Algorithm development PI : Prof. Toshio Koike (University of Tokyo)
The main caveats are described below when you use the AMSR-E Level 2 standard products (Version 2.0) of soil moisture. (Version 2.0) of soil moisture.
Since Version 2.0 is the first release of AMSR-E, no Version 1.0 exists before this.
It covers whole global land surfaces with the exception of permanent land ice masses in Greenland and Antarctica, and dense forest area.
SM is estimated with an error of 0 to 0.6 g/cm3. Based on the AMSR-E data in Mongolia from Oct 2002 to Sep 2003 (except for winter season) and its 12 matched-up ground observation data, the standard error is considered to be 0.043 g/cm3. Further validation will be needed for the accuracy of global estimation.
Dense forest regions are masked out.
The estimation in the snow-covered area is not available. Masking for this region is currently under discussion.
Koike,T., Y. Nakamura, I. Kaihotsu, G. Davva, N. Matsuura, K. Tamagawa and H. Fujii, Development of an Advanced Microwave Scanning Radiometer (AMSR-E) Algorithm of Soil Moisture and Vegetation Water Content, Annual Journal of Hydraulic Engineering, JSCE, Vol. 48(2), pp217-222, 2004.