In Europe, climate change is increasing the number of days with extreme heat and decreasing the number of days with extreme cold, according to a new study published by the American Geophysical Union.
Study lead author Ruth Lorenz is a climate scientist at the Swiss Federal Institute of Technology in Zurich, Switzerland.
“Even at this regional scale over Europe, we can see that these trends are much larger than what we would expect from natural variability. That’s really a signal from climate change,” said Lorenz.
While it has been well established that climate change is warming Europe, scientists have been primarily focused on long-term changes in extreme temperatures.
For the new investigation, experts compared observational data to climate models used for regional projections to analyze the top one percent of heat extremes and the top one percent of cold extremes across Europe from 1950 to 2018.
The study revealed that some areas of Europe are warming faster, and heat waves are happening more frequently, than climate models had projected.
According to the study authors, there were drastically different temperature trends across individual regions, which makes it difficult to compare the average European temperatures to the extremes observed at specific stations.
The researchers pinpointed regions that experienced higher extremes – as well as other regions that experienced lower extremes – than what was expected.
Geert Jan van Oldenborgh is a climate analyst at the Royal Netherlands Meteorological Institute in the Netherlands, who was not involved in the study.
“In the Netherlands, Belgium, France, the model trends are about two times lower than the observed trends,” said van Oldenborgh. “We’re reaching new records faster than you’d expect.”
The number of days with extreme heat has tripled in Europe since 1950, and the summers are now hotter overall. Temperatures hit record highs this summer, exceeding 114.8 degrees Fahrenheit in southern France.
Furthermore, there are now less than half the number of extreme cold days during the winter compared to 1950, and the later part of the year has grown significantly warmer.
More than 90 percent of the weather stations produced data that correlated with climate warming. The researchers explained that this percentage is too high to be a result of natural climate variability.
The study authors also noted that European summers and winters will only grow hotter in the coming years as climate change accelerates, impacting populations that are unprepared for rising temperatures.
Extreme heat poses a dangerous risk to human health, putting a major strain on the body that can cause heat exhaustion or heat stroke.
“Lots of people don’t have air conditioning for instance and it makes this really important,” said Lorenz. “We expected results based on modeling studies but it’s the first time we see it in what we’ve observed so far.”
The study is published in the journal American Geophysical Union.
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By Chrissy Sexton, Earth.com Staff Writer
Paid for by Earth.com
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