MODIS/Terra Snow Cover Daily L3 Global 500m Grid (MOD10A1) contains snow cover and quality assurance (QA) data in HDF-EOS format along with corresponding metadata. Data files after 14 September 2003 include a snow albedo array with a beta status. MOD10A1 consists of 1200 km by 1200 km tiles of 500 m resolution data gridded in a sinusoidal map projection. MODIS snow cover data are based on a snow mapping algorithm that employs a Normalized Difference Snow Index (NDSI) and other criteria tests. The only data available for Version 3 (V003) is the Golden Month, which is a sample of V003 data covering the time period 29 August 2002 (day of year 241) through 7 October 2002 (day of year 280). The Golden Month is only available by special request by contacting NSIDC User Services.