in turn direct the efforts of operational civil servants. If we bury our concerns and feelings in elusive wishful thinking, it seems reasonable to conjecture (or, why not leap to a conclusion?) that we won't communicate real world requirements to public servants needing guidance. 



Thinking is Power: How to do your own research

Posted on 15 September 2021 by Guest Author, BaerbelW

TiP-LogoThis is a re-post from the Thinking is Power website maintained by Melanie Trecek-King where she regularly writes about many aspects of critical thinking in an effort to provide accessible and engaging critical thinking information to the general public. Note: This article is the second of a two-part series on “doing your own research.” To read the first article click here.

It seems nearly everyone is “doing their own research” these days. And to some extent it’s understandable: we want to make good decisions and there’s a seemingly endless amount of information available at our fingertips.

Unfortunately, access to information simply isn’t enough. Although it’s difficult to admit, we aren’t as knowledgeable or as unbiased as we’d like to think we are. We often resort to “doing our own research” when we want (or don’t want) something to be true…and so we set out to find “evidence” to make our case. Due to an unfortunate mixture of motivated reasoning and confirmation bias, we end up wildly misled yet even more confident we’re right.

Needless to say, this isn’t how real research works. What you’re actually doing is looking for the results of someone else’s research. The real question is, how do you decide which source to trust?


In a previous article I tried to point out the dangers of doing your own research, which was essentially a plea for intellectual humility and trusting experts. But if you want to “do your own research,” you basically have two options: Find and trust the expert consensus or become an expert yourself and do your own (real) research.



Can we afford (not) to stop Climate Change?

Posted on 14 September 2021 by Guest Author

Again and again we hear that stopping climate change is too expensive. But when we say this, we leave out a crucial part of the story... the cost of climate change itself. So how do we weigh up what stopping global warming is worth?

Support ClimateAdam on patreon:



The hottest summer most Americans have ever lived through

Posted on 13 September 2021 by Guest Author

This is a re-post from Yale Climate Connections by Bob Henson

An 85-year-old record for summer heat set during the Dust Bowl has met its match. In 2021, the contiguous U.S. had its warmest meteorological summer (June-August) on record, according to NOAA’s National Centers for Environmental Information (NCEI). Records going back to 1895 show the 48-state summer average of 74.01°F in 2021 came in just ahead of the summer of 74.00°F recorded in 1936. The margin of 0.01°F is close enough to be considered a statistical tie.

The record is especially noteworthy because many dismissive of climate-change science have trumpeted the heat of the 1930s in their efforts to downplay the importance of recent human-caused climate change in the United States. Doubters have long cited the full-year (not just the summer average) national heat record of 1934 even after it was beaten out in 1988. Since then, six years in the contiguous U.S. have ended up even warmer than either 1934 or 1988.

Figure 1. Average temperatures for the 48 states of the contiguous U.S. for summer (June through August) in records extending from 1895 to 2021. U.S summers have warmed by about 1.5°F over the past 125 years. (Image credit: NOAA/NCEI)



2021 SkS Weekly Climate Change & Global Warming News Roundup #37

Posted on 12 September 2021 by BaerbelW

Listing of articles linked to on the Skeptical Science Facebook Page during the past week: Sun, September 5, 2021 through Sat, September 11, 2021

The following articles sparked above average interest during the week: Climate change deniers are as slippery as those who justified the slave trade, People don’t know what climate experts are talking about, What Smart People Get Wrong About Climate Change Extremes Fact-checking works across the globe to correct misinformation, and Why I am angry.

Articles Linked to on Facebook



Reposted articles from Thinking is Power

Posted on 11 September 2021 by BaerbelW

TiP-LogoIn early August 2021 we started to repost selected articles from the Thinking is Power website maintained by Melanie Trecek-King where she regularly writes about many aspects of critical thinking in an effort to provide accessible and engaging critical thinking information to the general public. This page lists the reposted articles in the sequence we shared them in and is intended as a quick reference.



Implications for mitigating methane emissions in agriculture

Posted on 10 September 2021 by ATTP

This is a re-post from And Then There's Physics

Since I was discussing methane in yesterday’s post, I thought I would highlight a paper on [u]nderstanding the implications for mitigating methane emissions in agriculture (H/T Miles King). The reason I found it interesting, is that it uses GWP* (which I try to explain here), rather than the more standard GWP100, or GWP20, metrics.

The results are nicely explained at the beginning of the paper. When considering agricultural emission scenarios from 2020-2040:

  • A sustained ~0.35% annual decline is sufficient to stop further increases in global temperatures due to agricultural CH4 emissions. This is analogous to the impact of net-zero CO2 emissions.
  • A ~5% annual decline could neutralize the additional warming caused by agricultural CH4 since the 1980s.
  • Faster reductions of CH4 emissions have an analogous impact to removing CO2 from the atmosphere.

What this illustrates is that fairly modest reductions in agricultural methane emissions (~0.35% per year) can largely stop future agricultural methane-driven warming, stronger methane emission reductions (~5% per year) can reverse the agricultural methane-driven warming since about 1980, and even faster reductions would be analagous to negative CO2 emissions.

The reason these results might seem at odds with previous estimates is that GWP* better estimates methane-driven warming than GWP100, or GWP20.

However, even though modest methane emission reductions can have a big impact on future methane-driven warming, the paper also points out that...



Skeptical Science New Research for Week #36, 2021

Posted on 9 September 2021 by doug_bostrom

108 articles by 621 contributing authors

Physical science of climate change, effects

Arctic amplification of climate change: a review of underlying mechanisms
Previdi et al. Environmental Research Letters
Open Access 10.1088/1748-9326/ac1c29

(provisional link) Understanding physical drivers of the 2015/16 marine heatwaves in the Northwest Atlantic

Observations of climate change, effects

Analysis of climatic trends in the upper Blue Nile basin based on homogenized data
Woldesenbet & Elagib Theoretical and Applied Climatology

Spatiotemporal changes and modulations of extreme climatic indices in monsoon-dominated climate region linkage with large-scale atmospheric oscillation
Islam et al. Atmospheric Research

Temporal variations in the frequency of thunderstorm days in Tabriz and its relationship with sunspots frequency and global atmospheric Co2 concentration
Ghavidel et al. Meteorology and Atmospheric Physics

Spatiotemporal Pattern Mining of Drought in the Last 40 Years in China Based on the SPEI and Space–Time Cube
Xu et al. Journal of Applied Meteorology and Climatology

Effects of Barents–Kara Seas ice and North Atlantic tripole patterns on Siberian cold anomalies
Chen et al. Weather and Climate Extremes
Open Access 10.1016/j.wace.2021.100385

Anthropogenic climate change contribution to wildfire-prone weather conditions in the Cerrado and Arc of deforestation
Li et al. Environmental Research Letters
Open Access 10.1088/1748-9326/ac1e3a



The Person Who Lies To You The Most…. Is You

Posted on 8 September 2021 by Guest Author

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

The difference between Cognitive Dissonance, Motivated Reasoning, and Confirmation Bias

Dorothy Martin awoke early one morning in her suburban Chicago home. Her whole arm was tingling. She didn’t know why, but she picked up a pencil next to her bed and started writing. The words that flowed onto the paper were not her own. Even the handwriting was different.


She was receiving a message, a prophecy, from Jesus, currently living on the planet Clarion and going by the name Sananda. Sananda and the other aliens, or Guardians, told Dorothy that she was to spread their messages and teach others how to advance their spiritual development.

The 54 year-old housewife told some friends about her experiences, and the word spread. Soon she and her fellow Seekers were meeting regularly to hear the latest messages from the Guardians. 

On the morning of July 23, 1954, the Guardians sent Dorothy a message. Gather the Seekers. A spaceship would be landing nearby at midday. 

A faithful dozen followed Martin out to an air force base to witness the event, but no flying saucer came. However, they noticed an odd man on the road. He had a strange look in his eyes, refused food and drink, and disappeared as mysteriously as he had appeared. Later, Martin received another message. The man had been Sananda in disguise. Martin was euphoric.

In late August, Sananda again spoke to Martin. This time the message was dire. A huge flood was going to destroy the world.  Doomsday was approaching.  However, the Guardians would come to rescue the chosen ones and take them away in their flying saucer.

The Seekers were told to be prepared for rescue. Many quit their jobs and left their families to move in with Dorothy. And although the flood wasn’t expected until December 21, the followers were told to be ready. The Guardians could come for them at any moment. 

On December 17, there was a phone call from Captain Video from Outer Space, who said a flying saucer would be landing in Dorothy’s backyard at 4:00 pm. One of Dorothy’s previous messages had warned that no metal could be worn on a flying saucer, or it would react with the aliens’ power field. So in frantic preparation, they removed all of their jewelry, tore out their zippers, and pulled the wires out of their bras. (None of them seemed to notice that Captain Video and His Video Rangers was a popular TV series at the time.) 

At 4:00 pm the Seekers were in Dorothy’s backyard awaiting the arrival of the Guardians. Around 5:30 pm they went back inside, shocked and disappointed. Then another message came from Sananda, praising their dedication. It had only been a practice session, to make sure that when the time arrived, things would go smoothly, and they wouldn’t make any mistakes. 

On December 18, Dorothy got another message. The aliens were coming. Immediately. Everyone quickly scrambled outside, once again removing all of their metal. But again, no flying saucer landed to take them away. Some members of the group privately worried that the reason they hadn’t been rescued was because they had metal teeth fillings. 

But they reminded themselves that the real rescue would take place at 12:00 am on December 21, as predicted in the original prophecy.

So the Seekers prepared. They took off all metals. They bundled their “Sacred Books”, transcriptions of Dorothy’s messages, into shopping bags to carry onto the spacecraft. And they waited in tense silence for their ordeal to finally be over.


At five minutes past midnight, the aliens had not yet arrived. Someone in the group reassured everyone. The clock was wrong! Five minutes later, Dorothy announced that there was a slight delay in the plan. At 2:30 am, Dorothy received a message. They should take a coffee break.

At 4:00 am the group sat in silence, faces frozen and expressionless. What had they missed?

But another message came at 4:45 am. Good news!!!! Because of the actions of the Seekers, God had decided to spare the planet from destruction.

Their dedication had saved the world!



Show me the money: a new slogan for the climate movement

Posted on 7 September 2021 by Guest Author, gws

This is a repost from Medium by Karl Burkart of OneEarth

When climate activists make generic statements like, “It’s time for climate action” or “Governments need to act like it’s a climate crisis”, what specifically do they mean? At this stage of the game, with the UN proclaiming a “Code Red for Humanity,” shouldn’t we have better talking points by now?

I’ve been writing for the past few months about the many challenges facing the global climate movement — from attempts to dismiss the 1.5°C goal and confusion around the concept of net zero to hype about misguided tech brosolutions and growing nihilism caused by the steady drip of ruin porn.

It’s not surprising that we don’t have a coherent message to guide the movement and steer the public in a unified call-to-action. Climate change is just so damn complicated, filled with dozens of wonky rabbit holes to fall down — global vs. regional average temperature rise, anthropogenic emissions, carbon budgets, net zero, parts per million, deglaciation, sea level rise, ocean acidification, and on and on — a sea of difficult concepts and terms.

If we are to succeed as a movement, we must find a way to uncomplicate climate change. This is the heavy burden that climate campaigners currently face. We must get our heads above the alphabet soup of UN terminology and deliver a clear and coherent message to the public. But right now, we seem to be failing at that task.

Ask yourself this question: If your aunt or grandparent came over for dinner and wanted you to tell them how we’re going to solve climate change, what would you say? You’ve got less than 60 seconds to capture their attention, so how in the world do you answer this question concisely, coherently, and effectively? (If you have a good zinger response to this question, please drop it in the comments below).

My guess is that the more educated you are, the more likely your answer will involve some really complex topics — UN targets, energy decarbonization, peak emissions, mitigation pathways, adaptation finance, divestment, 100% clean, carbon dioxide removal. Or perhaps you’ll pivot to one of the many battleground issues we’re perpetually fighting — keeping oil in the ground, shutting down coal, stopping gas pipelines, preventing old-growth logging. Either approach, as I’m sure you’ve found, almost assuredly will leave your relative desperate to change the subject.

I’ve been talking to many climate experts, communications gurus, and campaign leaders about how to answer this question. Combined, civil society groups have tried almost every imaginable angle of the 11-dimensional chess game of climate narratives, except for one. For some reason, we’ve shied away from one of the most obvious, and potentially most powerful demands out there…



Why I am “angry”

Posted on 6 September 2021 by gws

A few years ago after I gave a public presentation on climate change science to a lay, but comparatively well-educated audience, I was asked during the Q&A session “aren’t you angry?”. I did not know how to answer. Was I angry? Who would I be angry at?

The organizer of the series of talks I had been part of sent me the audience’ feedback a week later. She said they had never had so many people, so much feedback, and so much praise before. Mind you, there had seemingly not been any climate science deniers in that audience. Otherwise, the result would have been different I suspect.

Why am I writing about this?

When I first got involved in the climate wars about ten years ago it was because I was searching for answers to questions about counteracting misinformation. I got involved with the volunteers at Skeptical Science and even wrote a few articles for the website. I learned about the five techniques of science denial (FLICC), and, through continued learning and later teaching, I can now pretty much identify B***S*** whenever it comes my way. Mind you, it takes practice. And one still cannot know in most cases whether the purveyor of that BS does it purposefully (disinformation) or unknowingly (misinformation). And only recently did we get a straight answer to how disinformation has worked in practice:

Climate scientists have been dealing with either dis- or misinformation in the public sphere for decades. When Trump came around, then COVID-19 related misinformation, it was déjà vu all over again for most of us. And similar to decades earlier, there was not much scientists could really do other than keep debunking the myths and telling the truth, over and over again, trying to educate where possible, and eye-rolling and hoping for the best otherwise. Been there, done that.



2021 SkS Weekly Climate Change & Global Warming News Roundup #36

Posted on 5 September 2021 by BaerbelW

Listing of articles linked to on the Skeptical Science Facebook Page during the past week: Sun, August 29, 2021 through Sat, September 4, 2021

The following articles sparked above average interest during the week: From tweet to updated rebuttal - a little sagaThe Person Who Lies To You The Most…. Is You, Here’s what makes a new Amazon carbon study so unnerving, How to do your own research, and How easily the climate crisis can become global chaos.

Articles Linked to on Facebook



From tweet to updated rebuttal - a little saga

Posted on 3 September 2021 by BaerbelW

This blog post tells the little saga of how a tweet aimed at Repustar's @Fact Sparrow led to a quickly drafted new Fact Brief and how our internal review of the brief made it clear in turn that our related rebuttals were in dire need of updates as well.

The Tweet

On July 19, Spencer Fletcher tweeted the question "Why was there an ice age in the paleozoic era even though CO2 was 3000 ppm?" at @Fact Sparrow, Repustar's friendly fact delivery bot:


FactSparrow logged Fletcher's concern about this topic and promised to keep looking for more information. Acting on this promise included a notifcation from Repustar's staff to our team, to see if we - as one of Repustar's content partners - could help out with a new Fact Brief to answer Spencer's question.



Skeptical Science New Research for Week #35, 2021

Posted on 2 September 2021 by doug_bostrom

124 articles by 744 contributing authors

Physical science of climate change, effects

Tropical teleconnection impacts on Antarctic climate changes
Li et al. Nature Reviews Earth & Environment

Interpreting the Dependence of Cloud-Radiative Adjustment on Forcing Agent
Salvi et al. Geophysical Research Letters
Open Access 10.1029/2021gl093616

Observations of climate change, effects

The “Hockey Stick” imprint in Northwest African speleothems
Sha et al. Geophysical Research Letters

Toward an ice-free mountain range: demise of Pyrenean glaciers during 2011–2020
Vidaller et al. Geophysical Research Letters

Rapid rises in the magnitude and risk of extreme regional heat wave events in China
Wang & Yan Weather and Climate Extremes
Open Access 10.1016/j.wace.2021.100379

A Comparison of the Variability and Changes in Global Ocean Heat Content from Multiple Objective Analysis Products during the Argo Period
Liang et al. Journal of Climate

(provisional link) Novel and disappearing climates in the global surface ocean from 1800 to 2100

Extreme climatic characteristics near the coastline of the southeast region of Brazil in the last 40 years
de Oliveira et al. Theoretical and Applied Climatology
Open Access 10.1007/s00704-021-03711-z

The South Pacific Pressure Trend Dipole and the Southern Blob
Garreaud et al. Journal of Climate

Trends in soil temperature in the Icelandic highlands from 1977–2019
Petersen International Journal of Climatology

Observed and estimated consequences of climate change for the fire weather regime in the moist-temperate climate of the Czech Republic
Trnka et al. Agricultural and Forest Meteorology

Comprehensive observational features for the Kuroshio transport decreasing trend during a recent global warming hiatus
Liu et al. Geophysical Research Letters

Recurrent pattern of extreme fire weather in California
Son et al. Environmental Research Letters
Open Access 10.1088/1748-9326/ac1f44



Thinking is Power: Are you a Critical Thinker?

Posted on 1 September 2021 by Guest Author

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

Learn how to think, not what to think

Everyone thinks. And everyone thinks they’re good at thinking.

But good thinking is hard, and it doesn’t come naturally. It’s a skill that has to be learned and practiced. Our brains are adapted to keep us alive by making quick decisions to avoid predators and by forming strong emotional bonds with members of our tribes. Trusting that your brain inherently knows how to reason is a recipe for being misled. And it doesn’t matter how smart or educated you are. No one can lie to us better than we can.


Unfortunately, many of those who are most convinced that they are the true critical thinkers are actually doing the exact opposite. We all know who they are. They confidently air their opinions as fact and hide factually incorrect assertions behind an “opinion shield.” They oversimplify complex issues and are unwilling or unable to entertain nuance and detail. Due to a lack of substantive arguments, they resort to childish name-calling (eg “sheep,” and “fake news”), and proclaim that those who disagree with them are “stupid” and need to “think for themselves.” Ironically, they have inoculated themselves against critical thinking…..if you’re convinced you’re using “evidence” and “logic” and “know the truth,” why would you entertain the possibility that you’re wrong and need to learn new skills?



Here’s what makes a new Amazon carbon study so unnerving

Posted on 31 August 2021 by Guest Author

This is a re-post from Yale Climate Connections by Bob Henson

The sixth major assessment of climate science from the Intergovernmental Panel on Climate Change (IPCC) – which landed with an existential thud on our collective doorstep in August – confirms why we need to be profoundly concerned about parts of the Amazon shifting from a carbon sink to a carbon source, a finding reported in the journal Nature in June.

Just under half of the carbon dioxide (CO2) pumped out by human activity each year accumulates in Earth’s atmosphere. The other 56% is dutifully soaked up by the planet’s oceans and vegetation. That absorption has grown in remarkable sync with emissions themselves, the IPCC noted. There are year-to-year ups and downs, largely associated with El Niño and La Niña, but the average fraction of emitted CO2 going into ocean and land sinks has remained nearly constant for the past six decades.

It’s a prime example of what researchers like to call an “ecosystem service”: something our living planet does that happens to help us out. 

A partial ‘transition from carbon sink to source’

Ecologists and climate scientists have marveled at the planet’s ever-growing carbon sink even as they’ve worried about its ability to keep up with fossil fuel use. Now, a new Amazon study has yielded the starkest evidence to date of a region where the tide has turned and the landscape is consistently giving up more carbon than it can absorb. If additional land areas become sources instead of sinks over time, it could hobble our ability to slow and eventually reverse the nonstop buildup of CO2 in the atmosphere.

The transition from sink to source in the southeast Amazon became evident through monthly sampling via aircraft from 2010 through 2018: at four sites across the Amazon, as documented in the Nature study led by researcher Luciana Gatti of Brazil’s National Institute for Space Research (INPE). The southeast Amazon falls squarely in the long-time “arc of deforestation” that’s been pushing relentlessly toward the central Amazon.  

The other three areas, where forests are less depleted, were found to be either carbon-neutral or serving as weak carbon sinks. But in the southeast Amazon, deforestation and heating are pouring carbon into the atmosphere while cutting back on the region’s carbon absorption.

“Emissions come from fire initially, and later from the decomposition,” said Gatti in an interview. 



Catastrophic Hurricane Ida hits Louisiana with 150 mph winds

Posted on 30 August 2021 by Guest Author

This is a re-post from Yale Climate Connections by Jeff Masters and Bob Henson

Category 4 Hurricane Ida struck a catastrophic blow on Louisiana, making landfall at the key oil industry hub of Port Fourchon at 11:55 a.m. CDT August 29, with 150 mph winds and a central pressure of 930 mb. Remarkably, today is also the 16th anniversary of Hurricane Katrina’s devastating landfall in Louisiana and Mississippi in 2005. Katrina, the most expensive weather disaster in world history, at $176 billion, caused between 1085 and 1389 deaths.

Only four hurricanes (all Cat 5s) have made landfall in the contiguous U.S. with stronger winds than Ida, and Ida is tied with Laura of 2020 and the 1856 Last Island Hurricane as the strongest ever to hit Louisiana. As measured by central pressure at landfall, Ida ranks as the ninth-strongest to hit the contiguous U.S., and second-strongest to hit Louisiana. Only Hurricane Katrina of 2005, with a 920 mb pressure at landfall near Buras, had a lower pressure.

Ida is the second major hurricane of the 2021 season; Grace also became a major hurricane earlier this month as it hit Mexico. The most recent Atlantic hurricane season with two or more major hurricanes by August 29 was 2005 – the year of Katrina.

Ida put on a furious display of rapid intensification overnight, with the pressure dropping from 985mb to 929mb (a fall of 56 mb) in 24 hours. As documented by Sam Lillo (see Tweet below), only nine hurricanes on record in the Atlantic have done this, with Ida being the furthest north, and the one closest to a U.S. landfall. In one 12-hour period, Ida’s pressure fell by a remarkable 40 mb – the third fastest pressure fall observed in a Gulf of Mexico hurricane since 1979. Sea surface temperature of 30-31 degrees Celsius (86-88°F) and the warm Loop Current eddy that Ida passed over were both key factors in its intensification.
At landfall, Ida was undergoing an eyewall replacement cycle (ERC), which halted intensification just before landfall, causing the pressure to rise from 929 mb to 930 mb. The ERC kept the winds at the core from increasing further, but greatly broadened the area experiencing hurricane-force winds. This is overall a bad thing for Louisiana, as it will result in more wind damage.

According to Brian McNoldy, Ida’s Integrated Kinetic Energy (IKE, a measure of the total destructive power of hurricane, based on the size of its wind field) was 36 terajoules (TJ) at 11 a.m. EDT Sunday, an increase of 64% from the 22 TJ it had 24 hours previously. For comparison, Hurricane Katrina’s IKE at landfall was 113 TJ. Thus, Katrina’s surge had a lot more destructive power than Ida’s. However, Ida’s wind damage and fresh water flooding damage will likely exceed that of Katrina – particularly since Ida is hitting a key area of U.S infrastructure.



2021 SkS Weekly Climate Change & Global Warming News Roundup #35

Posted on 29 August 2021 by BaerbelW

Listing of articles linked to on the Skeptical Science Facebook Page during the past week: Sun, August 22, 2021 through Sat, August 28, 2021

The following articles sparked above average interest during the week: Eunice Newton Foote’s nearly forgotten discovery, As denying climate change becomes impossible, fossil-fuel interests pivot to 'carbon shaming', Cartoonists’ ‘Code Red’ caricatures of new IPCC report, and Europe’s July floods: So rare and extreme, they’re hard to study .

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