Monthly Land Ice Surface Snow Diagnostics from NASA Reanalysis

MERRA-2 M2TMNXGLC provides monthly mean assimilated land ice surface diagnostics on a 0.625 x 0.5 degree global grid. NASA's Global Modeling and Assimilation Office (GMAO) produces this data using the GEOS model, covering the period from 1980 to the present with approximately three weeks latency.

Use Cases

• Model snow mass residual due to densification over glaciated surfaces using the total snow mass residual field.
• Analyze fractional snow cover trends on land ice by region using the fractional area of glaciated surface snow cover variable.
• Estimate snow depth and water equivalent on ice sheets using the snow depth over glaciated surface and snow mass over glaciated surface parameters.
• Study variance in surface conditions on land ice using the included variance parameters for certain diagnostics.

Strengths

• Continuous temporal coverage from 1980 to present enables long-term trend analysis.
• Data is produced by NASA's GMAO using a consistent assimilation model (GEOS 5.12.4).
• Provides a global spatial grid at 0.625 x 0.5 degree resolution for land ice surfaces.

Limitations

• Data is a reanalysis product, representing model estimates constrained by observations, not direct measurements.
• Latency of approximately three weeks after month-end limits near-real-time applications.
• Specific row counts and file sizes for the collection are not provided.

Provenance

Source

NASA Global Modeling and Assimilation Office (GMAO) via the GES DISC.

Collection Method

Assimilated reanalysis from the Goddard Earth Observing System Model (GEOS) version 5.12.4.

Time Range

1980 to present

Freshness

Updated monthly with ~3 week latency.

Geography

Global land ice surfaces on a 0.625 x 0.5 degree grid.