Global Atmospheric Turbulence Diagnostics from NASA's MERRA-2 Reanalysis

MERRA-2 provides 3-hourly, 3-dimensional assimilated turbulence diagnostics across 73 model layer edges from 1980 to present. NASA's Global Modeling and Assimilation Office produces this data using the GEOS model version 5.12.4. The collection includes parameters like total scalar diffusivity and momentum diffusivity.

Use Cases

• Analyze temporal trends in total scalar diffusivity across model layers to study atmospheric mixing.
• Validate turbulence parameterization schemes in climate models using the momentum diffusivity from Louis feature.
• Correlate the Richardson number from Louis with other reanalysis variables to diagnose atmospheric stability.
• Map the spatial distribution of total momentum diffusivity at different pressure levels for regional climate studies.

Strengths

• Covers a long time range from 1980 to present, enabling long-term climate studies.
• Provides high temporal resolution data at 3-hourly intervals.
• Includes diagnostics across 73 vertical model layer edges for detailed atmospheric profiling.

Limitations

• Data has a latency of approximately three weeks after the end of each month, limiting real-time analysis.
• Reprocessing events create filename inconsistencies that require user attention.
• The spatial resolution of 0.625 x 0.5 degrees may be coarse for some mesoscale applications.

Provenance

Source

NASA Global Modeling and Assimilation Office (GMAO) via GES DISC.

Collection Method

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

Time Range

1980 to present.

Freshness

Updated monthly with a ~3-week latency.

Geography

Global coverage at 0.625 x 0.5 degree resolution.