Historical MODIS/Terra Snow Cover, Albedo, and Physical Properties

Historical daily data provides a spatially and temporally complete (STC) record of snow properties derived from MODIS/Terra surface reflectance. The dataset includes snow fraction, albedo (clean and observed), radiative forcing, darkening, and grain size, with processing that improves cloud identification and corrects for satellite view angle. It is produced and distributed by the NSIDC DAAC as an enhanced version of the MODSCAG and MODDRFS products.

Use Cases

• Modeling snowmelt runoff and water supply forecasts based on daily snow cover fraction and albedo.
• Studying climate feedbacks by analyzing trends in clean snow albedo and snow darkening from impurities.
• Assessing radiative forcing impacts on regional climate using the snow radiative forcing parameter.
• Validating snow models with spatially complete, daily estimates of snow grain size and on-the-ground snow cover.

Strengths

• Spatially and temporally complete (STC) processing fills gaps present in the source MODSCAG/MODDRFS products.
• Algorithm improves cloud identification and corrects for off-nadir viewing geometry, likely reducing commission/omission errors.
• Provides derived parameters not in the original products, such as snow albedo for both flat and sloped surfaces.

Limitations

• Key metadata like row count, file size, and specific column names are unavailable across all sources.
• Conflicting 'last updated' dates (2026-04-10 on datagov vs. 2023-09-30 on nasa_earthdata) create uncertainty about data freshness.
• License is vaguely specified as 'other-license-specified', requiring further investigation for reuse.

Provenance

Source

NASA Jet Propulsion Laboratory (JPL), now produced and distributed by NSIDC DAAC as MODSCGDRF_NRT.

Collection Method

Derived from NASA historical MODIS/Terra surface reflectance data (MOD09GA v006 before 2021-12-28, MOD09GA v061 onwards) using the STC algorithm.

Time Range

Historical record from the MODIS/Terra mission; specific start date not provided.

Freshness

2026-04-10 02:10:43.572138 (from datagov, but conflicts with nasa_earthdata date)

Geography

Global, at 500m resolution in a sinusoidal (SIN) grid.