Friday, July 3rd, 2009

The Disappearing Mississippi Delta

Mississippi Delta image acquired on May 24, 2001 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team

Rising sea levels and not enough sediment replenishment may make much of the Mississippi Delta 'drown' by the year 2100, according to a new study. Writing this week in the journal Nature, researchers examined rates of sediment deposition in the Mississippi delta over the past 12,000 years. Once upon a time, plenty of sediment flowed downstream to form the Delta -- but now, due to dams and levees, substantially less sediment ends up in the Delta region. The authors estimate that between 18 and 24 billion tons of sediment would be required by the year 2100 to sustain the existing surface area of the Mississippi delta as sea levels rise -- more sediment than exists within the entire Mississippi. We'll find out more.

Guests

Ivor van Heerden
Author, "The Storm: What Went Wrong and Why During Hurricane Katrina--the Inside Story from One Louisiana Scientist"
Director, LSU Hurricane Public Health Center
Louisiana State University
Baton Rouge, Louisiana