High-tide flooding in Washington on March 27. (Angela Pan/Flickr)
High-tide flooding, which can wash water over roads and inundate homes and businesses, is an event that happens once in a great while in coastal areas. But its frequency has rapidly increased in recent years because of sea-level rise. Not just during storms but increasingly on sunny days, too.
Years ago, the late Margaret Davidson, a coastal programs director at the National Oceanic and Atmospheric Administration, warned it wouldn’t be long until such flooding became routine. “Today’s flood will become tomorrow’s high tide,” she said.
A new NOAA report has published startling new projections that affirm Davidson’s warning.
By 2100, the report says, “high tide flooding will occur ‘every other day’ (182 days/year) or more often” even under an “intermediate low scenario” in coastal areas along the East Coast and Gulf of Mexico. This scenario works under the assumption that greenhouse gas emissions — which warm the climate and speed up sea-level rise — are curbed.
For a more aggressive “intermediate” scenario, in which greenhouse gas emissions carry on at today’s pace, high-tide flooding is forecast to occur 365 days per year.