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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.


Cranky Uncle game now being translated

Posted on 23 July 2021 by John Cook

The Cranky Uncle game is now being translated into multiple languages, paving the way to building public resilience against misinformation across the world. So far, we have had volunteers offer to help translate the game into Danish, French, German, Italian, Polish, Portuguese, Romanian, Russian, and Ukrainian. But we are always looking for more volunteers both for additional languages and for extra helpers on current languages (it's a big game with a lot of content - many hands make light work). Sign up to help with the translation effort here!



Skeptical Science New Research for Week #29, 2021

Posted on 22 July 2021 by doug_bostrom

94 articles

Physical science of climate change, effects

Three flavors of radiative feedbacks and their implications for estimating Equilibrium Climate Sensitivity
Rugenstein & Armour Geophysical Research Letters
DOI: 10.1029/2021gl092983

Observations of climate change, effects

Multi-decadal change in western US nighttime vapor pressure deficit DOI: 10.1029/2021gl092983

Recent changes in the rain regime over the Mediterranean climate region of Israel
Drori et al Climatic Change
DOI: 10.1007/s10584-021-03161-6

Heat and freshwater changes in the Indian Ocean region
Ummenhofer et al Nature Reviews Earth & Environment
DOI: 10.1038/s43017-021-00192-6

Recent changes in global dryland temperature and precipitation
Daramola & Xu International Journal of Climatology
DOI: 10.1002/joc.7301

Climate hazards are threatening vulnerable migrants in Indian megacities
Hari et al Nature Climate Change
Open Access pdf DOI: 10.1038/s41558-021-01105-7

Faster decline and higher variability in the sea ice thickness of the marginal Arctic seas when accounting for dynamic snow cover
Mallett et al The Cryosphere
Open Access pdf DOI: 10.5194/tc-15-2429-2021

Changing status of tropical cyclones over the north Indian Ocean
Deshpande et al Climate Dynamics
DOI: 10.1007/s00382-021-05880-z

Period-Lengthening of the Mindanao Current Variability from the Long-Term Tide Gauge Sea Level Measurements DOI: 10.1007/s00382-021-05880-z

Increase in CO2 uptake capacity in the Arctic Chukchi Sea during summer revealed by satellite?based estimation DOI: 10.1007/s00382-021-05880-z

Contrasting temporal variations in responses of leaf unfolding to daytime and nighttime warming
Wang et al Global Change Biology
DOI: 10.1111/gcb.15777

Instrumentation & observational methods of climate change, effects

Climate Change Detection and Attribution using observed and simulated Tree-Ring Width
Franke et al
Open Access pdf DOI: 10.5194/cp-2021-80



As scientists have long predicted, warming is making heatwaves more deadly

Posted on 20 July 2021 by dana1981

This is a re-post from Yale Climate Connections

In its 2001 Third Assessment Report, the Intergovernmental Panel on Climate Change (IPCC) foresaw that global warming would lead to increasingly deadly heatwaves. “More hot days and heatwaves are very likely over nearly all land areas,” the world’s top climate scientists warned. “These increases are projected to be largest mainly in areas where soil moisture decreases occur.” 

 “The greatest increases in thermal stress are forecast for mid- to high-latitude (temperate) cities, especially in populations with non-adapted architecture and limited air conditioning,” they wrote at the time. “A number of U.S. cities would experience, on average, several hundred extra deaths each summer.”

Sound prescient? And familiar?  All too much so.

Twenty years later, it seems as though these climate scientists were gazing into a crystal ball rather than computer monitors. At the end of June 2021, the normally temperate Pacific Northwest experienced a record-shattering heatwave. The village of Lytton, in British Columbia,  set a new all-time Canadian temperature record of 49.6 degrees Celsius (121.3 degrees Fahrenheit) and was largely destroyed by a wildfire soon thereafter. Quillayute in the northwest corner of Washington, shattered its previous high temperature record by a full 11°F.

At least 800 deaths have so far been attributed to the extreme heat, and experts say they expect the final mortality tally to be considerably higher. Because of the region’s historically temperate weather, many homes lack air conditioning; residents were enveloped by temperatures well in excess of 100°F.

University of British Columbia marine biologist Christopher Harley estimates that the heatwave also caused over a billion marine wildlife deaths, as shells of dead mussels and clams coated rocks along the Pacific seashore.



The number of lives that clean energy could save, by U.S. state

Posted on 19 July 2021 by Guest Author

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

The United States can achieve net-zero carbon emissions by 2050 while creating half a million new jobs, modernizing the energy infrastructure, and avoiding hundreds of thousands of needless deaths, according to the comprehensive Net Zero America study by researchers at Princeton University.  The study concluded that the price tag for a major energy transition would be no more than the current system costs.

But the results of the Net Zero study are even better than they appear at first glance, because the transition to renewable energy can partly pay for itself, simply because replacing fossil fuels would mean fewer people die from air pollution.

Though the primary motivator in adopting clean energy is to reduce climate-warming greenhouse gas emissions, cleaner air is an enormous co-benefit. Phasing out coal, natural gas, and internal combustion engines has immediate, local, and concrete effects on air quality and human lives.

A recent study found that air pollution from fossil fuels kills 8 million people per year, worldwide. In the U.S. alone, a 2019 study estimated that fossil fuel use causes over 50,000 deaths and $445 billion in economic damage annually. (See also: Burning fossil fuels heats the climate. It also harms public health)

The economic and health burdens of air pollution are borne by individuals, families, and society, not by energy companies. The damage is socially and racially unjust, levying the heaviest toll on those least responsible for causing the problem. The fossil fuel industry’s ability to freely pollute and cause widespread degradation to public health is an example of a generous subsidy, because society bears the costs for oil, gas, and coal’s business model.

Fewer respirators, more solar panels

The Net Zero America report explores how decarbonizing the energy supply would affect jobs, public health, agriculture, and scores of other factors. The report was originally published in December 2020, and an updated, refined version of the study is soon to be released.

Erin Mayfield, a co-author of the study and an associate research scholar at Princeton who studies societal impacts of environmental policy, shared some of the new datasets with YCC. The numbers point to huge benefits of switching to clean energy, in terms of a dramatic reduction in air pollution.

The study produced several forecasts on improvements in air quality, showing effects of eliminating specific fuels in each of the 48 contiguous states every year from now until 2050. It’s a staggering amount of data, with a lot of good news in the results.

The Net Zero project modeled five possible pathways to decarbonize the energy supply. The scenario labeled E+ is sort of the middle-ground, and it’s the basis for the comparisons that follow.  E+ would phase out most coal by 2030, add massive amounts of renewable energy to the grid, and electrify transportation.

These improvements would save around 400,000 American lives by 2050, the study concludes. Breaking down these results by source reveals the deadliest types of pollution. Eliminating coal-burning is projected to save more than 100,000 lives between now and 2050, and switching road transportation from internal combustion to electric would result in around 98,000 avoided deaths. Phasing out natural gas saves more than 42,000 lives, and another 30,000 early deaths can be averted from winding down fossil fuel production.

Early deaths avoided

The map below illustrates how these public health gains would be distributed across the country.



2021 SkS Weekly Climate Change & Global Warming News Roundup #29

Posted on 18 July 2021 by BaerbelW

Listing of articles linked to on the Skeptical Science Facebook Page during the past week: Sun, July 11, 2021 through Sat, July 17, 2021

The following articles sparked above average interest during the week: Repustar Fact Brief: Is carbon dioxide incapable of warming the planet any more than it already has?, The problem with “doing your own research” (these two articles were even way above average as far as impressions, engagement and comments go!), A New Heat Wave Will Set Records Across the West This Weekend, Death Valley, California, breaks the all-time world heat record for the second year in a row, and Thawing Permafrost has Damaged the Trans-Alaska Pipeline and Poses an Ongoing Threat.

Articles Linked to on Facebook



Skeptical Science New Research for Week #28, 2021

Posted on 15 July 2021 by doug_bostrom

Decomposition of increasing atmospheric methane points to a decomposing Amazon

Methane is a powerful greenhouse gas, relatively short-lived in the atmosphere compared to CO2 but far more effective at "helping" to retain heat, gram-for-gram. With its radiative effects "super powers," methane is a potentially dramatic additional contributor to disastrous levels of warming of Earth's surface and it's for that reason that numerous articles in the New Research "GHG sources & sinks, flux" section treat various matters of methane and its direction as a constituent of the atmosphere, on a perennial basis. Modern concentrations of methane in the atmosphere are about twice what they were several hundred years ago, pretty much exclusively thanks to direct and indirect effects of human activity on the surface of our planet. After growth coming nearly to a halt in the early part of this century, methane has again been rising at concerning rates and researchers are scurrying to identify possible sources for this bulge.

In their article Large and increasing methane emissions from eastern Amazonia derived from satellite data, 2010–2018 (open access) just published in Atmospheric Chemistry and Physics, Wilson et al use direct sampling backed up by confirmatory calculations to identify South America's Amazon  River basin as a likely significant contributor to recent acceleration of atmospheric methane content. They attribute this to increases of temperature in conjunction with flooding events, something a layperson following the trend of other articles in this section of New Research will find intuitively plausible. 

This is an article with impressively deep foundations, meaning that its introductory section and underpinnings of citations of previous research are particularly rewarding for getting a grip on the general topic. 

From the concluding words of the abstract, these authors appear to have found a major component of recent increases in methane content of our air: 

Our results show that the Amazon alone was responsible for 24 ± 18 % of the total global increase in CH4 flux during the study period, and it may contribute further in future due to its sensitivity to temperature changes.

Sea level rise combines with lunar wobbles to create soggy 2030s for US seaboards

"Freeboard" is a nautical term to describe "extra" height of a ship's weather deck above the water level. It's a bad idea to load a ship so heavily as to diminish freeboard to dangerous levels, because this leaves no margin for handling rough weather or other contingencies. It's not a perfect analogy but in the case of the freeboard of the US seaboard we're increasing the water level below our "deck" such that an upcoming peculiarity in the Moon's orbit about Earth will likely cause massive and prolonged flooding in susceptible areas of the US coast (and of course coastlines elsewhere) beginning in the 2030s and extending for quite a few years. If we'd paid attention to science 20-30 years ago and in particular if the US public had not been subject to a prolonged, concerted campaign of lying and disinformation about climate change, we might have been facing only one factor in the upcoming unpleasantness, the natural variability of the Moon's orbit. Instead, we've set the scene for a sinking, as described in Rapid increases and extreme months in projections of United States high-tide flooding (open access) by Thompson et al and just published in Nature Climate Change. The abstract: 

Coastal locations around the United States, particularly along the Atlantic coast, are experiencing recurrent flooding at high tide. Continued sea-level rise (SLR) will exacerbate the issue where present, and many more locations will begin to experience recurrent high-tide flooding (HTF) in the coming decades. Here we use established SLR scenarios and flooding thresholds to demonstrate how the combined effects of SLR and nodal cycle modulations of tidal amplitude lead to acute inflections in projections of future HTF. The mid-2030s, in particular, may see the onset of rapid increases in the frequency of HTF in multiple US coastal regions. We also show how annual cycles and sea-level anomalies lead to extreme seasons or months during which many days of HTF cluster together. Clustering can lead to critical frequencies of HTF occurring during monthly or seasonal periods one to two decades prior to being expected on an annual basis. 



Death Valley, California, breaks the all-time world heat record for the second year in a row

Posted on 14 July 2021 by Guest Author

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

For the second consecutive year, Death Valley, California, has set a world record for the hottest reliably measured temperature in Earth’s history.

Death Valley National Park’s Furnace Creek Visitor Center hit an astonishing 130.0 degrees Fahrenheit (54.4°C) on Friday afternoon, July 9, 2021, beating the previous world record of 129.9 degrees Fahrenheit (54.4°C), set there on August 16, 2020. For perspective, according to What’s Cooking America, a medium-rare steak is cooked to an internal temperature of 130-135°F.

According to weather records expert Christopher Burt, who wrote the comprehensive weather records book Extreme Weather, and extreme weather expert Maximiliano Herrera, who tweets under the Twitter handle Extreme Temperatures Around the World, the observation, if confirmed, would be the hottest reliably recorded temperature in world history.

Cautions about the record

Friday’s measurement will have to undergo review by the World Meteorological Organization (WMO) before being declared officially valid. Two possible areas of concern are that the temperatures at Furnace Creek showed a steep jump during the afternoon, and the nearby Stovepipe Wells station was considerably cooler, topping out at 122.6 degrees Fahrenheit (50.3°C). (See the raw high-resolution Furnace Creek data here by choosing a time up to six days in the past from the drop-down menu, then choosing “Decoded Data”.) WMO has not yet certified last year’s 129.9 degrees Fahrenheit (54.4°C) reading on August 16, 2020 at Furnace Creek as valid, so there may be a long wait. Fortunately, we’ll have excellent independent verification of this year’s measurement thanks to a temporary thermometer set up at the site in May by Campbell Scientific.

Climatologist William Reid, an expert on Death Valley meteorology who has written extensively about the site, cautioned that an increase in vegetation and structures built in the vicinity of the Furnace Creek site in recent decades has allowed the station to record hotter temperatures.

“An increase in vegetation and some man-made structures not too far south of the station have resulted in poorer ventilation through the station area. Since the station is above a bare and sandy surface, hot air along the ground during afternoon sunshine is less effectively mixed away from the instrumentation. The result is higher temperature readings during the afternoon comparably,” Reid wrote. “I figure that most summer maximums at Death Valley today are a couple of degrees higher because of the poorer station exposure. A day that hits 125 degrees today probably would have only been as high as 122-123 degrees before 1980.”

Figure 1. Hourly maximum temperature at Death Valley National Park’s Furnace Creek Visitor Center July 6-12, 2021. (Image credit: NOAA)

Official world record remains 134°F at Furnace Creek in 1913



Additional Fact Briefs published on Repustar

Posted on 13 July 2021 by BaerbelW

With an initial batch of eight published Fact Briefs we announced our partnership with the fact-checking organization Repustar at the end of April 2021. Since then, work has progressed in the background and seven more Fact Briefs have been published and are now available for quick rebuttals.


Do ice core records showing that warming preceded CO2 rise cast doubt on greenhouse warming?

NO - Antarctic ice core records dating back 800,000 years suggest that increases in carbon dioxide lagged behind increases in temperature by a couple of hundred years. This observation has been used by some to incorrectly claim that modern CO2 emissions cannot be causing a rise in temperature. This misconception is based on the false dichotomy that warming is either driven by CO2 or CO2 is driven by warming. In reality, both are true. Read more ...

Is carbon dioxide incapable of warming the planet any more than it already has?

NO - As CO2 accumulates in the atmosphere, trapping and re-radiating heat, Earth continues to warm. Rising CO2 acts like a blanket, reducing the amount of energy escaping into space and causing the lower atmosphere, and surface, to warm.

A long-standing misconception is that the greenhouse effect is “saturated,” suggesting that adding more CO2 will not increase the amount of energy being trapped. This view fails to recognize that the atmosphere consists of multiple layers.. Read more ...

Do natural climate cycles disprove that modern global warming is caused by humans?

NO - During Earth’s last glacial period between 120,000 and 11,500 years ago, a number of approximately 1,500-year temperature cycles occurred. Also known as Dansgaard-Deschger events, the cycles caused a transfer of heat between the northern and southern hemispheres, producing a “seesaw effect”: when one hemisphere cooled, the other warmed. Read more ...



The making of a one-of-a-kind climate change PR professional

Posted on 12 July 2021 by Guest Author

This is a re-post from Yale Climate Connections by James Hoggan

In the world of environmental communication, we are learning as we go. For years, we thought facts and outrage changed minds in ways we now know they don’t. We need to explore reliable new ways to speak, listen, and connect in the face of environmental disinformation and polarization.

For that we need ongoing research that helps educate us as it explores and advances the principles of effective science communication and highlights the harms of anti-environmentalism.

My own journey from corporate PR consultant to co-founder of a new media website investigating climate change disinformation was eye-opening. We launched DeSmogBlog in January 2006 to “clear up the PR pollution that clouds climate science.” We wrote about Darth Vader PR campaigns in the US, Canada, Australia, and the UK, largely funded by the coal and oil industries. Finding myself in the midst of a nasty international dispute about the climate crisis, I realized the strategies used to mislead people with anti-science propaganda and anti-environmentalism are much more developed and robust than those used to educate people about science and the environment.

My interest in environmental disinformation started in 2003 when I was invited to join the board of the David Suzuki Foundation, Canada’s best-known science-based environmental organization. Consultants at my public relations firm thought accepting would be a mistake. They questioned the wisdom of associating with environmental activists. We worked for the establishment. Environmentalists make the establishment nervous.

Suzuki Foundation board members had concerns of their own. Wasn’t public relations spin part of the problem? Wasn’t it responsible for much of the public confusion? It’s hard to argue with that. Public relations does have its “dark side.” Without bad actors manipulating public opinion, our path toward solutions would be quicker: We’d see more light, less heat.

Even though I owned a highly successful PR shop in Vancouver, I didn’t see myself as part of that dark side. But I can see why some Suzuki board members might disagree: We represented the establishment on difficult public issues, including the environment: governments, hospitals, universities, big business (especially real estate development), banks, biotech, forestry, mining, oil and gas, and even the cruise ship business.

When I accepted the appointment, I didn’t know a lot about the environmental challenges the world was facing. But when I join a board, I read my board package. I attend board meetings. I listen to briefings and read reports.

When Al Gore came to a board dinner in the spring of 2007, I paid attention. And given chances to talk to famous scientists about climate disruption, I jumped.

Two pieces of writing around that time upended my worldview: a New Yorker series called ‘The Climate of Man’ by Elizabeth Kolbert, which in 2006 became a best-selling book, Field Notes From a Catastrophe; and Boiling Point in 2004 by former Boston Globe reporter Ross Gelbspan. These books opened my eyes to how serious the climate crisis is.

Over time, I realized that environmentalists are not crazy or even radicals. They’re very often telling the truth: Humans are rapidly destroying the oceans, driving record levels of species to extinction, and dangerously overheating the climate. Environmental collapse isn’t just a future risk. It is well underway.



2021 SkS Weekly Climate Change & Global Warming News Roundup #28

Posted on 11 July 2021 by BaerbelW

Listing of articles linked to on the Skeptical Science Facebook Page during the past week: Sun, July 4, 2021 through Sat, July 10, 2021

The following articles sparked above average interest during the week: What’s the carbon footprint of a wind turbine?, Analysts dissect historic Pacific Northwest ‘heat dome’, A guide to prebunking: a promising way to inoculate against misinformation, Hundreds died in the West's heat wave last week. Now another one is gearing up, An Indigenous Group’s Objection to Geoengineering Spurs a Debate About Social Justice in Climate Science, Western Heat Wave ‘Virtually Impossible’ without Climate Change, Australia govt to appeal court ruling on climate change duty of care.

Articles Linked to on Facebook



Halfway point in this year's run of Denial101x - 5 more months to go!

Posted on 9 July 2021 by BaerbelW

This year's self-paced run of our free online course, Making Sense of Climate Science Denial, started on February 9, 2021 and it will be available until December 14, 2021. This means that we reached the halfway point with 5 months already behind and 5 more months ahead of us!  For the current run we are closing in on 1,000 registered participants and it's not too late to join them as you'll have ample time to work through the material at your own pace. The following graphic is a quick summary of our MOOC, shared at this year's General Assembly of the European Geosciences Union (vEGU21) in a session about climate literacy:

SummarySlide Denial101x

Abstract EGU-8576 - Using an interdisciplinary MOOC to teach climate science and science communication to a global classroomfull presentation (7MB)



Skeptical Science New Research for Week #27, 2021

Posted on 8 July 2021 by doug_bostrom

Zigzagging to zero: Wandel Sea old ice

A plethora of previous research and observation has pointed to an ultimate demise of multi-year ice in the Artic, with a shrinking time horizon. "Old ice" is expected to mount a final resistance in redoubts such as the Wandel Sea. We're seeing the last act of this drama playing out, as illustrated by a synthesis of observations and modeling by Schweiger et al in our "highlight" article for this week,  Accelerated sea ice loss in the Wandel Sea points to a change in the Arctic’s Last Ice Area (open access, PDF). In a nutshell: secular change in climate behavior combines with variabilty to dictate a wavering path to "no more old ice," with the date of "done" looming ever closer. It's not possible to improve on a well-executed abstract for a concise summary: 

The Arctic Ocean’s Wandel Sea is the easternmost sector of the Last Ice Area, where thick, old sea ice is expected to endure longer than elsewhere. Nevertheless, in August 2020 the area experienced record-low sea ice concentration. Here we use satellite data and sea ice model experiments to determine what caused this record sea ice minimum. In our simulations there was a multi-year sea-ice thinning trend due to climate change. Natural climate variability expressed as wind-forced ice advection and subsequent melt added to this trend. In spring 2020, the Wandel Sea had a mixture of both thin and—unusual for recent years— thick ice, but this thick ice was not sufficiently widespread to prevent the summer sea ice concentration minimum. With continued thinning, more frequent low summer sea ice events are expected. We suggest that the Last Ice Area, an important refuge for ice-dependent species, is less resilient to warming than previously thought.

108 articles

Physical science of climate change, effects

‘Simpson's Law’ and the Spectral Cancellation of Climate Feedbacks
Jeevanjee et al Geophysical Research Letters
Open Access pdf DOI: 10.1002/essoar.10506744.1 10.1002/essoar.10506744.2

CO2-equivalence metrics for surface albedo change based on the radiative forcing concept: a critical review DOI: 10.1002/essoar.10506744.1 10.1002/essoar.10506744.2 10.1029/2021gl093699



Analysts dissect historic Pacific Northwest ‘heat dome’

Posted on 7 July 2021 by greenman3610

This is a re-post from Yale Climate Connections by Peter Sinclair

“In a climate-changed world, the things that once seemed impossible are not just possible, they are probable.”

Those words come from on-air weather and climate change expert Jeff Berardelli wrapping up a piece for CBSN.

Berardelli had told the CBS cable network anchor that the temperature in the Pacific Northwest has increased 3 to 4o F in the past century, leading to expectations in the future for seven to 10 days per year of temperatures over 100oF. He attributed the historic high-temperature readings across the U.S Pacific Northwest and western Canada to an “omega block”:  a “blocking pattern or traffic jam in the atmosphere” that impedes strong weather systems from moving rapidly from west to east:  Instead, they ‘get stuck’ in place.”

“Almost unbelievable, even for meteorologists,” Berardelli says of the persistent heat that plagued the region June 26-28.

“We can certainly say that heat waves are increasing as a result of climate change,” says Steve Vavrus of the University of Wisconsin. Colorado assistant state climatologist Becky Bolinger points to “a time 30 years ago, 40 years ago, when it was uncommon to get 100-degree days every single year, and that is much more common now.”  They and other scientists in the video find a link to climate change.  

Kai Kornhuber of Columbia University says in the latest “This is Not Cool” video that the result is that “a weather pattern that was harmless in the past is now leading to very extreme conditions.”



Deciphering the rise and fall of Antarctic sea ice extent

Posted on 6 July 2021 by Guest Author

This is a re-post from Carbon Brief by Dr Clare Eayrs and Prof David Holland

The sharp decline in Arctic sea ice over recent decades has become one of the most enduring images of the Earth’s warming climate. Yet, at the same time, the sea ice changes at the Earth’s south pole have been much less clear-cut.

Antarctic sea ice extent increased gradually over much of the satellite record (1979 to present), reaching successive record highs in 2012-14. Yet, 2016 saw the beginning of the most pronounced fall in sea ice cover ever observed. Over the three years that followed, the precipitous drop in Antarctic sea ice was equivalent to 30 years of sea ice loss in the Arctic.

These fluctuations led the Intergovernmental Panel on Climate Change (IPCC) to conclude in its 2019 special report on the ocean and cryosphere that Antarctic sea ice extent “overall has had no statistically significant trend” due to “contrasting regional signals and large interannual variability”.

Our perspective paper, published in Nature Geoscience, draws on recent research to examine what the recent dramatic loss in Antarctic sea ice cover reveals about the processes that control sea ice in the region. 

We find that the swift and unexpected sea ice decline was mostly caused by an exceptional weakening of the westerly winds that encircle the continent of Antarctica. 

While the sea ice seems to be bouncing back, coverage is still well below the 2014 record high. Sea ice cover in this region is clearly vulnerable to rapid change. However, if we are to project future change accurately, we need to pinpoint the processes both near and far that influence the winds around Antarctica.



Western Canada burns and deaths mount after world’s most extreme heat wave in modern history

Posted on 5 July 2021 by Guest Author

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

Hundreds of North Americans – and perhaps many more yet to be tallied – have died of heat-related illness over the past week after a mind-boggling heat wave struck the U.S. Pacific Northwest U.S. and far southwest Canada. It’s virtually certain to be the deadliest weather event on record for the region. The unprecedented death toll is the result of a heat onslaught more intense by some measures than anything in global records, yet very much in line with the expected impacts of a human-warmed climate.

The poster community of this horrific episode has to be Lytton, British Columbia. The town broke Canada’s longstanding all-time national high temperature of 45 degrees Celsius (113 degrees Fahrenheit) with a high of 46.6°C (116°F) on Sunday, June 27. The next day brought 47.9°C (118.2°F), and Tuesday a stunning 49.6°C (121°F).

The intense heat flash-dried the rugged, forested landscape, and wildfires mushroomed across the area on Wednesday, June 30. By evening, the entire town of Lytton was under mandatory evacuation orders, and Mayor Jan Polderman told CBC News that “the whole town is on fire.” Most homes in Lytton have been destroyed, according to provincial authorities.

The lighting from the dry thunderstorms (pyrocumulonimbus) that developed was so intense that over 700,000 intracloud and cloud-to-ground lightning flashes were recorded in 15 hours, including more than 100,000 cloud-to-ground strikes. That’s about 5% of the total number of lightning flashes Canada typically sees in an entire year (see Tweet below).

The fires have generated huge clouds of choking smoke that put air quality in the red “Unhealthy” range in Kamloops, British Columbia, on Thursday.



2021 SkS Weekly Climate Change & Global Warming News Roundup #27

Posted on 4 July 2021 by BaerbelW

Listing of articles linked to on the Skeptical Science Facebook Page during the past week: Sun, June 27, 2021 through Sat, July 3, 2021

The following articles sparked above average interest during the week: The cool, lush Pacific Northwest roasts in Death Valley-like temperatures, Record-breaking temperatures mean we must change the way we talk about the climate emergency, The scientists hired by big oil who predicted the climate crisis long ago, How to Live in a Climate ‘Permanent Emergency’ and All the right words on climate have already been said.

Articles Linked to on Facebook



‘Tis the season’? Learn how change is in the air

Posted on 1 July 2021 by Guest Author

This is a re-post from Yale Climate Connections by SueEllen Campbell

On June 6, 1857, Henry David Thoreau wrote this in his journal: “Our thoughts and sentiments answer to the revolutions of the seasons, as two cog-wheels fit into each other.” It’s true: the seasons we know are both material and cultural, both collective and personal. We expect them to stay reasonably stable through our lifetimes and we layer them with all kinds of memories and expectations. 

The June solstice will arrive as usual on the 20th, despite our having caused Earth’s axis to move a little bit (through climate change and perhaps groundwater pumping). But – as a direct result of our putting more CO2 into the air – other aspects of our seasons are breaking with their past. 

We’ll focus first on the planet’s temperate zones.

According to the American Geophysical Union (AGU), “Northern Hemisphere summers may last nearly half the year by 2100.” Note the excellent graphic of the projected shifting of season dates.

You can find an excellent set of summaries and specific data (intended for reporters) at Climate Central and at the EPA’s newly-restored set of climate indicators (see seasonal temperatures and growing seasons).

Winters are warmer, even when they seem cold to us, as explained by Mark Kaufman in Mashable

Springs are earlier. See, for instance, this story (Jason Samenow, Washington Post) about Japan’s cherry blossom records and this EPA record of ice breakup on Alaska’s rivers. 



Skeptical Science New Research for Week #26, 2021

Posted on 30 June 2021 by doug_bostrom

Not the negative feedback we're looking for

When discussing climate change we hear more about positive feedbacks such as decreasing Arctic Ocean albedo than we do negative feedbacks, which are few and far between. Nikolaos ChristidisMark McCarthy and Peter Stott manage to pin down one of these rare beasts and put it under the microscope, in Recent decreases in domestic energy consumption in the United Kingdom attributed to human influence on the climate. Due to heating and cooling demands, utility energy consumption tends to form a "U" shape, with the left or right "legs" of the "U" following the proportionality of cold versus hot weather driving heating or cooling loads, cooling being less of a universal feature than heating. The authors find that in the United Kingdom energy consumption for heating has measurably dropped "thanks" to a warming climate, resulting in a reduction of household demand amounting to some 1,400kWh per year. This effect is conspicuous in the UK given the low penetration of and requirement for domestic cooling. While this nets enough savings on utility bills to buy a few bags of groceries the trade does not seem worth it, and of course in other geographic domestic contexts featuring a "U" dominated by cooling the opposite effect will pertain. It's a thought-provoking publication for the layperson, dealing as it does with familiariities while neatly illustrating how warming our climate can produce less obvious and sometimes bizarre effects. 

Meanwhile, the blinkered view

Economic and other "externalities" increasingly inform public policy as our realization is cemented that nothing on Earth can be truly "thrown away" or disposed of short of shooting it into deep space and that in a world supporting 7 billion humans virtually every human action leaves a "footprint" even as we walk away. In healthy democracies policy responsive to reality requires impetus and demand from the ultimate authority— voters. Should not enough voters have a factual grip on what shapes their world, policy to optimize our situation will suffer commensurate with the demand failure. In the face of this and with such an abundance of people stressing the capacity of the planet, full accounting for and acknowledgement of our impact becomes very important as a technical matter.  It's for this reason that research such as Climate change denial is associated with diminished sensitivity in internalizing environmental externalities (open access) particularly deserves our heed. Our way to a better future lies in better understanding of how we see our world and think about it, so this article by Berger & Wyss is a welcome addition to a crucially important research domain. From the abstract: 

Our results show that climate change scepticism predicts self-interested choices and showcases that sceptics have an insensitive acceptance of emissions, reaping benefits no matter how large the climate cost are or how small the personal benefits become. 

This may sound condemnatory but the authors are only expressing their findings in clinical language. For us laypersons,"clinical" suggests that a remedy for the malady might be found. Now that we see the problem, we can figure out how to address it. 


In order to slightly level a schedule including peaks that are too high, New Research will be moving to Thursday publication commencing with the next edition. 



The cool, lush Pacific Northwest roasts in Death Valley-like temperatures

Posted on 29 June 2021 by Guest Author

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

A diabolical mix of heat-producing ingredients came together from Saturday to Monday, June 26-28, to brew up the most spectacular – and dangerous – heat wave ever observed in the Pacific Northwest and southwest Canada. Millions of residents from Portland to Vancouver eastward suffered in widespread heat exceeding 100 degrees Fahrenheit (38 degrees Celsius), with temperatures well above 110°F in some places.

All-time records were toppled in dozens of towns and cities, in some cases by 4°F or more. That’s well above the roughly 2°F of warming observed regionally and globally over the past century. Such an outcome is in line with recent studies indicating that high-end heat extremes may increase more rapidly than overall temperature in some areas as human-produced global warming continues.

There are too many jaw-dropping records from this still-unfolding heat wave for a comprehensive listing right now. To cite just a few of the standouts:

•  Portland, Oregon, broke its longstanding all-time record high (107°F from 1965 and 1981) on three days in a row – a stunning feat for any all-time record –  with highs of 108°F on Saturday, June 26; 112°F on Sunday; and a preliminary 115°F on Monday. That 115°F is equal to the average daily high on June 28 at Death Valley, California.

• Oregon’s state capital of Salem hit a mind-boggling preliminary high of 117°F. If confirmed, that will tie the all-time state record high set on July 27, 1939, at Umatilla and on August 4, 1998, at Pelton Dam. Likewise, the preliminary high of 118°F at Columbia Gorge Regional Airport ties the Washington state record set on August 5, 1961, at Burbank (Ice Harbor Dam).

•  Seattle, Washington, broke its official all-time high (103°F at Sea-Tac airport in 2009) with 104°F on Sunday, then topped that reading with a preliminary 107°F on Monday.

•  Quillayute, Washington, broke its official all-time high by a truly astonishing 11°F, after hitting 110°F on Monday (old record: 99°F on August 9, 1981). Quillayute is located near the lush Hoh Rain Forest on the Olympic Peninsula, just three miles from the Pacific Ocean.

•  Canada broke its all-time national temperature record with a preliminary high of 46.6°C (116°F) in Lytton on Sunday, June 27, then beat the record again with a preliminary 47.9°C (118.2°F) on Monday. The old record was 45.0°C (113°F) from July 5, 1937. The high at Lytton is also the world’s highest temperature ever recorded north of latitude 50°N, according to international weather records expert Maximiliano Herrera.



SkS Analogy 22 - Energy SeaSaw: Part III

Posted on 28 June 2021 by Evan, jg

Tag Line

Illustrating what causes complex temperature patterns.

Climate Science

What causes the complicated patterns in measured temperature anomalies from year to year? Why is there so much variation, and do you need a Ph.D. in climate science to understand what creates such erratic patterns in measured temperature anomalies, such as those shown in Fig. 1? Although the plot of temperature anomaly vs. year might appear random, there are many known processes that create the detailed, complicated structure, such as energy exchange between the oceans and the atmosphere described in Energy SeaSaw Part I.

NASA GISTEMP v4 data set from 1970 to 2020 showing regular ups and down of temperature anomalies with a clear, upward temperature trend

 Figure 1. Temperature anomalies from 1970 to 2020 from the NASA GISTEMP v4 data set.

It is clear from Fig. 1 that temperature anomalies are increasing, but from year to year there are significant ups and downs. Another way to get a feel for how regular processes create what appears to be random variations on an otherwise increasing trend, consider the evolution of the financial assets of a typical family over a single year. Figure 2 shows the hypothetical ups and downs superimposed on top of steadily increasing assets.



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