100-year floods could occur yearly by end of 21st century
WASHINGTON — Most coastal communities will encounter 100-year floods annually by the end of the century, even under a moderate scenario where carbon dioxide emissions peak by 2040, a new study finds. And as early as 2050, regions worldwide could experience 100-year floods every nine to fifteen years on average.
A 100-year flood is an extreme water level that has a 1% chance of being exceeded in any given year and is based on historical data. Despite the name, 100-year floods can strike the same area multiple years in a row or not at all within a century. But a new study finds that those historical trends will no ...










