The U.S. endured a record number of days of high-tide flooding last year largely due to rising seas from man-made climate change, the National Oceanic and Atmospheric Administration said.
Across the USA, coastal cities and towns racked up a combined 520 days with high-tide floods, far above the annual average of 275 days over the past couple decades, NOAA Oceanographer William Sweet said. That broke the previous record set only a year earlier when 513 flood days were tallied in 2015, he added.
The report only examined coastal flooding, not inundation brought on by sudden, heavy rain or overflowing rivers. As sea levels rise, it no longer takes a strong storm or hurricane to cause coastal flooding. It now occurs with high tides in many locations.
Also known as a nuisance or clear-sky flooding, the phenomenon has increased by as much as 1,000% in some areas since the 1960s. NOAA tracks high-tide floods in 28 coastal cities.