by First the river arrived in Texas. Then the rain fell hard over North Carolina, New Mexico and Illinois.
In less than a week there were at least four rainfall events of 1 on-1,000 years in the United States-inense Distributions that are thought to have about a chance of 0.1% to happen in a certain year.
“Each of these intense rainfall events has a low chance of appearing in a certain year,” said Kristina Dahl, vice-president for science at the non-profit organization Climate Central, “so to see events that are historical and record-breaking in several parts of the country in the course of a week is even more alarming.”
It is the kind of statistics, said different experts, which is both an eye opening and is probably more common due to climate change.
At least 120 people were killed last week in six provinces in the Hill Country region of Central Texas, after heavy rainfall caused catastrophic floods. The river Guadalupe, near Kerrville, rose more than 20 feet in 90 minutes during the storm, roads away and caused widespread destruction.
Days later, on Sunday, soaked parts of Tropical Storm Chantal from North Carolina. Extensive floods were reported over the central part of the state, with some areas in just 24 hours getting almost 12 centimeters of rain. Local officials still confirm the total number of deaths due to the floods, while the region is under a different flood watch on Thursday.
In New Mexico on Tuesday, at least three people were killed by devastating flash flashes that sweeped by the remote mountain village of Ruidoso, about 180 miles south of Albuquerque.
And in Chicago that same day 5 centimeters of rain fell over Garfield Park in just 90 minutes, which gave rise to several rescues on the west side of the city.
Experts said that although floods of 1 in 1,000 years are statistically rare, a certain number takes place every year in the United States.
“The chance is 0.1% for your location every year, so it is very unlikely where you are, but some of them will happen somewhere every year,” said Russ Schumacher, director of the Colorado Climate Center at the Colorado State University and the state climatologist.
Climate change makes these kinds of extreme flood events probably more often, he said.
It is often difficult to discharge the precise influence that climate change had on individual weather events, but scientists agree that serious storms are more likely in a warming world – along with more intense rainfall.
“This is one of the areas where Attribution Science Solider is, because the underlying physics is relatively easy,” said Schumacher.
A warmer atmosphere can retain more water, allowing storms to dump huge amounts of rain over the country. Studies have shown that for every degree Fahrenheit that the planet warms up, the atmosphere can contain about 3% to 4% more moisture.
“It is a mathematical certainty that as the atmosphere retains more water, it can also discharge more water in an immediate way,” said Dave Goochis, a hydrometeorologist who is the head of forecast services at air observatories in the air, a company with headquarters in Mammoth Lakes, those measures and models of Snow- and Waterellen.
But terrain can also be an important factor during heavy rainfall, said GoChis.
In Texas, for example, the hills and canyons of the area make it sensitive to floods. Thin soil on top of a layer of rock also limits how much water can be absorbed in the soil, said GoChis.
In New Mexico, the village of Ruidoso was destroyed last year by forest fires, causing burns of scars that increased the drain and raised the risks of floods.
The events of the past week have revealed the devastating effects of climate change in extreme weather – and the need to protect communities, both before and after these events take place, said Dahl of Climate Central.
Recovery efforts can take years, she said, and other consequences, including public health, can linger much longer.
“These events come and go in the news, and before you know it, we are on our way to the next,” said Dahl. “It is easy to forget that for the people experience this, it is really healing for a year.”
This article was originally published on nbcnews.com
