Mar 21, 2019

25 States Are at Risk of Serious Flooding This Spring, U.S. Forecast Says

Hamburg, IA
John Schwartz
New York Times
Flooding in Hamburg, Iowa, on Monday. Credit: Tim Gruber for The New York Times
Flooding in Hamburg, Iowa, on Monday. Credit: Tim Gruber for The New York Times

Vast areas of the United States are at risk of flooding this spring, even as Nebraska and other Midwestern states are already reeling from record-breaking late-winter floods, federal scientists said on Thursday.


“The flooding this year could be worse than anything we’ve seen in recent years, even worse than the historic floods of 1993 and 2011,” said Mary C. Erickson, deputy director of the National Weather Service, in a conference call with reporters. The major flooding this month in Nebraska, Minnesota, Iowa and elsewhere is “a preview of what we expect throughout the rest of the spring,” she said.


The projections were part of NOAA’s annual “Spring Outlook,” though the language of the 2019 report carried greater urgency than usual. That is not surprising, since the basins of the Upper Mississippi and the Red River of the North have already been hit with rain and snow this spring of up to twice normal levels.

“We’ve set over 30 records in Nebraska, Iowa and South Dakota” in the last week alone, said Kevin Low, a scientist with the National Weather Service’s Missouri River Basin Forecast Center. That flooding has devastated farmers and ranchers across the region, put communities like Hamburg, Iowa, underwater, and wiped out roads and bridges in others.


More rainfall in the Midwest is a predictable consequence of climate change, according to the most recent National Climate Assessment, which was produced last year by 13 federal agencies. A warmer atmosphere can hold more moisture, which comes down as precipitation.


Andrew Dessler, a professor of atmospheric sciences at Texas A&M University, said that understanding the role of climate change in weather events like the Nebraska floods required applying the tools of a growing field known as attribution science...

Humans have loaded so much planet-warming carbon dioxide into the atmosphere that “the starting assumption has to be that climate change is affecting everything” to some extent, he said.

“The real question isn’t, ‘Is climate change playing a role?’” Dr. Dessler said. “It’s, ‘How big a role is climate change playing, and what is the role?’”