HR: 1330h
AN: G23A-02    [Abstracts]
TI: C-band Radar Observes Water-level Change in Coastal Louisiana Swamp Forests
AU: * Lu, Z
EM: lu@usgs.gov
AF: USGS National Center, EROS, 47914 252nd Street, Sioux Falls, SD 57198 United States
AU: Crane, M
EM: mpcrane@usgs.gov
AF: USGS National Center, EROS, 47914 252nd Street, Sioux Falls, SD 57198 United States
AU: Kwoun, O
EM: okwoun@usgs.gov
AF: USGS National Center, EROS, 47914 252nd Street, Sioux Falls, SD 57198 United States
AU: Wells, C
EM: cwells@usgs.gov
AF: USGS, National Wetlands Research Center, Lafayette, LA 70506 United States
AU: Swarzenski, C
EM: cswarzenski@usgs.gov
AF: USGS, Water Resources District Offfice, Baton Rouge, LA 70816 United States
AU: Rykhus, R
EM: rykhus@usgs.gov
AF: USGS National Center, EROS, 47914 252nd Street, Sioux Falls, SD 57198 United States
AB: It is commonly recognized that C-band (wavelength of 5.7 cm) radar pulses backscatter from the upper canopy of swamp forests. Consequently, interferometric analysis of C-band imagery has not been exploited to study water-level changes in swamp forests. Using C-band ERS-1 and ERS-2 radar images, we showed that interferometric synthetic aperture radar (InSAR) images maintained adequate coherence over swamp forests composed of moderately dense trees with a medium-low canopy closure in southeastern Louisiana over a time window of a few months. This unexpected phenomenon is believed to be due to double-bounce returns of C-band radar signal reflecting off tree trunks and the water surface. The persistent coherence of C-band radar signal over swamp forests allowed us to measure changes in water-level beneath tree cover with an unprecedented degree of vertical accuracy. Future InSAR images with shorter repeat times will be capable of characterizing the temporal evolution of water-level changes to improve hydrological modeling predictions and enhance assessments of future flood hazards over wetlands.
DE: 1243 Space geodetic surveys
DE: 1890 Wetlands
DE: 1894 Instruments and techniques
DE: 1899 General or miscellaneous
SC: Geodesy [G]
MN: 2005 Joint Assembly