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Z. Bartalis:
"Monitoring Seasonal Standing Water over Central Siberia Using Ku-Band Scatterometer Data";
Betreuer/in(nen): W. Wagner, B. Graneli, R. Kidd, K. Scipal; Institut für Photogrammetrie und Fernerkundung, 2004.

The thesis tries to answer the following question: "Can Ku-band scatterometry data be used to identify location, duration and extent of seasonal standing water in Central Siberia?". The temporal/spatial distribution of seasonal standing water is determined by the freeze-thaw cycles, wetland distribution, soil moisture conditions and annual flooding patterns and is in turn essential for estimating carbon fluxes (methane, carbon dioxide) and for climate change studies.

Central Siberia was chosen as study region since it is one of the largest, most important and least monitored biomes in the world, with large implications for global climate change. In addition, the Institute of Photogrammetry and Remote Sensing at the Vienna Technical University (I.P.F.) participates in the on-going SIBERIA-II project from which extensive reference data can be drawn. A future integration of the results into SIBERIA-II appears realistic.

The choice of Ku-band is justified by the readily available data from the SeaWinds instrument onboard NASA´s QuikScat satellite. The spatial resolution of the data is coarse (about 30 km) but the temporal sampling rate is excellent (enough measurements per day even for studies of diurnal effects). This data was originally intended for sea backscatter applications (wind measurements) but has shown to be useful even for land applications.

Most importantly, work by Son Nghiem from NASA JPL has suggested the capability of the SeaWinds for mapping flooded areas. It has been concluded that the potential of polarimetric studies of standing water depends significantly on the extent of water areas inside the satellite footprint, both topsoil moisture and water surfaces having important contributions to the co-polarization ratio. The study of the extent of standing water is complicated by the polarimetric effects observed during snowmelt.

http://publik.tuwien.ac.at/files/PubDat_119761.pdf