IMPACTS OF RELATIVE SEA-LEVEL RISE AND EXTREME STORMS ON COASTAL GEOMORPHIC CHANGE AND BARRIER ISLAND EVOLUTION IN LOUISIANA

摘要

The effects of historical and ongoing coastal change are complex. Detecting and measuring change in coastal environments is essential for effective scientific evaluation of historical coastal change and monitoring of future changes. Predicting change scenarios requires combining a number of different technological monitoring components (i.e., lidar-derived shoreline topography integrated with seafloor bathymetry) with historical data to develop a baseline barrier-shoreline evolution scenario. Relative sea-level rise and extreme storms are two of the primary driving forces impacting coastal Louisiana in two completely different ways. South-central Louisiana barriers islands are drowning in place due to rising sea level, limited sediment, and storm erosion. In contrast, the Chandeleur Islands have also been losing land historically and were greatly affected by Hurricane Katrina, but are starting the natural rebuilding post-storm process. These coastline responses were detected by monitoring and repetitive surveys using multiple data components.