MERRA-2: NASA Global Atmospheric Reanalysis with Hourly Diurnal Means

MERRA-2 provides monthly diurnal means of key meteorological diagnostics at popular vertical levels, such as air temperature at 2-meter and wind components at 50-meter. The dataset covers the period from 1980 to the present and is produced by NASA's Global Modeling and Assimilation Office using the GEOS model version 5.12.4. Data is available with a latency of approximately three weeks after the end of each month.

Use Cases

• Analyze long-term climate trends based on monthly diurnal means of air temperature and pressure.
• Model atmospheric circulation patterns based on wind component data at multiple vertical levels.
• Study hydrological cycles based on total precipitable water vapor and its ice/liquid components.
• Validate satellite-era weather models using the assimilated, time-averaged reanalysis data.

Strengths

• Data spans from 1980 to the present, providing a continuous record for the satellite era.
• Includes diagnostics at popularly used vertical levels, such as 2-meter temperature and 50-meter wind.
• Produced by NASA's Global Modeling and Assimilation Office (GMAO), an authoritative source.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count is unknown, which may limit suitability assessment for specific ML tasks.

Provenance

Source

National Aeronautics and Space Administration (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

Updated with a latency of ~3 weeks after the end of a month; last metadata update was 2026-03-13.

Geography

Global, at 0.625 x 0.5 degree resolution