| | Extreme Temperature Diary- Friday July 11th, 2025/Main Topic: European June Heatwave Was a Catastrophic CAT5 – Guy On Climate
Dear Diary. Obviously, my foray into categorizing and naming heatwaves is just an experiment to show that it can be done to highlight these systems for public awareness, which could save some lives. Since there are very many of these systems outside of the United States, almost too many to keep up with these days, I am just naming major heatwaves in the United States.
One heatwave more than just deserved a name back in June that raged across Europe, which killed more than 2000 people by last count. By my guidelines since it killed more than 1000 people it was a catastrophic CAT5. Essentially, this European heatwave was roaring while the eastern U.S. went through historic CAT4 Heatwave Shell. The worst European heatwave I know of occurred during most of the summer of 2003, which killed more than 10,000, and if I had a CAT6 in my system, that would be it.
In any case, attribution studies indicate that the June 2025 European heatwave was enhanced by our long-term use of fossil fuels. Here are more details from the Guardian:
twitter.com
For a statistical chart that is a great graphic that I did not include, please hit the following link:
theguardian.com
extreme heat
Climate breakdown tripled death toll in Europe’s June heatwave, study findsHeat caused 2,300 deaths across 12 cities, of which 1,500 were down to climate crisis, scientists say A woman protects herself from the sun near the Bridge of Sighs in Venice last month. Photograph: Marco Bertorello/AFP/Getty Images
Extreme heat
Ajit Niranjan Europe environment correspondent
Wed 9 Jul 2025
Planet-heating pollution tripled the death toll from the “quietly devastating” heatwave that seared Europe at the end of June, early analysis covering a dozen cities has found, as experts warned of a worsening health crisis that is being overlooked.
Scientists estimate that high heat killed 2,300 people across 12 major cities as temperatures soared across Europe between 23 June and 2 July. They attributed 1,500 of the deaths to climate breakdown, which has heated the planet and made the worst extremes even hotter.
Milan was the hardest-hit city in absolute terms, with 317 out of 499 heat deaths attributed to climate breakdown, followed by Paris and Barcelona. London had 273 heat deaths, 171 of which the researchers attributed to human influence on the climate.
“This study demonstrates why heatwaves are known as silent killers,” said Malcolm Mistry, an epidemiologist at the London School of Hygiene & Tropical Medicine and co-author of the study. “While a handful of deaths have been reported in Spain, France and Italy, thousands more people are expected to have died as a result of the blistering temperatures.”
The rapid analysis from the World Weather Attribution group, which used established methods but has not yet been submitted for peer review, blames climate breakdown for two-thirds of the deaths.
Older people had the highest mortality, the study found, with 88% of the climate-driven deaths in people over the age of 65. The researchers said extreme heat was an “underappreciated” threat as most victims died out of public view in homes and hospitals, and with little media coverage.
“Heatwaves don’t leave a trail of destruction like wildfires or storms,” said Ben Clarke, a climate scientist at Imperial College London and co-author of the study. “Their impacts are mostly invisible but quietly devastating. A change of just 2 or 3C can mean the difference between life and death for thousands of people.”
The scientists used epidemiological models to estimate heat-related mortality in cities such as Paris, London, Madrid and Rome over a 10-day-period, and compared the death toll with that of a hypothetical world in which humans had not heated the planet by burning fossil fuels or destroying nature.
They cautioned that the relationships between temperature and death they used in their models were derived from local mortality data up to 2019, and so may not fully capture how people in each city have adapted to hotter weather over time.
They found climate breakdown pushed temperatures in some cities up to 4C higher, resulting in 1,500 extra deaths. The death toll was greater than that of other recent weather disasters that were made worse by fossil fuel pollution, such as the floods that killed 224 people in Spain in 2024 and the floods that killed 243 people across north-west Europe in 2021.
Previous studies have estimated that about 44,000 people die from heat in Europe each year, averaged over the past few decades. The scientists suggested the vast death toll of 2,300 people from a single heatwave in just 12 cities could make this summer particularly dangerous.
The EU’s Earth observation service, Copernicus, said last month was the third hottest June on record globally and that an “exceptional” marine heatwave developed in the western Mediterranean. The average daily sea surface temperature was the highest ever recorded for the region in June at 27C.
Copernicus also found a large increase in dangerous “tropical nights”, where night-time temperatures do not drop below 20C and people struggle to rest. Parts of Spain had as many as 24 tropical nights last month, 18 more than the average for June.
Samantha Burgess, a deputy director of the Copernicus climate change service, said the record temperatures in the Mediterranean made the heat stress that large parts of Europe experienced “much more intense”.
She said: “In a warming world, heatwaves are likely to become more frequent, more intense and impact more people across Europe.”
Analysis by Mercator Ocean, a nonprofit research organisation that runs Copernicus’s marine service, found nearly two-thirds of the Mediterranean was hit by marine heatwaves that were classed as strong or worse, the greatest extent ever recorded.
The high temperatures are known to disturb fish and kill some of the plants they feed on. Mass-mortality events have repeatedly struck the Mediterranean in recent years as marine heatwaves have grown hotter.
Karina Von Schuckmann, a scientist at Mercator Ocean, said: “One particular aspect that is quite concerning … is this repeat emergence of heat stress. If you repeat the heat stress over time, the vulnerability of these specific ecosystems increases.”
Here are more “ET’s” recorded from around the planet the last couple of days, their consequences, and some extreme temperature outlooks, as well as any extreme precipitation reports:
twitter.com
twitter.com
twitter.com
twitter.com
twitter.com
twitter.com
Climate Central: "Dangerous, climate change-boosted heat will impact the Western U.S. this week. Up to 43 million people will experience extreme heat that's at least 3x more likely due to human-caused climate change. For 25+ million, this unusual heat is at least 5x more likely. ??/1" — Bluesky
Dr. Jeff Masters: "The standout U.S. weather event for June was the heat wave of June 22-25; 8 states set all-time June high temperature records. yaleclimateconnections.org/2025/07/june..." — Bluesky
LakeBrowser: "Accelerating increase in the duration of heatwaves under global warming www.nature.com/articles/s41..." — Bluesky
The Nature Conservancy: "Regardless of where we live or how we vote, extreme weather puts us all at risk: and we know, without a shadow of a doubt, that it's getting worse due to climate change. A must-read piece from @katharinehayhoe.com." — Bluesky
Tracey Stephens: ""Warmer temperatures allow for the atmosphere to hold more water vapor, producing heavier rainfalls". Burning fossil fuels causes warmer temps. #StopBigOil #EndFossilFuels #CleanEnergyNow @greenfaith.bsky.social @katharinehayhoe.com" — Bluesky
Lily Dove: "Big up to @rdzombak.bsky.social for bringing eyes to this story. ?? So many people beyond my little cohort of fellows are impacted by slowdowns at NOAA. America is rapidly losing footing as a leader in climate science and we all are paying the cost." — Bluesky
Andrew Dessler: "Jim Hansen has a substack. His first post is good. Jim is one of the greatest climate scientists and his work in the 1980s through 2000s set up the frameworks that we still use today for thinking about forcing and feedbacks. open.substack.com/pub/jimehans..." — Bluesky
Center for Conflict and Cooperation at NYU: "Climate change is one of the most pressing crises looming over humanity. But what are the best predictors of climate-friendly beliefs, and how do they compare across countries? In our latest paper, we use machine learning to explore this question across 55 countries. Read below:" — Bluesky
Nature Geoscience: "?? Article: Mid-Holocene and the future warming induces a North Pacific response resulting in sustained winter precipitation deficits and drought over the Southwestern United States. www.nature.com/articles/s41..." — Bluesky
Keith McNeill: "“We can’t talk about protecting human rights from climate change without talking about – and taking urgent action on – phasing out fossil fuels.” – Elisa Morgera, UN special rapporteur #GlobalCarbonFeeAndDividendPetition www.climatechangenews.com/2025/07/09/u..." — Bluesky
Katharine Hayhoe: "Newspaper coverage of climate change around the globe dropped 6% from May to June 2025 -- and by 28% compared to June 2024, despite increasing frequency and severity of climate-fueled extreme weather events. Read more from the @media-climate.bsky.social here: mecco.colorado.edu/summaries/is..." — Bluesky
Katharine Hayhoe: "A thermometer doesn't give a different number if you're red, blue--or green. Nor does a hurricane knock on your door and ask who you voted for in the last election before it destroys your home. Experts agree: it's real, it's us, it's serious and there are solutions. We just need to implement them!" — Bluesky
Katharine Hayhoe: "Hope "doesn’t mean denying hard truths — it means holding them in one hand and doing the work with the other." Love this new definition by RAI Energy's Kristina Jansen wrote (on LI, so sharing here) after reflecting on what I write and say about this in my newsletter :)" — Bluesky
Silicon Valley North on X: "Petition to sign to remind the #EPA Administrator of his sworn oath, which, naturally he refuses to do under Trump, because @epaleezeldin is a piece of work. t.co; / X
Michael Lowry: "One of the comments that struck me in yesterday's call is how NOAA cuts are already affecting forecast capabilities. According to 45-year hurricane veteran Dr. Frank Marks, staff needed to fly NOAA Hurricane Hunters is down 50% this year. He's volunteering to pick up shifts to keep them running ??" — Bluesky
dan solomon: "aaron parsley’s incredible, horrifying, somehow beautiful essay about what happened to him and his family last weekend on the guadalupe river is one of the best and most moving things you will read this year (content note: child loss) www.texasmonthly.com/news-politic..." — Bluesky
Michael Lowry: "Important post from @franklinjamesl.bsky.social this afternoon about what the proposed NOAA cuts would mean for hurricane forecasting (from the person who oversaw the NHC's hurricane forecasters) open.substack.com/pub/franklin..." — Bluesky
Dr. Jeff Masters: "Remarkable! "Purposely driving or walking into floodwaters accounts for more than 86% of total U.S. flood fatalities." Flash flooding the most deadly flood type; males more likely to be killed in floods than females; ages <30 the most vulnerable to floods. www.mdpi.com/2073-4441/13..." — Bluesky
Dr. Jeff Masters: "If you want to follow all the ways our weather forecasts are worsening because of NOAA’s troubles, you should follow @dinahvp.bsky.social. She documents at least 5 ways serious degradation is occurring." — Bluesky
Dr. Jeff Masters: "If you want to follow all the ways our weather forecasts are worsening because of NOAA’s troubles, you should follow @dinahvp.bsky.social. She documents at least 5 ways serious degradation is occurring." — Bluesky
Katharine Hayhoe: "Flash flooding for second July in a row in Ruidoso NM, just over the border from Texas. Flood risk is already high due to the topography and the more climate change loads the atmosphere with water vapor, the more rain gets dumped, putting more people in harms way ??" — Bluesky
NPR: "An Oklahoma City TV station says it's weather radar was damaged by an individual and that an anti-government militia took responsibility, claiming that radar is used to control the weather. (via @kosuradio.bsky.social)" — Bluesky
Katharine Hayhoe: "It might sound counterintuitive when those who reject human-caused climate change believe we’re intensifying weather extremes via secret expts—but here’s the difference. A: We’re responsible, so we all have to fix it B: We’re not, so it’s not our fault 99% of climate denial is solution aversion!" — Bluesky
Michael Noble: "A ray of hope in a dark time. @billmckibben.bsky.social delivers." — Bluesky
Katharine Hayhoe: "Cleaning up the minerals we need for clean energy, record-breaking carbon pollution, and how each of us can scale clean energy adoption--this week's newsletter connects the dots between science, policy, and action. Read the full edition of the newsletter here!" — Bluesky
Aquatic (palaeo)biology lab ????????: "Thread Our new paper shows aquatic insects shrink & develop faster as water warms. That weakens their role in ecosystems, hurt by global insect decline. Why shrink? Larvae can’t get enough O2. @ebdonana.bsky.social @csic.es @jeffvandermeer.bsky.social @katharinehayhoe.com ?? doi.org/10.1111/een...." — Bluesky |
|
