High Tide Flooding
Annual occurrences of tidal flooding—exceeding local thresholds for minor impacts to infrastructure—have increased 5- to 10-fold since the 1960s in several U.S. coastal cities. The changes in high tide flooding over time are greatest where elevation is lower, local RSL rise is higher, or extreme variability is less.
In a sense, today’s flood will become tomorrow’s high tide, as sea level rise will cause flooding to occur more frequently and last for longer durations of time.
The red layer in the map represents areas currently subject to tidal flooding, often called “recurrent or nuisance flooding.”