This summer, three separate downpours in three states over an eight-day period washed away homes, destroyed crops and killed at least 39 people.
Intense rains in Missouri, Kentucky and Illinois broke century-old records and destroyed swaths of communities, prompting warnings from climate experts, who said the intensity and frequency of heavy rains would increase probably as the Earth continues to warm.
Parts of southeast and central Illinois recorded more rain in 36 hours on Monday and Tuesday than they usually get for the entire month of August. In eastern Kentucky and central Appalachia, precipitation from July 26 to July 30 exceeded 600 percent of normal. In Missouri, rainfall records were wiped out during a two-day downpour last week.
No storms can be directly attributed to climate change without further analysis, but the intensity of these downpours is consistent with how global warming has caused an increase in the frequency of extreme precipitation events. A warmer Earth has more water in the atmosphere, which leads to more severe thunderstorms.
“We predict that these types of events could become even more frequent in the future or even more extreme in the future as the earth continues to warm, which means that this is a kind of call for action. action that climate change is here,” Kevin said. Reed, an associate professor in the School of Marine and Atmospheric Sciences at Stony Brook University in New York. “It’s not a problem in 50 years. It’s a problem now.
“Historically unprecedented” amounts of rain.
The pressure on cities and states to prepare for these events was evident in Kentucky, where at least 37 people died, and in Missouri, where two people died.
In Kentucky, rainfall at times exceeded four inches per hour, the National Weather Service said, and washed out homes and parts of some communities.
In four days, between 14 and 16 inches of rain fell in a narrow band across the eastern part of the state, according to weather service radar estimates. He said it was “historically unprecedented” and there was less than a 1 in 1,000 chance of so much rain falling in any given year.
Earlier that week in east-central Missouri, the Weather Service said 7.68 inches of rain fell over a six-hour period, an event that also had a 0.1% chance of occurring. in a given year.
The downpour hit the St. Louis area and surrounding areas particularly hard, forcing residents to flee their homes in inflatable boats after roads flooded with water.
The July 25-26 flood was the most prolific rainfall event in St. Louis since records began in 1874, according to the weather service. About 25% of the region’s normal annual precipitation fell in about 12 hours.
Neil Fox, a professor of atmospheric sciences at the University of Missouri, said the heavy rains in Missouri were caused by thunderstorms developing over and over again in the same area, what meteorologists call forming. The formation is a common cause of heavy rain and also brought downpours in Illinois and Kentucky.
“The number of records being broken is like somebody breaking the 100m world record by one second or something,” Prof Fox said. “This is an incredible increase from the previous record.”
Rainfall in Illinois this week was less and no deaths were reported, but the deluge caused flash flooding and damaged crops. The weather service said the highest rainfall measured during this storm was seven inches, which has a 1 to 2 percent chance of occurring in any given year.
“We usually get a little over three inches in August, and we got five to seven inches just in the first two days here in August,” said Nicole Albano, a meteorologist with the National Weather Service office in Lincoln, Ill. “It’s quite substantial.”
The United States and other parts of the world have seen an increase in the frequency of extreme thunderstorms due to climate change, caused by the burning of fossil fuels like oil and gas. The frequency of these heavy downpours is likely to increase as warming continues.
“We also expect the heaviest possible precipitation events at a given location to become heavier as the temperature increases,” said Angeline Pendergrass, an assistant professor at Cornell University in Ithaca, NY, who studies extreme rainfall. “That means we should expect more rainfall records to be broken than we would without global warming.”