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Intensifying Cycle of Extreme Heat And Drought Grips Europe

2024-12-19 09:27:11 Finance

For Chloe Brimicombe, a climate researcher at the University of Graz in Austria, the heat and drought statistics in today’s new European State of the Climate Report for 2022 evoked grim memories of the deadly heat waves last summer in Reading, her hometown in the United Kingdom, where people died from heat exposure while waiting for help.

“People were dying from heat stress before the ambulance got there, in some cases, because they couldn’t describe the severity of their symptoms, because they didn’t know that it was heat,” said Brimicombe. Doctors also reported seeing more breastfeeding mothers who didn’t realize their infants were dehydrating in the extreme heat, she added.

The European Union’s Copernicus Climate Change Service said in the report that Europe has already warmed more than 2.2 degrees Celsius (3.9 degrees Fahrenheit) from the pre-fossil fuel era, compared to the global average of 1.2 degrees Celsius (2.2 degrees Fahrenheit). In 2022, Southern Europe saw a record number of summer days with dangerous heat stress, as well as record-breaking marine heatwaves in the Mediterranean, its report said. 

Last summer was Europe’s warmest on record, and heat waves killed more than 15,000 people, nearly 10 times more than the devastating floods in Pakistan, making them by far the deadliest meteorological events of the year. But many countries, even in highly developed regions like the European Union, still lack adequate heat health plans, Brimicombe said.

Last summer’s deaths in Europe show there are still dangerous gaps in the public understanding of rapidly emerging climate threats, as well critical weaknesses in adapting to those threats, she added. 

“We know that there’s an underreporting of impacts, especially related to heat,” she said, referring to recent research. “It would be great to fill that gap as a next step in these reports.”

The worst heatwave was in July, when the temperature in the U.K. passed 40 degrees Celsius for the first time on record, and Brimicombe said the normally cool, green campus at the University of Reading felt like the desert.

“It was very weird,” she said. “It was almost as dusty as a desert, as well, because we had the drought along with the heat. And the fire service in London was saying it was their busiest day since World War II, with wildfires actually encroaching on houses, which was quite unusual before this. And we are going to see more of this, but we are not prepared for all of this at once.”

River discharge was the second-lowest on record across Europe. It was the sixth straight year of below average flows. Surface soil moisture, critical for plants, was the second-lowest measured in the last 50 years. The warm and dry conditions also contributed to one of the most intense wildfire seasons on record.

Persistent heat waves and lack of rainfall in Europe in 2022 led to exceptionally low river flows across most of the continent. Credit: European State of the Climate Report for 2022

The report also shows how the impacts can intensify each other in a spiral of worsening extremes. The lack of winter snow last year followed by record summer warmth melted Europe’s glaciers faster than ever before, thinning them by 11.5 feet on average. 

Somewhat paradoxically, the record glacier melt may have been the only thing that sustained flows in some European rivers last summer during months of exceptionally low rainfall. But most glaciers in the Alps will be gone by the end of this century, wiping out that frozen water reserve, which will throttle summer flows even lower.

All the glacial ice that was lost in Europe last year would add up to an ice cube the size of central Paris, towering 3 miles high, and all the climate signs point toward even hotter years becoming more frequent in the future, said Samantha Burgess, Copernicus’ deputy director. 

“Imagine having a deck of cards and picking one at random, with red as warm years and black as cool,” she said. “Climate change is removing the black cards from the deck and adding extra red ones.” 

The data from 2022, she added, show that many southern Europeans faced some level of heat stress on 70 to 100 days last summer.

And that means “it’s not enough to just do a transition to net zero,” Brimicombe said. “You still need adaptation, because it’s too late to stop future heatwaves. People will still die as a result of heat unless we adapt, as well. We can’t just keep being old school and saying that, if we transition to net zero, everything is going to be solved. That’s not true for heat waves.”

Returning Rains Won’t Alleviate Drought Woes

It’s not true for drought, either, said Robert Vautard, a senior climate scientist who studies regional extremes at the French National Centre for Scientific Research and was a coordinating lead author of a recent report from the Intergovernmental Panel on Climate Change (IPCC). 

Europe has warmed at twice the global average rate the past two decades, and that warming is enough to dry up soil and vegetation, but when you combine the warmth with many successive months of below normal rainfall, including during the winter, “the situation becomes critical,” he said.

The new Copernicus report details the near record low flows in nearly all European rivers at the end of last summer. Winter brought little relief, so reservoirs are drying up, with critical water shortages and potentially catastrophic impacts to agriculture expected in large parts of western and southern Europe, including important breadbasket areas in France and Spain. 

And while water emergencies may seem sudden to some, it shouldn’t have come as a surprise to governments if they were paying attention to recent major global climate reports and research, he said. 

Climate attribution studies in 2017, 2019 and again last year show the clear links between human-caused climate change and heatwaves. A 2020 study suggested a mechanism for that change, as the warming caused by greenhouse gases shifts the Northern Hemisphere jet stream—which carries rainy storm systems west to east—poleward in the summer, shunting moisture away from central Europe toward the Arctic.

“In Western and Central Europe, you get more rain in winter, and less rain in summer, but temperature has the biggest overall effect for the future,” he said. “What we are really concerned with is the increase in temperature.” 

Vautard said the recent extremes should not be mistaken for anything other than what they are: clear signs of worsening climate impacts caused by increasing concentrations of greenhouse gases. And it’s a warning sign for other parts of the world. 

“The two regions for which we have confidence in the long term drought signal attributable to climate change,” he said, “are the Mediterranean and Western Europe, and the Western U.S., especially the Southwest.”

The report was released just after one of the earliest major wildfires on record burned in southern France, and Burgess said the data show that, as the planet warms, the normal climate is shifting.

“The chance of snowless mountains and lower rainfall increases,” she said. “We can’t stop these changes, but we can limit the impacts by reducing greenhouse gas emissions rapidly.”

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