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Air Emissions Modeling

Biogenic Emission Inventory System (BEIS)

First developed in 1988, BEIS estimates volatile organic compound (VOC) emissions from vegetation and nitric oxide (NO) emissions from soils. Because of resource limitations, recent BEIS development has been restricted to versions that are built within the Sparse Matrix Operational Kernel Emissions (SMOKE) system. See the SMOKE website Exitto find the SMOKE Manual Section 2.17 for the latest available description of the version of BEIS included in SMOKE. The SMOKE website also provides the download and installation of the latest version of BEIS.

Download the current BEIS model: Please see the SMOKE website Exit

BEIS Version History

  • BEIS3.61: Developed within the Community Multiscale Air Quality (CMAQ) model to allow for interactions between air quality and meteorology. A version has also been included in SMOKE that can use stand-alone meteorology data rather than data generated simultaneously with a CMAQ run. This version of BEIS has two main updates: It uses the BELD4.1 land use database which incorporates the NLCD. Additionally, leaf temperature is calculated using a canopy model instead of 2 meter temperature. This requires additional variables from the meteorological model compared to BEIS3.14.
  • BEIS3.14: See also Pouliot and Pierce (2009).
  • BEIS3.13: Updated the isoprene emission factor for spruce and revised the light correction factors for isoprene. See also CMAS extended abstract Schwede et al., 2005 entitled Changes to the Biogenic Emissions Inventory System Version 3 and the associated slides.
  • BEIS3.12: Revises the soil NO algorithm based on the work of Yienger and Levy (1995) to include temperature and precipitation adjustment factors, a fertilizer adjustment factor, and a canopy adjustment factor. See also BEIS documentation included for the Clean Air Interstate Rule.
  • BEIS3.11: Revised soil NO algorithm to better distinguish between agricultural and nonagricultural land, and to limit adjustments from temperature, precipitation, fertilizer application, and crop canopy to the growing season and to areas of agriculture. A leaf shading algorithm was added for estimating methanol emissions from non-forested areas.
  • BEIS3.10: Developed for the 2002 release of the Community Multiscale Air Quality (CMAQ) modeling system. Included a 1-km vegetation database that resolved forest canopy coverage by tree species; emission factors for 34 chemicals including 14 monoterpenes and methanol; a soil NO algorithm dependent on soil moisture, crop canopy coverage, and fertilizer application; and, speciation for the CB4, RADM2, and SAPRC99 mechanisms.
  • BEIS3.09: First incorporated into SMOKE. See Vukovich and Pierce, 2002.
  • BEIS2.3: Prior PC-based version.