MERRA-2 M2I1NXASM: Hourly Global Atmospheric Reanalysis Data

MERRA-2 inst1_2d_asm_Nx is an hourly, instantaneous collection of assimilated meteorological diagnostics from NASA's Global Modeling and Assimilation Office. It provides global data on parameters like temperature, wind components, surface pressure, and total precipitable water from 1980 to the present. The dataset is produced using the Goddard Earth Observing System Model version 5.12.4 and has a latency of approximately three weeks after the end of each month.

Use Cases

• Modeling near-surface atmospheric conditions based on 2-meter and 10-meter temperature data
• Analyzing wind patterns using 2-meter, 10-meter, and 50-meter wind component data
• Studying atmospheric moisture content based on total precipitable water data
• Investigating surface pressure variations for weather system analysis
• Developing time-series forecasting models for hourly global meteorological parameters

Strengths

• Data covers a long temporal range from 1980 to the present
• Provides hourly instantaneous data points at 00:00, 01:00, ... 23:00 UTC
• Produced by NASA's Global Modeling and Assimilation Office (GMAO), an authoritative source
• Likely has a global spatial coverage at 0.625 x 0.5 degree resolution

Limitations

• Column-level documentation is absent; field semantics must be inferred after download
• Row count is unknown, which may limit suitability assessment for large-scale ML projects
• Data reprocessing has occurred, and filename changes may complicate version tracking

Provenance

Source

National Aeronautics and Space Administration (NASA) Global Modeling and Assimilation Office

Collection Method

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

Time Range

1980-present

Freshness

Updated as of 2026-03-13; data has a latency of ~3 weeks after the end of a month.

Geography

Global