Extreme precipitation patterns shifting in the United States

A study led by researchers at the Lamont-Doherty Earth Observatory, part of the Columbia Climate School, has identified shifting patterns in extreme precipitation events in the United States. Published in Geophysical Research Letters, the research examines the spatial footprints of storms rather than focusing solely on individual weather station statistics.

The findings reveal a complex trend: while the average weather station in the eastern United States has recorded an increasing number of days with extreme rainfall since 1980, the overall frequency of extreme rainfall events may actually be decreasing. This discrepancy is explained by the spatial scale of the storms, noting that large-area events, such as Hurricane Ida in 2021, can cause widespread destruction across entire states, whereas smaller-area events result in more localized flash flooding.