Dataset Information

Evaluating the Impact of Chemical Complexity and Horizontal Resolution on Tropospheric Ozone Over the Conterminous US With a Global Variable Resolution Chemistry Model.

ABSTRACT: A new configuration of the Community Earth System Model (CESM)/Community Atmosphere Model with full chemistry (CAM-chem) supporting the capability of horizontal mesh refinement through the use of the spectral element (SE) dynamical core is developed and called CESM/CAM-chem-SE. Horizontal mesh refinement in CESM/CAM-chem-SE is unique and novel in that pollutants such as ozone are accurately represented at human exposure relevant scales while also directly including global feedbacks. CESM/CAM-chem-SE with mesh refinement down to ∼14 km over the conterminous US (CONUS) is the beginning of the Multi-Scale Infrastructure for Chemistry and Aerosols (MUSICAv0). Here, MUSICAv0 is evaluated and used to better understand how horizontal resolution and chemical complexity impact ozone and ozone precursors over CONUS as compared to measurements from five aircraft campaigns, which occurred in 2013. This field campaign analysis demonstrates the importance of using finer horizontal resolution to accurately simulate ozone precursors such as nitrogen oxides and carbon monoxide. In general, the impact of using more complex chemistry on ozone and other oxidation products is more pronounced when using finer horizontal resolution where a larger number of chemical regimes are resolved. Large model biases for ozone near the surface remain in the Southeast US as compared to the aircraft observations even with updated chemistry and finer horizontal resolution. This suggests a need for adding the capability of replacing sections of global emission inventories with regional inventories, increasing the vertical resolution in the planetary boundary layer, and reducing model biases in meteorological variables such as temperature and clouds.

SUBMITTER: Schwantes RH

PROVIDER: S-EPMC9286600 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature

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Publications

Evaluating the Impact of Chemical Complexity and Horizontal Resolution on Tropospheric Ozone Over the Conterminous US With a Global Variable Resolution Chemistry Model.

Schwantes Rebecca H RH Lacey Forrest G FG Tilmes Simone S Emmons Louisa K LK Lauritzen Peter H PH Walters Stacy S Callaghan Patrick P Zarzycki Colin M CM Barth Mary C MC Jo Duseong S DS Bacmeister Julio T JT Neale Richard B RB Vitt Francis F Kluzek Erik E Roozitalab Behrooz B Hall Samuel R SR Ullmann Kirk K Warneke Carsten C Peischl Jeff J Pollack Ilana B IB Flocke Frank F Wolfe Glenn M GM Hanisco Thomas F TF Keutsch Frank N FN Kaiser Jennifer J Bui Thao Paul V TPV Jimenez Jose L JL Campuzano-Jost Pedro P Apel Eric C EC Hornbrook Rebecca S RS Hills Alan J AJ Yuan Bin B Wisthaler Armin A

Journal of advances in modeling earth systems 20220622 6

A new configuration of the Community Earth System Model (CESM)/Community Atmosphere Model with full chemistry (CAM-chem) supporting the capability of horizontal mesh refinement through the use of the spectral element (SE) dynamical core is developed and called CESM/CAM-chem-SE. Horizontal mesh refinement in CESM/CAM-chem-SE is unique and novel in that pollutants such as ozone are accurately represented at human exposure relevant scales while also directly including global feedbacks. CESM/CAM-che ...[more]

PMID: 35864945

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Dataset Information

Evaluating the Impact of Chemical Complexity and Horizontal Resolution on Tropospheric Ozone Over the Conterminous US With a Global Variable Resolution Chemistry Model.

Publications

Evaluating the Impact of Chemical Complexity and Horizontal Resolution on Tropospheric Ozone Over the Conterminous US With a Global Variable Resolution Chemistry Model.

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