The Mississippi River Delta Gulf Coast of the state of Louisiana faces huge problems stemming from the loss of land due to sea level rise, coastal erosion, and subsidence. In 2011, the U.S. Geological Survey reported that Louisiana loses a piece of land the size of a football field every hour (Couvillion et al., 2011)—an axiom that has become a rallying cry for coastal communities and scientists confronting these problems. This primer explores the causes of coastal land loss in Louisiana and it examines how human populations have dealt with these problems in the past, as well as what we can do about them today.
The first part of this primer deals with how the land surfaces of the Mississippi River Delta Gulf Coast formed in the past and the reasons why they are disappearing today. It briefly outlines the role of Mississippi River in depositing sediment and building up land surfaces. Next, it discusses three major natural forces that are responsible for the loss of land surfaces and sediments today: (1) the rise of global sea levels due to global warming and melting glacial ice; (2) the erosion land surfaces resulting from tropical storms, storm surges, and other high-energy surf events; and (3) geological subsidence, which is the sinking of land surfaces under the weight of the sediments deposited by the Mississippi River.
The second part of this primer examines how past human populations have coped with sedimentation from the Mississippi River and shifting coastlines. It looks at how the first Native American inhabitants of the Mississippi River Delta Gulf Coast responded to geological and environmental changes in the past. It also looks at how European colonial populations adapted to problems posed by both the Mississippi River and the Gulf of Mexico in organizing their cities, towns, ports, and farms. Finally, the second part of this primer explores the ways in which past human actions have contributed to the problems related to coastal land loss today.
The last part of this primer looks at the options facing coastal populations in Louisiana today. On the one hand, it examines the human activities that have been responsible for coastal land loss along the Mississippi River Delta Gulf Coast. On the other hand, it outlines the various plans that have been proposed to cope with the causes of land loss in the future.