Global Atmospheric Carbon Monoxide and Ozone Mixing Ratios at 72 Model Layers

MERRA-2 inst3_3d_chm_Nv provides assimilated 3D, 3-hourly instantaneous data for carbon monoxide and ozone mixing ratios across 72 vertical model layers. NASA's Global Modeling and Assimilation Office (GMAO) produced this reanalysis using the GEOS 5.12.4 model. The dataset covers the period from 1980 to the present, with data available every three hours (e.g., 00:00, 03:00 UTC).

Use Cases

• Analyze vertical profiles of ozone mixing ratio across 72 model layers to study stratospheric-tropospheric exchange.
• Model global transport patterns of carbon monoxide mixing ratio using 3-hourly instantaneous assimilation data.
• Validate satellite-derived atmospheric composition products against assimilated model-level data for carbon monoxide and ozone.
• Investigate diurnal cycles in trace gas concentrations using data available at 00:00, 03:00, 06:00, etc. UTC.
• Study long-term trends in atmospheric pollutants from 1980 to present using the continuous reanalysis record.

Strengths

• Provides data at 72 vertical model layers, enabling detailed atmospheric profile analysis.
• Offers a continuous temporal record from 1980 to the present, supporting long-term climate studies.
• Data is available at a 3-hourly instantaneous frequency (00:00, 03:00 UTC, etc.) for diurnal cycle analysis.
• Produced by NASA GMAO using the GEOS 5.12.4 model, an authoritative source for reanalysis data.

Limitations

• Data has an approximate latency of 3 weeks after the end of a month, limiting near-real-time applications.
• The spatial resolution is 0.625 x 0.5 degrees, which may be coarse for regional-scale process studies.
• Reprocessing events occur, and filenames for reprocessed data differ, requiring careful version tracking.

Provenance

Source

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

Collection Method

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

Time Range

1980 to present.

Freshness

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

Geography

Global coverage at 0.625 x 0.5 degree resolution.