Publication Date March 7, 2018 | InsideClimate News

Sea Level Rise Will Rapidly Worsen Coastal Flooding in Coming Decades, NOAA Warns

United States
The nuisance flooding that accompanies seasonal high tides in parts of the Miami area will become more common as sea level rises. Photo: Joe Raedle, Getty Images
The nuisance flooding that accompanies seasonal high tides in parts of the Miami area will become more common as sea level rises. Photo: Joe Raedle, Getty Images

Coastal communities should expect much more frequent flooding in coming decades as sea levels rise, according to a new federal report. Many places that are dry now could flood every day by the end of the century.

The report, published by the National Oceanic and Atmospheric Administration, projects the impact of sea level rise on coastal flooding along the nation's shorelines and says it's already having an effect, particularly on the East Coast. In the Southeast, the average number of days with high-tide floods has more than doubled since 2000, to three per year, while the number in the Northeast has increased by about 75 percent, to six per year.

"We're seeing an accelerated increase up and down most of the Atlantic Seaboard," said William V. Sweet, an oceanographer at NOAA and the lead author of the report. "That's not a good place to be, because impacts are going to become chronic rather quickly."

While Miami currently experiences only a few days of high-tide flooding per year, for example, it should expect 10 days each year by the early 2030s under an intermediate scenario for sea level rise. Just a decade later, that number could triple. And flooding would likely occur every other day by 2060.

Flood Risk Varies Region to Region

It doesn't take a scientist to tell you that rising seas will worsen coastal flooding, but the new report shows how the effects will vary greatly across different regions.

The Northeast currently experiences the most frequent flooding, largely because of regular winter storms—including a recent series of storms that has caused flood damage across the region.