The Study Of Height Change In Antarctic Ice Sheet By Using Icesat Laser Altimeter Data

The melting of polar ice sheet is one of the main dynamic factors which affect the global climate change, and contribute to global sea-level rise. Satellite altimetry, specially satellite laser altimetry, has provided useful information about the height and height change of polar ice sheet. ICESAT (Ice, Cloud, and Land Elevation Satellite) satellite, as part of NASA's (National Aeronautics and Space Administration) EOS (Earth Observing System), was launched on January 13, 2003 from California's Vandenberg Air Force Base. The main scientific purpose of ICESAT is to measure ice sheet topography and its time varying.The methods for obtaining height of polar ice sheet height and height change using ICESAT laser altimetry data is presented in this paper. The main works are followed as:1. Basic principles and applications of the ICESAT laser altimeter are introduced, and the algorithm of laser ranging and footpoint location determination is given.2. Algorithms of the waveform processing is introduced, the land cover classification and parameters determination of surface characters using ICESAT waveform are also analyzed.3. Corrections for tides, atmospheric delay correction to ICESAT altimetry data are analyzed.4. The height of Antarctic ice sheet from ICESAT altimeter data is compared with the GPS data, the accuracy of ICESAT data is estimated.5. DEM of the Antarctic ice sheet is derived by using ICESAT laser altimeter data, and elevation changes are analyzed by comparing DEM in different periods.