Skip to Main Content U.S. Department of Energy
Atmospheric Science & Global Change

PNNL Capabilities in WRF-Chem

photo collage depicting the types of particulates being modeled

Capabilities added to WRF-Chem (as of July 2010)

Photochemistry

  • CBM-Z gas-phase mechanism [Zaveri and Peters, 1999]
  • KPP version of CBM-Z
  • Compatibility of CBM-Z with the Model of Emissions of Gases and Aerosols from Nature (MEGAN) biogenic emission module (in collaboration with NCAR)
  • Fast-J photolysis module [Wild et al., 2000; Barnard et al., 2004]

Particulates

  • Model for Simulating Aerosol Interactions and Chemistry (MOSAIC) aerosol model that employs the sectional approach for the size distribution and internal mixing [Zaveri et al., 2005a,b, 2008]
  • On-line treatments for sea-salt [a modified version of Gong et al., 1997a,b] and dust [Shaw et al., 2008] emissions module compatible with MOSAIC
  • Coupling GOCART dust emissions module to MOSAIC [Zhao et al. 2010]
  • Generalized driver for dry deposition of particulates that enables several paramerizations to be used in the same way for both MADE/SORGAM and MOSAIC [Fast et al., 2010], in collaboration with Stuart McKeen (NOAA)
  • MOSAIC modified to include treatment of secondary organic aerosols based on the volatility basis set approach [Shrivastava et al. 2008]
  • Coupled MOSAIC to SAPRC-99 photochemical mechanism, in collaboration with Pablo Saide (Univ. Iowa)
  • Generalized aerosol pointer array system that groups aerosols by composition, size bin, type (internal vs. external), and phase (interstitial, cloud water, ice, etc.) that can be employed by other aerosol models

Optical properties

  • Generalized driver that computes aerosol optical depth, single scattering albedo, and asymmetry parameter for both MADE/SORGAM and MOSAIC using either volume averaging, Maxwell-Garnett, or shell-core mixing rules

Radiative forcing

  • Inclusion of direct, semi-direct, first indirect, and second indirect effects of aerosols

Aerosol-radiation-cloud-chemistry feedbacks

  • Through coupling with the Goddard shortwave radiation parameterization using aerosol optical depth, single scattering albedo, and asymmetry factor derived from MOSAIC particulates and Mie theory [Fast et al., 2006; Ghan et al., 2001b Gustafson et al. 2007, Chapman et al. 2009] and the Lin et al. microphysics parameterization
  • Aerosol-radiative feedbacks extended to RRTMG shortwave and longwave radiation parameterization

Cloud-aerosol interactions

  • Through coupling with the Lin et al. microphysics parameterization [Gustafson et al., 2007; Chapman et al., 2008] that include prognostic treatments of cloud droplet number and activated (cloud-phase) aerosol species, aerosol activation and resuspension [Ghan et al., 2001a; Zhang et al., 2002], bulk cloud chemistry [Fahey and Pandis, 2001], and in-cloud and below-cloud wet removal of particulates and trace gases [Easter et al., 2004]
  • Aerosol-cloud interactions extended to include MADE/SORGAM aerosol module
  • Extended aerosol-cloud interactions to include Morrison and Thompson microphysics parameterizations, in collaboration with NCAR

Compatibility

  • PNNL modules distributed with WRF version 3.2

Planned capabilities for WRF-Chem

  • Porting CAM5 physics suite into WRF
  • Ice-Aerosol interactions
  • MOSAIC-Ext: a version of MOSAIC that treats both external and internal mixing states

WRF-Chem

Atmospheric Science & Global Change

Fundamental & Computational Sciences