An unseasonably early heat wave is bearing down on Europe this week, bringing record-setting temperatures to countries like France and Germany, according to the World Meteorological Organization.
Temperatures are expected to reach and surpass 104 degrees Fahrenheit (40 degrees Celsius) in much of western Europe, including France, which will contend with a peak of 113 degrees Fahrenheit (45C) on June 28. The last time France faced a comparable heat wave was in 2003, when temperatures reached 111 degrees Fahrenheit (43.9C) and 15,000 people died.
Officials throughout France have put several regions on an “orange” heat alert notice, which discourages people from spending too much time outside in the sun, and urges them to be highly attuned to potential health complications while exposed to the weather.
Severe heat waves can cause heat exhaustion, cramps, dehydration, and heat stroke. The very young, the very old, people who work outside, and people living in poverty who may not have access to cooling devices are especially vulnerable to the effects of heat waves. During severe heat waves, dozens and even hundreds of people in urban areas can rapidly die.
Early heat waves are especially dangerous because people have not yet had time to gradually adjust to the warmer weather, according to the World Health Organization.
The unusual heat wave in western Europe reflects the shifting realities of climate change. Since 2000, 18 of the 19 hottest years in recorded history have occurred. Countries prone to high temperatures such as India have faced scorching heat events in recent years, and cooler countries like Finland have also experienced debilitating hot spells. Even the Arctic has experienced record-setting heat waves.
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“Globally, these extreme temperatures are five times more likely to occur now as they would be in an unchanged climate [in pre-industrial times],” Dim Coumou, a scientist at Germany’s Potsdam Institute for Climate Impact Research, told Time.
“There’s never a single cause for an extreme weather event,” he said. "But we have very strong evidence from many types of studies — based on both observations and climate models — that these heat waves are strongly on the rise as a result of climate change.”
As greenhouse gas emissions continue to accumulate in the atmosphere, more heat from the sun is being trapped on Earth and the normal environmental buffers that would otherwise mitigate this heat are being overwhelmed. For example, the world’s oceans absorb the vast majority of the excess heat trapped by greenhouse gas emissions, but they’re becoming too hot for marine life; this also creates feedback loops that melt sea ice at higher-than-normal rates.
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The jet stream, which sends cooling air from the polar regions to the rest of the world, is fragmenting; soil, forests, and plant life that cool down ecosystems are degrading; and water sources that could be used to cool down populations are becoming scarce. All of these phenomena are exacerbating hotter conditions globally.
In the decades ahead, the planet’s warming is expected to have brutal consequences. In the United States, for example, thousands of additional people are expected to die during intense heat waves than at current levels.
The Paris climate agreement seeks to keep global temperatures from rising by more than 2 degrees Celsius above pre-industrial levels. Even if that goal is achieved, dangerous heat waves like the one in western Europe will continue to occur with alarming regularity, but without urgent climate action, they could be increasingly severe.