SEA ICE AND ICE SHEET SURFACE ROUGHNESS CHARACTERIZATION AND ITS EFFECTS ON BI-DIRECTIONAL REFLECTANCE

Abstract

The roughness of sea ice can affect its bidirectional reflectance distribution function (BRDF) thus influencing retrieval of its physical properties from satellite. We leverage WorldView-1 and Multi-angle Imaging SpectroRadiometer (MISR) remote sensing data sets collected over sea ice and the adjacent McMurdo Ice Shelf in proximity to McMurdo station to first characterize the roughness of sea ice and other snow surfaces and then examine the effects of surface roughness on satellites images of varying spatial resolutions. First, high resolution DEMs were created from stereographic WorldView-1 image pairs with NASA stereo imagery processing tool Ames Stereo Pipeline (ASP). A variety of geomorphometric measures of roughness, including roughness index, were characterized from the high resolution DEMs. Following adequate characterization of sea ice roughness, its impact on surface reflectance derived from optical satellites spanning a range of spatial resolutions was assessed.