ASSESSMENT OF NEAR-NADIR CORRELATION CHARACTERISTICS OVER WATER BODIES USING INTERFEROMETRIC SAR: IMPLICATIONS FOR THE SWOT MISSION

This paper introduces the use of an airborne interferometric synthetic aperture radar (InSAR) to estimate water surface decorrelation times at Ka-Band. Such an assessment is directly relevant to the upcoming Surface Water and Ocean Topography mission, especially for surface water bodies such as lakes and rivers since the surface decorrelation may limit the spatial resolution achievable by the mission to delineate water spatial boundaries. Initial assessments indicate decorrelation times consistent with limited published observations for the ocean and fresh water bodies (several milliseconds). However, there are challenges both in terms of the phenomenology and in the instrument sensitivity to longer decorrelations.