Monthly Land Surface Diagnostics from NASA MERRA-2 Reanalysis

MERRA-2 tavgM_2d_lnd_Nx provides monthly mean land surface diagnostics from NASA's global atmospheric reanalysis. The dataset covers 1980 to the present and is produced by NASA's Global Modeling and Assimilation Office using the GEOS model. Data latency is approximately three weeks after the end of each month.

Use Cases

• Modeling baseflow flux and runoff to assess watershed hydrology and flood risk.
• Analyzing surface soil wetness and root zone soil wetness for agricultural drought monitoring.
• Studying soil temperature at six layers to understand permafrost dynamics and thermal regimes.
• Investigating variance of parameters to quantify uncertainty in land surface processes.

Strengths

• Global spatial coverage at 0.625 x 0.5 degree resolution.
• Continuous temporal coverage from 1980 to present, updated monthly.
• Produced by NASA's GMAO using a consistent assimilation model (GEOS 5.12.4).

Limitations

• Data is a model reanalysis product, not direct observations, introducing assimilation biases.
• Spatial resolution may be too coarse for local-scale studies.
• Reprocessing events can alter data, requiring careful version tracking.

Provenance

Source

NASA Global Modeling and Assimilation Office (GMAO).

Collection Method

Produced via the Goddard Earth Observing System Model (GEOS) version 5.12.4 assimilation.

Time Range

1980 to present.

Freshness

Updated monthly with a ~3-week latency.

Geography

Global.