File(s) under permanent embargo
Comparison of Microwave Backscatter Anisotropy Parameterizations of the Antarctic Ice Sheet
conference contribution
posted on 2023-05-23, 17:39 authored by Alexander FraserAlexander Fraser, Neal YoungNeal Young, Adams, NDThe Antarctic Ice Sheet exhibits a strong anisotropy in microwave backscatter, both as a function of azimuth angle and incidence angle. This anisotropy arises as a result of i) the alignment of roughness elements and other wind-related surface and sub-surface features, as well as ii) internal layers and snow grain size gradient within the snowpack. As a result of its antenna configuration, the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) Advanced SCATterometer (ASCAT) satellite instrument is able to observe much of the continent with a large azimuth and incidence angle diversity. A lack of azimuth and incidence diversity has restricted previous backscatter parameterisations to relatively simple bi-sinusoidal (azimuth angle) and linear (incidence angle) parameterisations. Using ASCAT, we show that a better fit can be obtained using a cubic incidence angle function and a Fourier series of up to four terms for parameterisation of the azimuth angle anisotropy. Scatterometer instruments have previously been used in Greenland to retrieve accumulation rate by observing the change in backscatter as a function of incidence angle. Here we present preliminary results of an empirical study linking the isotropic component and incidence angle dependence to snow accumulation rate in Antarctica, using snow stake measurements as ground truthing.
Funding
University of Tasmania
History
Publication title
International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Volume XXXIX-B8, 2012Volume
XXXIX-B8Editors
M. Shortis, H. Shimoda, K. ChoPagination
573-577ISSN
2194-9034Department/School
Institute for Marine and Antarctic StudiesPublisher
International Archives of the Photogrammetry, Remote Sensing and Spatial Information SciencesPlace of publication
Melbourne, AustraliaEvent title
XXII ISPRS CongressEvent Venue
Melbourne, AustraliaDate of Event (Start Date)
2012-08-25Date of Event (End Date)
2012-09-01Repository Status
- Restricted