Average radar intensity over the Great Dismal Swamp Refuge (GDSR) in North Carolina and Virginia has a close relationship with changing groundwater levels. Using PALSAR and RADARSAT2 Interferometric Synthetic Aperture Radar (InSAR) observations, the FWS estimated surface water level changes over the GDSR with repeat satellite radar imagery. This state-of-the-art research was done by Dr. Jinwoo Kim and Dr. Zhong Lu at Southern Methodist University with funding support by the U.S. Geological Survey and local logistical support by the FWS.
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Great Dismal Swamp Refuge PALSAR images during the dry and wet seasons. This graphic illustrates how the image is tied to the changing water levels shown in the chart.