Global passive microwave radiometer data from the AMSR-E instrument, measuring vertically and horizontally polarized brightness temperatures at six frequencies from 6.925 to 89.0 GHz. The instrument was developed by AMD_KOPRI and data collection occurred throughout 2005. Measurements have spatial resolutions ranging from 5.4 km to 56 km depending on the frequency channel.
Use Cases
- Derive sea ice concentration and extent by analyzing polarization differences in the 6.925 GHz and 36.5 GHz brightness temperature channels.
- Estimate global soil moisture levels using the sensitivity of the 10.65 GHz channel to surface wetness.
- Retrieve atmospheric water vapor and cloud liquid water content by exploiting the atmospheric absorption features at the 23.8 GHz frequency.
- Monitor rainfall rates over oceans by detecting emission and scattering signatures across the 18.7 GHz and higher frequency channels.
- Study snow water equivalent by modeling the scattering signal from snowpack using the 36.5 GHz and 89.0 GHz measurements.
Strengths
- Provides 12 distinct measurement channels across 6 microwave frequencies (6.925, 10.65, 18.7, 23.8, 36.5, 89.0 GHz).
- Offers dual-polarization (vertical and horizontal) measurements for all channels, enabling analysis of surface scattering properties.
- Global coverage with a constant Earth incidence angle of 55 degrees and a swath width enabling frequent revisits.
Limitations
- Spatial resolution is coarse, varying from 56 km at 6.9 GHz to 5.4 km at 89.0 GHz, limiting fine-scale analysis.
- Data is from a single year (2005), providing a snapshot rather than a long-term climate record.
- Brightness temperatures are level-1 data; deriving geophysical variables requires additional processing and validation.
Provenance
- Source
- NASA Earthdata platform, provided by organization AMD_KOPRI.
- Collection Method
- Collected by the AMSR-E instrument's offset parabolic reflector scanning the Earth, with calibration using cosmic background radiation and an on-board warm target.
- Time Range
- 2005
- Freshness
- null
- Geography
- Global