New study finds a significant increase in rainfall across the United States

A new study published in the Geophysical Research Letters found that rainfall has become more intense across the United States over the past few decades.

The study, titled “Observed changes in daily precipitation intensity in the United States,” compared rainfall over time in 17 different climate regions and found statistically significant increases in precipitation throughout. One of these regions included an area east of the Rocky Mountains where, according to the paper, there had been a 5% increase in rainfall. Researchers believe that this change will negatively affect agriculture and infrastructure in vulnerable areas across the country.

The study’s senior author, Daniel Horton, is an Assistant Professor at Weinberg College’s Department of Earth and Planetary Sciences.

“When people study how climate change has affected weather, they often look at extreme weather events like floods, heatwaves and droughts,” said Horton. “For this particular study, we wanted to look at the non-extreme events, which are, by definition, much more common. What we found is pretty simple: When it rains now, it rains more.”

Professor Horton also leads the Climate Change Research Group (CCRG) at Northwestern University. The CCRG uses numerical models, environmental observations, statistical analyses, and machine learning techniques to ask questions pertinent to Earth’s (and other planets’) climates.

Learn more in Northwestern Now’s article, “It’s raining harder in the U.S.”