Global Modeled and Measured Cloudy and Clear Sky Photolysis Rates

Nine global chemistry-climate models provide 4-D gridded fields of photolysis rates for ozone (J-O1D) and nitrogen dioxide (J-NO2) for a nominal day in mid-August 2016. This dataset also includes observed 3-second average measurements from the ATom mission's CAFS instrument over the tropical and northern Pacific Ocean from July 29 to August 23, 2016. The data, produced by the ORNL_CLOUD organization, supports analysis of cloud effects on atmospheric photochemistry.

Use Cases

• Comparing modeled J-O1D and J-NO2 values against high-frequency CAFS instrument measurements to assess model performance.
• Analyzing the impact of clouds on photolysis rates by contrasting all-sky and clear-sky simulation results across latitude, longitude, and pressure levels.
• Using the provided auxiliary data on clouds and ozone column with the included MATLAB scripts to reproduce published analyses of Pacific basin photochemistry.
• Investigating spatial and temporal variability of photolytic rates in remote Pacific regions using the 4-D global model fields.

Strengths

• Includes data from nine distinct global chemistry-climate models, enabling multi-model comparison.
• Pairs global model outputs with high-resolution (3-second average) observational data from the ATom CAFS instrument for validation.
• Provides both all-sky and clear-sky scenarios for the same time period, isolating the effect of clouds and aerosols.

Limitations

• Model data is for a single nominal day in August 2016, limiting temporal analysis of seasonal or long-term trends.
• Sources conflict on the last updated date, with one listing 2017-08-31 and others listing 2026-03-13.
• Specific row counts, file sizes, and a complete list of data columns are not provided by any source.

Provenance

Source

ORNL_CLOUD organization, associated with the ATom (Atmospheric Tomography) mission.

Collection Method

Output from nine global chemistry-climate/transport models and in-situ measurements from the Charged-coupled device Actinic Flux Spectroradiometer (CAFS) instrument.

Time Range

2016-07-29 to 2016-08 23 (measurements); nominal model day is mid-August 2016.

Freshness

2026-03 13:56:33.678950

Geography

Global model fields; measurements focused on remote areas over the tropical and northern Pacific Ocean.