Aqua/AMSR-E L2 AMSR2 Format Soil Moisture Content

It conically scans and keeps an angle of incidence on the earth surface (a nominal of 55 degrees) and accomplishes a swath width of about 1450 km. The AMSR-E reached its limit to maintain the antenna rotation speed necessary for regular observations, and the AMSR-E restarted its observation in slow rotation mode (2 rotations per minute) on December 4, 2012. However, the AMSR-E reached its limit to maintain the antenna rotation speed necessary for slow rotation mode and it automatically halted its observation and rotation on December 4, 2015.

Level 2 product stores the Geophysical quantity from the brightness temperature of level 1 product. This product includes Soil Moisture Content (SMC). In general, at a smooth interface between two semi-infinite media, the emissivity is equal to one minus the Fresnel power reflectivity, which is calculated by using dielectric constant of the media and incident angle.

Among the water surface emissivity at AMSR observing frequencies, 6.9; l0.6, 18.7, 36.5 and 89 GHz, the emissivity is larger at the higher frequency than at the lower one for both polarizations. The index, the discrepancy between the brightness temperatures at two frequencies divided by one at lower frequency, can be used as an index for surface wetness. The physical quantity unit is %.

Also, the quality flag for each observation point (Pixel Data Quality) is stored. The provided format is HDF5. Spatial resolution is 10 km.

The current version of the product is "Version 8". The generation unit is scene (defined as a half orbit).