This week, New Orleans welcomes 25,000 earth, environmental and geological scientists from around the world for the American Geophysical Union conference — the largest annual gathering of natural scientists. These scientists will enjoy our state’s culture and hospitality, but their arrival also presents an opportunity to showcase one of the planet’s most pressing scientific challenges: how to restore and adapt Louisiana’s coastline to protect its residents and businesses from flooding in the face of climate change. We call upon these scholars to learn the startling facts about our coast and bring their expertise to bear on this complex, globally-significant problem.
Louisiana has lost nearly 2,000 square miles of land over the past century due to construction of levees along the Mississippi River that prevent sediments and freshwater from reaching wetlands, man-made canals, hurricanes, resource extraction, subsidence, oil spills and global sea-level rise. In the years ahead, the effects of climate change, particularly sea-level rise, will bring future losses to this ecological, geological, social, economic and political landscape.
The acceleration in global sea-level rise rates, occurring along a coastline with one of the world’s highest rates of subsidence, challenges the sustainability of wetlands that provide protection for the nation’s largest commercial waterways, billions of dollars in energy-related infrastructure, and coastal communities like New Orleans. Scientists estimate that over the next 50 years, Louisiana could lose another 2,250 to 4,125 square miles of land. This crisis is such an existential threat, that earlier this year, Gov. John Bel Edwards declared a state of emergency.
But Louisiana has a science-based, publicly-informed plan to restore the coast and protect it against storm surge — and this is an area where the global scientific community can contribute to, and learn from, Louisiana.
Using predictive models, the 50-year, $50-billion Coastal Master Plan recognizes the stark realities that land loss and sea-level rise could have on reducing coastal sustainability and increasing flood risk. The plan builds land by reconnecting the Mississippi River to its delta via diversions and by dredging sediments from the river’s bottom and placing them where needed. It also provides flood protection by building stronger levees and encouraging homeowners to flood proof, elevate, and in some instances, relocate their homes. The Louisiana Legislature unanimously passed this plan in 2012 and 2017, and the state now has about $7 billion from the Deepwater Horizon oil spill settlements to start putting it into action.
Louisiana is not alone. Much of the world’s population lives near the coast, and the challenges Louisiana faces are similar to those being faced in Tokyo, New York, Houston and Bangladesh. Sea level rise is a global problem, and scientists have much to gain by studying Louisiana.
ALEXANDER S. KOLKER
professor, Louisiana Universities Marine Consortium and Department of Earth and Environmental Science, Tulane University
science policy director, Mississippi River Delta Restoration, Environmental Defense Fund