Surface characterization analysis of inner mongolia plateau area (China) as potential satellite calibration sites, using MODIS(Terra and Aqua) instrument

A good calibration of satellite is necessary to derive reliable quantitative measurements of the surface parameters or to compare data obtain from different sensors. DCSRS (Demonstration Center for Spaceborne Remote Sensing of China National Space Administration) went to inner-Mongolia Plateau to seek fairly uniform reflectance sites as a part of Beijing multifunctional test site network in May and October 2006, and four quite flat and homogenous sites were selected as potential test sites. These four sites have many good calibration site characteristics: they are large and flat; the rain is little and the evaporation is much larger than precipitation, so the water vapor content is little in atmosphere; the elevation is about 1100 m and the weather is sunny in most time. In this study, more than 200 MODIS level 1 images of these four sites were obtained and the average reflectance and relative mean squared deviation of each image were calculated. In the end, the variation of reflectance with solar zenith, month and season were analyzed, and the result was consistent with in-situ investigation.