WRF-Chem — Weather Research and Forecasting model with Chemistry

WRF-Chem — Weather Research and Forecasting model with Chemistry#

Overview#

WRF-Chem is the Weather Research and Forecasting (WRF) model coupled with chemistry. It is a fully coupled online air-quality model, meaning that the meteorological and chemical fields evolve simultaneously and interact with each other (e.g. aerosol–radiation feedbacks).

WRF-Chem is a regional limited-area model with nested-domain capability, making it well suited for high-resolution emission inversion studies at continental to urban scales. It supports a wide range of chemical mechanisms and aerosol modules.

Key features relevant to atmospheric inversion#

  • Online coupling — meteorology and chemistry evolve consistently within the same time step, avoiding interpolation errors from offline transport.

  • High resolution — domains can be configured at sub-kilometre resolution.

  • Flexible chemistry — multiple gas-phase and aerosol mechanisms are available (MOZART, RADM2, CBMZ, …).

  • Emission flexibility — anthropogenic, biogenic, and fire emissions can be specified externally.

Key references#

  • Grell et al. (2005) — the original WRF-Chem paper: Fully coupled “online” chemistry within the WRF model, Atmos. Environ., 39, 6957–6975, doi:10.1016/j.atmosenv.2005.04.027.

  • Skamarock et al. (2021) — the WRF model description: A Description of the Advanced Research WRF Model Version 4.3, NCAR Technical Note NCAR/TN-556+STR, doi:10.5065/1dfh-6p97.

Official resources#

CIF integration#

The CIF WRF-Chem plugin is located under pycif.plugins.models.wrfchem.

Note

The WRF-Chem plugin is currently at a preliminary stage of integration into CIF. Some features (e.g. inline flux optimisation, ensemble member handling) require pre-processing outside CIF. The plugin has been developed and tested at DLR (Germany) in the context of regional CO₂ inversion studies.

Preprocessing of WRF input files (wrfinput, wrfbdy, wrfchemi) is expected to be handled externally before CIF launches the model.