Snowpack properties in Dronning Maud Land, Antarctica, compared to Envisat ASAR and scatterometer measurements
The knowledge of snow pack properties and its temporal and spatialvariability is of importance for the interpretation of backscatteredsignals in the microwave region. For example, forthcoming radaraltimetric satellite missions, like ESA's CRYOSAT, aim at improvedmeasurements of both ice surface height and surface height fluctuation,which is especially needed at the margins of the continental ice sheetswhere the topography is more complex.This investigation focuses on the area between the German Neumayer base(70°39'S, 08°15'W) at the ice shelf Ekströmisen and the drilling sitefor the EPICA (European Project on Ice Coring in Antarctica) ice core atKohnen station (75°S, 0°W, 2850m a.s.l.) in Dronning Maud Land. ERSwindscatterometer data are used to retrieve the incidence angledependence and azimuthal anisotropy of backscattering of various snowpack types. These parameters are used to normalize Envisat ASAR(Advanced Synthetic Aperture Radar) wide swath data, which were acquiredin 2004 using the same polarization. Envisat data are compared to snowaccumulation, derived by stake readings and firn core drilling, and snowpack properties, derived from snow pit measurements. Finally,backscattering data in C-VV are compared to C-HH (Envisat, Radarsat) andKu-VV and Ku-HH (NSCAT).The analysis demonstrates that coarse resolution scatterometer data andhigh resolution SAR data can be usefully merged over the flat terrain ofthe Antarctic inland in order to improve the classification of varioussnowpack types.
Helmholtz Research Programs > MARCOPOLI (2004-2008) > POL1-Processes and interactions in the polar climate system