Snow depth estimation over north‐western Indian Himalaya using AMSR‐E

Abstract

This paper presents the estimation of snow depth over north‐western Indian Himalaya using the 18.7H and 36.5H GHz channels of Advanced Microwave Scanning Radiometer‐EOS (AMSR‐E). The Microwave Emission Model of Layered Snowpacks (MEMLS) was used along with AMSR‐E to understand the difference in the snow pack emitted and sensor received signals due to the prevailing topography. The study shows that the brightness temperature of AMSR‐E and MEMLS are comparable at 18.7 GHz with some differences in their values at 36.5 GHz showing the sensitivity of this channel to the prevailing topography.

Three years of AMSR‐E data were used to modify the 1.59 algorithm to suit the terrain and snow conditions of the north‐western Indian Himalayas. The retrieved snow depth is then compared with ground observations. Data from December to February 2003–2006 were used for the study of snow depths less than 1 m. The modified algorithm estimates the snow depth better than the old algorithm over the mountainous terrains of the north‐western Himalayas.

Acknowledgements

The authors acknowledge Dr C. Matzler, University of Bern, Switzerland, for kindly providing us with the MEMLS model and for providing help with understanding the model. Thanks are also due to Dr R. Kelly of Waterloo University, Canada, Dr M. Tedesco of GSFC, NASA and Mr N. K. Thakur, SASE, for the helpful discussions and suggestions.