MERRA-2: 3-Hourly Atmospheric Moisture Diagnostics on Pressure Levels

NASA's MERRA-2 reanalysis provides assimilated 3D diagnostics of convective rainwater and precipitation fluxes every three hours from 1980 onward. The collection includes 42 pressure levels and is produced by the Global Modeling and Assimilation Office using the GEOS model. Data is available with a latency of approximately three weeks after the end of each month.

Use Cases

• Model convective precipitation sources based on assimilated rainwater diagnostics.
• Analyze 3D fluxes of ice and liquid precipitation across pressure levels.
• Study atmospheric moisture processes using time-averaged three-hourly data.
• Validate climate model outputs against NASA's reanalysis assimilation.

Strengths

• Data covers a long temporal range from 1980 to the present.
• Provides diagnostics on 42 distinct pressure levels.
• Time-averaged data is available at a high frequency of every three hours.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment.
• Data reprocessing may result in files with different naming conventions.

Provenance

Source

NASA Global Modeling and Assimilation Office (GMAO)

Collection Method

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

Time Range

1980-present

Freshness

Data has a latency of ~3 weeks after the end of a month.

Geography

Global coverage at 0.625 x 0.5 degree resolution.