Exploring the Coastal Dynamic Response Along the Southeastern US Coast and Morocco
Abstract
Globally, coastal regions are extremely vulnerable to the effects of sea level rise and coastal subsidence. Using InSAR, UAVs, and LiDAR, this study evaluated the coastal responses in both the southeastern (SE) United States and Agadir, Morocco located in the coastal northwest region of Africa. This study outlines the climatic impacts and changes on the hydrogeology and geomorphology both spatially and temporarily. Geologically, both regions are composed of unconsolidated sedimentary material and have similar climate conditions (e.g., humid-subtropical climate, droughts, floods, interannual and interdecadal precipitation variability, and evaporation rates related to sea-surface temperature anomalies). Each region was evaluated to understand how the geomorphologic and anthropogenic changes effected the coastal dynamic response to sea level rise and groundwater withdrawal impacts. SE US displays volumetric change of 0-0.03 % net gain/ 0-0.05 % net loss of sediment dependent upon erosional events. The Plio-Quaternary Plain Aquifer of Agadir pumps 650 MCM/yr from over 20,000 wells, exceeding the recharge rate by 260 MCM/yr. These practices put the aquifer in extreme risk of groundwater table drawdown (0.5 m-2.5 m/yr). InSAR data from over 400 scenes acquired from a CAT-1 proposal from the European Space Agency were used to determine coastal subsidence due to overexploitation of groundwater withdrawal by: (1) identifying the rate of coastal subsidence using radar interferometry and (2) converting relative change to absolute change to understand the spatial distribution and temporal changes of the coastal area. The UAVs in conjunction with a differential GPS system were used to identify high-resolution temporal elevation changes, acquire GPS data, and obtain high-resolution measurements. The high-resolution static and repeated measurements examine changes in each region synthesizing the hydrological response due to changes in geomorphology. InSAR data was processed in ENVI SARSCAPE using two-pass interferometry and interferometric stacking techniques, UAV data was processed in Agisoft and LiDAR derived DEMs at 1m scale resolution acquired from NOAA were processed in ENVI and ArcGIS. These results can improve coastal water resources and the understanding of the coastal geomorphologic dynamic.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFMEP11E2113R
- Keywords:
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- 3020 Littoral processes;
- MARINE GEOLOGY AND GEOPHYSICS;
- 4315 Monitoring;
- forecasting;
- prediction;
- NATURAL HAZARDS;
- 4316 Physical modeling;
- NATURAL HAZARDS;
- 4217 Coastal processes;
- OCEANOGRAPHY: GENERAL