Monthly Diurnal Land Surface Forcings from NASA MERRA-2 Reanalysis

1980 to present monthly diurnal means of land surface forcing parameters, such as bias-corrected precipitation and surface radiation. This time-averaged 2D data collection is produced by NASA's Global Modeling and Assimilation Office (GMAO) using the GEOS model. Data is available at a 0.625 x 0.5 degree resolution with a latency of about three weeks.

Use Cases

• Model validation by comparing simulated bias-corrected precipitation and shortwave radiation fields against these reanalysis estimates.
• Analyzing diurnal cycles in land surface energy budgets using hourly time-stamped surface longwave radiation data.
• Studying long-term trends in surface forcing parameters like precipitation across the global 0.625 x 0.5 degree grid from 1980 onward.

Strengths

• Continuous temporal coverage from 1980 to the present, providing over 40 years of data.
• High spatial resolution at a 0.625 x 0.5 degree global grid.
• Provides hourly diurnal means for each month, capturing intra-day variability.

Limitations

• Data is a reanalysis product, meaning it is a model estimate constrained by observations, not direct measurement.
• Latency of approximately three weeks after the end of each month limits near-real-time applications.
• Spatial resolution, while high for global reanalysis, may be too coarse for local-scale studies.

Provenance

Source

NASA Global Modeling and Assimilation Office (GMAO) via the Goddard Earth Sciences Data and Information Services Center (GES DISC).

Collection Method

Produced using the Goddard Earth Observing System Model (GEOS) version 5.12.4 data assimilation system.

Time Range

1980 - Present

Freshness

Updated monthly with a ~3-week latency.

Geography

Global