Eva Deschamps / August 16, 2022
The United States will see the development of an extreme heat belt from Louisiana in the south to Lake Michigan in the north, crossing the Midwest, according to a new report released Monday.
This area, home to more than 100 million Americans and covering a quarter of the country, will experience at least one day of extreme heat per year in 2053, with a felt temperature of more than 51 degrees Celsius, according to the report by the nonprofit First Street Foundation.
Currently, this is the case for only about 50 U.S. counties with 8 million people. In 30 years, it will affect more than 1,000 counties, including the states of Texas, Louisiana, Arkansas, Missouri, Illinois, Iowa, Indiana, and even southern Wisconsin.
The Midwest is particularly hard hit because of its distance from the sea, the report notes, although other smaller areas on the East Coast and in southern California are also affected.
Heat is the number one killer weather phenomenon in the United States, ahead of floods or hurricanes. It can lead to hospitalizations and serious complications. It is particularly dangerous in places not used to high heat -- like the northern United States. The First Street Foundation based its projections on a moderate scenario of the United Nations climate experts (IPCC), in which greenhouse gas emissions peak in the 2040s before declining.
Beyond these extreme temperatures, the entire country must warm up. On average, the 7 hottest days of the year locally today will become the 18 hottest days in 30 years.
The number of dangerous days, defined in the report as days when the temperature approaches 38°C felt, will increase in the south of the country. Around the Gulf of Mexico, many areas currently have about 100 days per year at this temperature, but are expected to have more than 120 by 2053.
Heat waves, which see these very hot days follow one another without interruption, are also expected to lengthen: in thirty years, large areas of Texas and Florida may experience up to 70 consecutive days around 38°C felt. The report assessed these changes at a very fine scale, so that residents, businesses and officials can anticipate their response locally.
We need to prepare for the inevitable, Matthew Eby, founder of First Street Foundation, said in a statement. The consequences are going to be dire.