School of Geographic Sciences;
Nanjing University of Information Science&Technology;
Nanjing 210044;
National Meteorological Information Center;
China Meteorological Administration;
Beijing 100081;
Laboratory for Climate Studies;
National Climate Center;
China Meteorological Administration;
Beijing 100081;
snow; cover; assimilation; FY-3; satellite-based; snow; products; snow; cover; fraction;