This data set contains daily, gridded snow cover and albedo derived from radiance data acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) on board the Aqua satellite. Snow cover is identified using the Normalized Difference Snow Index (NDSI) and a series of screens designed to alleviate errors and flag uncertain snow cover detections.
NOTE: Reverb will be decommissioned in the coming months and replaced with Earthdata Search. All links to Reverb will be removed at that time.
MODIS/Aqua Snow Cover Daily L3 Global 500m Grid, Version 6
Changes for Version 6 include:
- Fractional Snow Cover has been replaced by Normalized Difference Snow Index (NDSI) snow cover. Fractional Snow Cover is no longer calculated;
- The binary Snow-Covered Area (SCA) map has been discontinued;
- Aqua MODIS band 6 data have been restored to scientific quality using a Quantitative Image Restoration (QIR) technique. Aqua now uses the same snow detection algorithm as Terra;
- Existing data screens designed to reduce snow detection errors have been revised and several new screens have been added;
- Data screen results, including snow detection reversals and detections with increased uncertainty, are provided in a new QA bit flag;
- Basic pixel-level QA uses new criteria to indicate the overall quality of algorithm result;
- Pointers are provided to locate the swaths used for each day's observation.