AERMOD is the preferred air quality dispersion model of US-EPA and it is used all over the world as reference model for regulatory purposes.
On August 21, 2019, the U.S. EPA announced revisions to the AERMOD air dispersion model and its component AERMET, the meteorological data preprocessor.
These revisions include the update of AERMOD from version 18081 to version 19191.
AERMOD 19191 includes various bug fixes and some enhacements:
- Bug fixings of some AERMET routines.
- Bug fixings of some AERMOD routines (e.g., background concentration output units; Wet particle deposition; Minimum release height of buoyant line sources; ...).
- The RLINE source type was added to model roadways or similar line-type releases, which uses the dispersion calculations from the R-LINE model.
- The RLINEXT source type has been added to model depressed roadways and roadside barriers; the RLINE source does not have these capabilities.
- ARM2 (Ambient Ratio Method version 2) was extended for application to sources and source groups that include the RLINE and RLINEXT line sources.
- EVENT processing was extended for application to sources and source groups that include RLINE and RLINEXT line sources.
- The URBAN option was extended for application to sources and source groups that include RLINE and RLINEXT line sources.
- The capability to process a buoyant line source in an urban environment was added as an ALPHA option (previously, AERMOD treated a buoyant line source in an urban environment as a source in a rural environment).
AERSCREEN, the recommended screening model for simple and complex terrain for single sources and options for multi-source screening based on AERMOD at the moment is still based on version 16216r.