Global Atmospheric Radiation Diagnostics on 42 Pressure Levels

MERRA-2 provides 3-hourly assimilated radiation diagnostics across 42 atmospheric pressure levels, including cloud fraction for radiation and temperature tendencies. The dataset spans from 1980 to the present, produced by NASA's Global Modeling and Assimilation Office using the GEOS model. Data is updated with a latency of approximately three weeks after each month.

Use Cases

• Analyze cloud fraction for radiation data to validate satellite-derived cloud products and improve climate model cloud schemes.
• Model air temperature tendency due to longwave radiation across pressure levels to study atmospheric heating rates.
• Use the 3-hourly time-averaged data to initialize or evaluate high-temporal-resolution numerical weather prediction models.
• Investigate spatial patterns of shortwave radiation diagnostics at the 0.625 x 0.5 degree resolution for regional climate studies.

Strengths

• Covers a long temporal range from 1980 to present, enabling long-term climate trend analysis.
• Provides data on 42 distinct pressure levels, offering detailed vertical atmospheric profiles.
• Global spatial coverage at a 0.625 x 0.5 degree latitude/longitude resolution.

Limitations

• Data is reprocessed, leading to filename inconsistencies between original and updated versions which can complicate version tracking.
• The ~3-week latency for updates prevents near-real-time analysis or operational forecasting use.

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

Updated monthly with a ~3-week latency.

Geography

Global