Human-Engineered Changes on Mississippi River Increased Extreme Floods
As the Mississippi River enters the Gulf of Mexico, it loses energy and dumps its load of sediment that it has carried on its journey through the middle of the North American continent. This pile of sediment, or mud, accumulates over the years building up the delta front. Captions and photo source: NASA
A new study has revealed for the first time the last 500-year flood history of the Mississippi River. It shows a dramatic rise in the size and frequency of extreme floods in the past century—mostly due to projects to straighten, channelize, and bound the river with artificial levees.
The new research, led by scientists at Woods Hole Oceanographic Institution (WHOI), also uncovered a clear pattern over the centuries linking flooding on the Mississippi with natural fluctuations of Pacific and Atlantic Ocean water temperatures. This newly recovered long-term record provides a historical context that spotlights how more recent river engineering has intensified flooding to unprecedented levels…