Data contributed by EPA researchers to the manuscript "Estimating US background ozone levels using data fusion"

The EPA/ORD/CEMM-contributed dataset consisted of hourly CMAQ output for all model species from a 2017 simulation over the northern hemisphere along a boundary curtain of a 36 km modeling domain specified over the CONUS. The horizontal and vertical extent of the 36 km modeling domain was specified by the external collaborator and was defined by 524 boundary grid cells and 34 vertical layers. The number of output species from the 2017 hemispheric CMAQ simulation was 191 through to September 23, 2017 and 213 starting September 24, 2017.

The EPA/OAR/OAQPS-contributed dataset consistent of hourly gridded CMAQ output for surface ozone concentrations from four model simulations for the year 2016. Two of these simulations were performed over the northern hemisphere at a horizontal resolution of 108 km and the other two simulations were performed over the CONUS at a horizontal resolution of 12 km. This dataset is not publicly accessible because: The size of the data provided to the external researchers (>1TB) exceeds ScienceHub limits. It can be accessed through the following means: Data can be requested by contacting hogrefe.christian@epa.gov (EPA/ORD/CEMM-contributed dataset) and henderson.barron@epa.gov (EPA/OAR/OAQPS-contributed dataset) and providing an external hard to which the data can then be copied by staff at the National Computing Center. 

The model simulations are stored on the /asm archival system accessible through the atmos high-performance computing (HPC) system.  Due to data management policies, files on /asm are subject to expiry depending on the template of the project. Files not requested for extension after the expiry date are deleted permanently from the system. 

Location of EPA/ORD/CEMM-provided CMAQ model output data on asm:
•	/asm/grc/NRT_WRF_CMAQ/model_outputs/nhemi108/cctm.conc
•	/asm/MOD3EVAL/css/NRT/data/gatech/bc
•	/asm/MOD3EVAL/css/NRT/data/gatech/scripts
•	/asm/MOD3EVAL/css/NRT/data/gatech/metbdy3d

Location of EPA/OAR/OAQPS-provided CMAQ model output data on asm:
•	/asm/ROMO/global/CMAQv5.2/2016fe_hemi_cb6_16jh/108km/output
•	/asm/ROMO/global/CMAQv5.2.1/2016fe_hemi_cb6_16jh/108km/ZUSA/output
•	/asm/ROMO/2016platform/CMAQv521/2016fe_cb6r3_ae6nvpoa_16j/12US2/output
•	/asm/ROMO/2016platform/CMAQv521/2016fe_zusa_cb6r3_ae6nvpoa_16j/12US2/output. Format: The CMAQ model output datasets used for the analysis presented in this manuscript and documented here were provided by scientists in EPA/ORD/CEMM and EPA/OAR/OAQPS. 

The EPA/ORD/CEMM-contributed dataset consisted of hourly CMAQ output for all model species from a 2017 simulation over the northern hemisphere along a boundary curtain of a 36 km modeling domain specified over the CONUS. The horizontal and vertical extent of the 36 km modeling domain was specified by the external collaborator and was defined by 524 boundary grid cells and 34 vertical layers. The number of output species from the 2017 hemispheric CMAQ simulation was 191 through to September 23, 2017 and 213 starting September 24, 2017.

The EPA/OAR/OAQPS-contributed dataset consistent of hourly gridded CMAQ output for surface ozone concentrations from four model simulations for the year 2016. Two of these simulations were performed over the northern hemisphere at a horizontal resolution of 108 km and the other two simulations were performed over the CONUS at a horizontal resolution of 12 km.

The data files with the CMAQ model output provided to the external researchers use the ioapi/netcdf format. Documentation of this format, including definitions of the geographical projection attributes contained in the file headers, are available at https://www.cmascenter.org/ioapi/documentation/all_versions/html. 

This dataset is associated with the following publication:
Skipper, T.N., Y. Hu, M.T. Odman, B. Henderson, C. Hogrefe, R. Mathur, and A. Russell. EST Publication: Estimating US background ozone levels using data fusion.   ENVIRONMENTAL SCIENCE & TECHNOLOGY. American Chemical Society, Washington, DC, USA, 55(8): 4504-4512, (2021).

Tags: air-quality-model-evaluation, background-ozone, data-fusion
Organization: U.S. Environmental Protection Agency