DFG Round Table – Frankfurt a.M. – 23th May 2006

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

ANOVA of Soil Moisture measurements

Variance in mm2 Number of bins

Error of the total

mean

Seeming external variance

Error of external means

Internal variance

True external variance

Relative external variance

Annual Cycle 36 2 388 51 10343 338 3.16%

Interstation 48 2 9133 10 1558 9123 85.40%

Interannual 8 2 39 12 10654 26 0.25%

Total variance External variance Internal variance

= Variance between + Mean variance

the means of the within the subsamples subsamples

DFG Round Table – Frankfurt a.M. – 23th May 2006

Local longtime means

single cumulative

Climatolog. rain 58.6 58.6

Soil texture 0.5 69.0

Vegetation 37.7 72.8

Terrain slope 2.8 73.0

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.

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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 NWwith a minimum in August

DFG Round Table – Frankfurt a.M. – 23th May 2006

Annual Cycle

Feb

Aug

May

Nov