Millions of Americans are once again on the verge of dangerous heat. Last weekend, heat covered Europe and parts of France and Spain felt normal in July or August. High temperatures burned northern and central China, despite heavy rains causing floods in southern China. Some parts of India began to experience extraordinary heat in March, but the beginning of the monsoon rain brought some relief.
It is premature to say whether climate change is the direct cause of the serious heat waves in these four power plant economies.
Global warming is making extreme heat more common around the world, but tells scientists whether certain weather events are more likely or more intense due to human-induced warming. Therefore, a deeper analysis is needed. (Team of researchers who studied The devastating heat of this spring In India, climate change has been found to occur 30 times more likely. )
Still, co-occurrence heat waves hit specific groups in remote locations, which are increasing in frequency these days, for reasons related to jet streams and other rivers of air that affect meteorological systems around the world. It seems that.
Studies show North America, Europe and parts of Asia are linked this way. Scientists are still trying to determine how these patterns will change as the Earth warms further, but so far, in these places where much of the world’s economic activity is concentrated. At the same time, it means that extreme heat will continue to affect.
“To generate heat waves, we need heat, and we need an atmospheric circulation pattern that can store heat,” said Daniel E. Horton, a climate scientist at Northwestern University. With global warming, “we definitely get more heat,” he said. But climate change can also affect how this heat is distributed around the world by the airflows that circulate around the globe, he said.
Extreme weather events that occur simultaneously in many places are not limited to meteorological curiosity. Individual heat waves can lead to illness, death, wildfires and crop failures.Simultaneous things can be threatened World food supplyRussia’s invasion of Ukraine puts it in a dangerous tension this year.
Although the heat waves are intricately shaped Regional factors Scientists no longer doubt whether climate change is exacerbating them, such as urbanization and land use. Soon, the world’s most devastating heat waves may not have historical similarities from the days just before humans began to emit greenhouse gases into the atmosphere. Some scientists claimMakes the question of whether climate change is the main driving force obsolete.
Andrew Dessler, a climate scientist at the University of Texas A & M, has learned that the warming of decades has allowed scientists to know what is called a heat wave and what to treat as just a new normal in hot weather. He said it was already difficult.
For example, if the heat wave threshold is mercury above 100 degrees Fahrenheit for several days in a row, it is “not entirely unexpected,” Dr. Dessler said, occurring more regularly in multiple regions at once. I confirmed that. “Over time, more and more planets will experience these temperatures, eventually causing sufficient global warming, and all land areas of the mid-latitude northern hemisphere will exceed 100 degrees Celsius.” He said.
However, even when scientists examine the frequency with which the temperature exceeds a certain level with respect to the moving average, they find that the frequency of simultaneous heat waves has increased significantly.
1 Recent research This doubled the average number of days from May to September, when at least one large heat wave occurred in the Northern Hemisphere, from 73 days to about 152 days in the 1980s and 2010s. However, the number of days that two or more heat waves occurred was seven times higher, growing from 20 to about 143. This is almost every day from May to September.
Studies have also found that these simultaneous heat waves affect larger areas, become even more intense by the 2010s, and peak temperatures are nearly one-fifth higher than in the 1980s. Studies have shown that on average, 3.6 heat waves per day occurred on days when there was at least one large heat wave somewhere in the Northern Hemisphere.
Deepty Singh, a climate scientist at Washington State University and author of the study, said these “dramatic” increases were a surprise.
Dr. Singh and her co-authors also noted where simultaneous heat waves occurred most frequently during these 40 years. One pattern stood out. From 1979 to 2019, large heat waves often occurred simultaneously in eastern North America, Europe, Central Asia, and parts of East Asia. “It’s more than we can expect from the effects of global warming alone,” said Dr. Shin.
She said the study did not attempt to predict whether heat waves along this pattern would become more frequent as global warming continued.
Scientists are working to find out how the meandering jet streams that shaped the long weather patterns of billions of people will change in this era of warming. One factor is the rapid warming of the Arctic, which narrows the temperature difference between the northern and southern hemispheres of the northern hemisphere.How exactly this could be affecting Abnormal weather not yet Problem of discussion..
However, these temperature differences are important forces that drive the wind that keeps the meteorological system moving around the planet.As the temperature difference narrows, these airflows can slow down, he said. Kai Kornhuber, Climate scientist at Columbia University’s Lamont-Doherty Earth Observatory. This means that extreme events such as heat waves and heavy rains can last longer.
“The longer the heat wave, the more it pushes the natural and social systems to the edge,” said Dr. Kornhober.
Climate change has already meant that the world is experiencing more extreme weather events and at the same time more extreme weather events, he said. “These cycles change and work on it, and will make extreme conditions more serious and more frequent,” he said.