Lake Qinghai: Chinese site for radiometric calibration of satellite infrared remote sensors

Abstract

Abstract Lake Qinghai is the most important of the Chinese radiometric calibration sites (CRCSs) for on-orbit radiometric calibration of satellite infrared (IR) channels. This letter introduces the site and describes annual CRCS field experiments, the buoy measurement facilities and surface temperature spatial distribution analysis based on Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the Terra (EOS AM) satellite and buoy data for Lake Qinghai. The lake located at a high altitude (3196 m) has clean water, a stable geological substrate and a dry and clear atmosphere, with few aerosol particulates. The spatial distribution of the water surface temperature is very uniform. For these reasons, Lake Qinghai is a good thermal IR target for the radiometric calibration of Earth observation remote sensors and is used not only for Chinese satellites but also for on-orbit radiometric calibration of many Earth observation satellites. Acknowledgements This work is supported by National Natural Science Foundation of China (grant no. 41171275, no. 40905014 and no. 40701118) and the R&D Special Fund for Public Welfare Industry (grant no. GYHY200906036). We thank Lei Yang from China Center for Resources Satellite Data and Application for providing HJ-1B data.