A new report from the National Oceanic and Atmospheric Administration (NOAA) finds that the frequency of coastal flooding at high tide across the U.S. has doubled in the past 30 years. This type of flooding, often referred to as “sunny day flooding,” occurs without the presence of a storm; the floodwaters simply arrive with the high tide. In 2017, there was an average of six high-tide flooding days, a record high, in each of the 98 coastal areas studied. Researchers expect the next two years to bring much of the same, while the long-term forecast, exacerbated by rising sea levels and increased occurrences of extreme weather, is more foreboding.

Traffic jam on a flooded road

In 2017, the Northeast and the Gulf of Mexico regions were the most affected by high tide coastal flooding. Boston, Massachusetts and Atlantic City, New Jersey experienced 22 days of flooding, while Galveston, Texas, in addition to being hit by Hurricane Harvey, was affected by 18 days of high tide coastal flooding. Because of cyclical climate conditions, NOAA expects the next two years to be as bad or worse for coastal flooding in at least half of the 98 areas featured in the study.

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“Breaking of annual flood records is to be expected next year and for decades to come as sea levels rise, and likely at an accelerated rate,” the report reads. “Though year-to-year and regional variability exists, the underlying trend is quite clear: due to sea level rise, the national average frequency of high tide flooding is double what it was 30 years ago.”

Hurricanes and extreme weather may cause acute incidents of devastation, but the report suggests that mundane high tide coastal flooding represents a different, more pervasive kind of threat. “We need to rethink our relationship with the coastline because it’s going to be retreating for the foreseeable future,” geologist Andrea Dutton told the Guardian. “We need to take this report as a warning to prepare ourselves, or we will just sit around and wait for disaster to happen.” Despite the imminent threat, the U.S. currently has no federal plan to adapt to rising sea levels and increased flooding.

+ NOAA

Via The Guardian

Images via Depositphotos (1, 2)