Global Aerosol Mixing Ratio Analysis Increments from MERRA-2 Reanalysis

1980 to present atmospheric reanalysis data provides 3-hourly, 3-dimensional aerosol mixing ratio analysis increments at 72 model layers. NASA's Global Modeling and Assimilation Office (GMAO) produced this dataset using the Goddard Earth Observing System Model (GEOS) version 5.12.4. It covers the globe at a 0.625 x 0.5 degree resolution with a latency of approximately three weeks.

Use Cases

• Modeling the vertical transport of black carbon, dust, organic carbon, sea salt, and sulfate aerosols across 72 atmospheric layers.
• Assimilating 3-hourly aerosol analysis increments from 00:00 to 21:00 UTC into regional climate models.
• Analyzing long-term trends in aerosol composition and concentration from 1980 to the present.
• Validating satellite-derived aerosol optical depth measurements against model-level reanalysis data.
• Studying the spatial distribution of specific aerosol types at a 0.625 x 0.5 degree global grid resolution.

Strengths

• Covers a multi-decadal period from 1980 to present, enabling long-term trend analysis.
• Provides high temporal resolution with 3-hourly instantaneous data snapshots.
• Offers detailed vertical profiling with data across 72 model layers from surface to top of atmosphere.
• Global spatial coverage at a consistent 0.625 x 0.5 degree latitude/longitude grid.

Limitations

• Data has a latency of approximately three weeks after the end of a month, not suitable for real-time monitoring.
• Analysis increments represent model corrections, requiring understanding of the underlying GEOS assimilation system for correct interpretation.
• Reprocessing events change filenames and potentially data values, complicating version tracking.

Provenance

Source

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

Collection Method

Produced by the Goddard Earth Observing System Model (GEOS) version 5.12.4 atmospheric reanalysis and data assimilation system.

Time Range

1980 to present.

Freshness

Updated monthly with a ~3-week latency.

Geography

Global.