Submitted to: American Geophysical Union
Publication Type: Abstract Only
Publication Acceptance Date: December 15, 2006
Publication Date: May 23, 2008
Citation: Lang, M.W., Townsend, P., Kasischke, E. 2008. Influence of incidence angle on the use of C-band SAR data for the detection flooded forests [abstract]. American Geophysical Union. 87(52).
Hydrology is the single most important factor in the formation and functioning of a wetland. Many limitations still exist to accurately characterize wetland hydrology over large spatial extents, especially in forested wetlands. Imaging radar has emerged as a viable tool for forested wetland flood mapping, although the limitations of radar data have not been fully explored. The influence of incidence angle on the ability to detect flooding in different forest types was examined along the Roanoke River in North Carolina using Radarsat (C- HH) data collected during the leaf-off and leaf-on seasons. Backscatter generally decreased with increasing incidence angle under all conditions, but the distinction between flooded and non-flooded areas did not decline sharply with incidence angle as predicted. The ability to detect flooding under leaf-on conditions varied much more according to incidence angle while forest type had a greater effect during the leaf-off season. Differentiation of flooded and non-flooded forests was similar during the leaf-off and leaf-on seasons. Use of a wider range of incidence angles during the entire year increases the temporal resolution of imagery which may, in turn, enhance mapping of inundation beneath forest canopies.