Derivation of hydrological parameters from ENVISAT ASAR wide swath data

Spatially distributed information about the current state of the land surface can be obtained from remote sensing measurements. These may be used with great benefit for the understanding of hydrological processes on the landscape level, where in situ measurements must fail due to lacking spatial coverage. The potential to quantify soil moisture conditions of the top soil layer, as well as the derivation of snow parameters by means of active microwave imagery has been successfully demonstrated in numerous studies. In contrast to earlier and rather experimental research efforts, data acquired from the ENVISAT ASAR sensor firstly enables to continuously monitor large areas with high temporal frequency and high spatial resolution. The different operation modes of ASAR allow the derivation of soil moisture maps on both, the field and the regional scale. The paper presents new methods to derive soil moisture and snow covered area information from ASAR wide swath (WSM) datasets. The presented approaches allocate a robust, yet practicable and reliable technique to derive near-surface soil moisture and snow patterns, being the key prerequisite for an operational application in hydrologic modelling.

[1]  E. T. Engman.  Microwave remote sensing of soil moisture, progress, potential and problems , 1995, 1995 International Geoscience and Remote Sensing Symposium, IGARSS '95. Quantitative Remote Sensing for Science and Applications.

[2]  N. Baghdadi.  Capability of multitemporal ERS-1 SAR data for wet-snow mapping , 1997 .

[3]  Wolfram Mauser,et al.  Generation of geometrically and radiometrically terrain corrected ScanSAR images , 2003, IGARSS 2003. 2003 IEEE International Geoscience and Remote Sensing Symposium. Proceedings (IEEE Cat. No.03CH37477).

[4]  Helmut Rott,et al.  Retrieval of wet snow by means of multitemporal SAR data , 2000, IEEE Trans. Geosci. Remote. Sens..

[5]  M. Rombach,et al.  Multi-annual analysis of ERS surface soil moisture measurements of different land uses , 1997 .

[6]  Heike Bach,et al.  Near-real-time derivation of snow cover maps for hydrological modeling using operational remote sensing data , 2003, IGARSS 2003. 2003 IEEE International Geoscience and Remote Sensing Symposium. Proceedings (IEEE Cat. No.03CH37477).

[7]  Pascale C. Dubois,et al.  Measuring soil moisture with imaging radars , 1995, IEEE Trans. Geosci. Remote. Sens..

[8]  Ralf Ludwig,et al.  Mesoscale soil moisture estimation from SAR data using subscale landuse information , 2003, IGARSS 2003. 2003 IEEE International Geoscience and Remote Sensing Symposium. Proceedings (IEEE Cat. No.03CH37477).

[9]  Jean-Pierre Wigneron,et al.  Estimation of Watershed Soil Moisture Index from ERS/SAR Data , 2000 .