Publications

A comparison of land surface temperature (T_s) derived from the Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E) with infrared T_s is presented. The infrared T_s include clear-sky estimates from the Moderate Resolution Imaging Spectroradiometer (MODIS), the Spinning Enhanced Visible and Infrared Imager, the Geostationary Operational Environmental Satellite (GOES) Imager, and the Japanese Meteorological Imager. The higher discrepancies between AMSR-E and MODIS are observed over deserts and snow-covered areas. The former seems to be associated with T_s underestimation by MODIS, whereas the latter is mostly related to uncertainties in microwave emissivity over snow/ice. T_s differences between AMSR-E and MODIS are significantly reduced after masking out snow and deserts, with a bias change from 2.6/4.6 K to 3.0/1.4 K for day time/night time and a standard deviation(STD) decrease from 7.3/7.9 K to 5.1/3.9 K. When comparing with all infrared sensors, the STD of the differences between microwave and infrared T_s is generally higher than between IR retrievals. However, the biases between microwave and infrared T_s are, in some cases, of the same order as the ones observed between infrared products. This is the case for GOES, with daytime biases with respect to AMSR-E and MODIS of 0.45 K and 0.60 K, respectively. While the infrared T_s are clear-sky estimates, AMSR-E also provides T_s under cloudy conditions. For frequently cloudy regions, this results in a large increase of available T_s estimates (>250%), making the microwave T_s a very powerful complement of the infrared estimates.