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This study explores soil moisture in Tibet using satellite data. Factors influencing moisture levels and applications in climate research are discussed. Data analysis methods and variance explanations are detailed. Regional models and validation techniques are presented for climatology and environmental monitoring.
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Soil moisture in Tibet derived from satellite obsevations C. Simmer and R. Lindau University of Bonn DFG Round Table – Frankfurt a.M. – 23th May 2006
Total variance External variance Internal variance = Variance between + Mean variance the means of the within the subsamples subsamples ANOVA of Soil Moisture measurements DFG Round Table – Frankfurt a.M. – 23th May 2006
Local longtime means 73% of the soil moisture variance is explained by four parameters : DFG Round Table – Frankfurt a.M. – 23th May 2006
Two-step Retrieval Climatological mean derived from: • Longterm precipitation • Soil texture • Vegetation density • Terrain slope + Temporal anomalies from: • Brightness temperatures at 10 GHz • Anomalies of rain and air temperature DFG Round Table – Frankfurt a.M. – 23th May 2006
Application: DEKLIM BALTIMOS within DEKLIM (Deutsches Klimaforschungsprogramm): Validation of a 10-years climate run of the regional model REMO using SMMR. Example: Oder catchment R. Lindau and C. Simmer: Derivation of a root zone soil moisture algorithm and its application to validate model data. Nordic Hydrology, accepted for publ. DFG Round Table – Frankfurt a.M. – 23th May 2006
Application: AMSR GEOLAND within GMES (Global Monitoring for Environment and Security): Derivation of global soil moisture fields from AMSR M. Leroy, R. Lacaze, R. Lindau, F. Oleson, L. Pessanha, I. Piccard, A. Rosema, J-L. Roujean, F. Rubel, W. Wagner, M. Weiss, 2004: Towards a European Service Center for Monitoring land surfaces at global and regional Scales: The GEOLAND/ CSP Project International Archives of Photogrammetry and Remote Sensing, XXth ISPRS Congress, Istanbul, 35 (B4), 783-790. Longterm mean Temporal anomaly DFG Round Table – Frankfurt a.M. – 23th May 2006
Mean Soil Moisture in Tibet • The longtime mean field is characterized by strong gradients Three points on the above section show decreasing soil moisture towards NW with a minimum in August DFG Round Table – Frankfurt a.M. – 23th May 2006
Annual Cycle Feb May Nov Aug DFG Round Table – Frankfurt a.M. – 23th May 2006