For parts of Europe, it’s as if summer just won’t end.
Countries from Spain and France to as far north as Norway and Sweden are experiencing unseasonably warm temperatures for this time of year.
The balmy conditions in western and central Europe follow a summer marked by intense heat waves, widespread drought and severe wildfires across the continent — adding to concerns about the consequences already being felt from climate change.
In Morón de la Frontera, in southern Spain, temperatures last week soared above 95 degrees Fahrenheit, conditions more common during the summer. In France, some regions experienced temperatures nearly 20 degrees F above normal for late October and early November.
Even some Nordic countries haven’t been immune to the recent warm spell — the Swedish city of Kristianstad hit 67 degrees F less than a week ago, Agence France-Presse reported.
“It’s really a continentwide event,” said Andrew Pershing, the director of climate science at Climate Central, a nonprofit research organization headquartered in Princeton, New Jersey. “These temperatures are not just unusual but kind of remarkable for this time of year.”
The unseasonable warmth owes to a kink in the jet stream, a ribbon of fast-moving air that flows west to east over the Northern Hemisphere and controls weather systems. The resulting trough over the eastern part of the North Atlantic Ocean allowed southwesterly winds to move warmer-than-usual air over Europe, said Christopher O’Reilly, a research fellow in the meteorology department at the University of Reading in the United Kingdom.
The jet stream is powered by temperature differences between the cooler Arctic region to the north and warmer air masses to the south. When the band of air is wavier than normal, it can move warm air northward or conversely cause polar air to reach farther south. Changes in the jet stream’s behavior can significantly affect weather systems around the world.
Some scientists have been investigating what impact — if any — global warming has on the jet stream, but the links, if they exist, aren’t yet well understood. Still, it’s clear that climate change is amplifying the consequences of jet stream anomalies, O’Reilly said.
“This is even true for the relatively recent past,” he said in an email. “For example, October 2001 had a similar trough orientation of the jet stream over the North Atlantic, with southwesterly winds bringing warmer air and associated anomalously high temperatures over western/central Europe — but the temperatures were clearly lower than this year and this is due to the overall warming of the climate system.”
A report published Wednesday by the World Meteorological Organization found that temperatures in Europe have increased at more than twice the global average over the past three decades. From 1991 to 2021, temperatures in Europe warmed at an average rate of about 0.9 degrees F per decade, with implications for societies, ecosystems and economies across the continent, the agency said.
“Europe presents a live picture of a warming world and reminds us that even well prepared societies are not safe from impacts of extreme weather events,” Petteri Taalas, the meteorological organization’s secretary-general, said in a statement.
At Climate Central, Pershing and his colleagues created a tool to help people visualize the effects of such warming over time. The group’s Climate Shift Index, which launched last week, reflects the change in daily average temperatures for 1,000 cities around the world over the previous 365 days.
The tool offers a way to track in real time how much climate change contributes to conditions at those locations.
“You can just really see how different people’s experience with climate change is depending on where you live and depending on the season,” Pershing said.
Across western and central Europe, unseasonably warm temperatures are expected to persist for the next two weeks. While it’s unusual, the anomalous warm spell fits within the bigger pattern of global warming, Pershing said.
“These are the conditions we expect to see more of in the coming years,” he said. “These are the conditions that we have to prepare our cities, our families, our businesses for in the future.”