Monthly Atmospheric Radiation Diagnostics on 42 Pressure Levels

MERRA-2 provides a global atmospheric reanalysis from 1980 to the present with a latency of about three weeks. This collection, M2TMNPRAD, contains monthly mean assimilations of radiation diagnostics, such as cloud fraction for radiation and air temperature tendencies due to longwave and shortwave radiation, across 42 pressure levels. It is produced by NASA's Global Modeling and Assimilation Office using the Goddard Earth Observing System Model version 5.12.4.

Use Cases

• Validate cloud fraction for radiation parameterizations in climate models against the reanalysis data.
• Analyze air temperature tendency due to longwave radiation to understand atmospheric heating rates.
• Study the variance of key radiation parameters to assess interannual variability and model uncertainty.
• Correlate radiation diagnostics across 42 pressure levels with surface temperature records to investigate vertical energy transport.

Strengths

• Covers a multi-decadal period from 1980 to present, enabling long-term trend analysis.
• Provides data on 42 distinct pressure levels, offering detailed vertical atmospheric profiles.
• Produced by NASA GMAO using the GEOS model, a leading authority in atmospheric reanalysis.

Limitations

• Specific row counts, column counts, and sample sizes are not provided in the description.
• Data is reprocessed, and filename changes can create version management challenges for users.
• The ~3-week latency means data is not real-time, limiting use for current weather monitoring.

Provenance

Source

NASA Global Modeling and Assimilation Office (GMAO).

Collection Method

Assimilation of observational data using the Goddard Earth Observing System Model (GEOS) version 5.12.4.

Time Range

1980 to present.

Freshness

Updated monthly with a latency of ~3 weeks after the end of each month.

Geography

Global coverage at 0.625 x 0.5 degree resolution.