MERRA-2: Country-Level Monthly PM2.5 Concentrations with Population Weighting

Country-level monthly mean surface concentrations of fine particulate matter (PM2.5), derived from NASA's MERRA-2 aerosol reanalysis model. The data collection includes separate files for raw and population-weighted PM2.5 values for countries and territories. This value-added product is provided by NASA's Global Modeling and Assimilation Office (GMAO) and distributed via the Goddard Earth Sciences Data and Information Services Center (GES DISC).

Use Cases

• Analyze long-term trends in national air pollution exposure based on monthly PM2.5 means.
• Model population-weighted health risk from particulate matter based on the provided weighting.
• Validate regional climate or air quality models using satellite-derived aerosol component data.
• Study the contribution of different aerosol components (e.g., dust, sulfate) to total PM2.5.

Strengths

• Data is derived from the established MERRA-2 reanalysis model, a NASA product.
• Includes both raw and population-weighted PM2.5 concentrations for comparative analysis.
• PM2.5 is calculated from the sum of five individual aerosol components as per cited methodology.

Limitations

• Column-level documentation is absent; field semantics must be inferred after download.
• Row count and spatial resolution details are unknown, which may limit suitability assessment.

Provenance

Source

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

Collection Method

Derived from the MERRA-2 aerosol monthly product M2TMNXAER_5.12.4, recast from the native model grid.

Time Range

Monthly means; specific temporal coverage is not provided in the input.

Freshness

Last updated 2026-03 13 00:42:06.246077; freshness should be verified.

Geography

Country-level and territories; global coverage is likely.