Air Dispersion Modeling

What is Air Dispersion Modeling?

Air dispersion modeling provides a visual mathematical simulation of how air pollutants disperse in the ambient atmosphere. Based on emissions source and meteorological data as well as topography information, a dispersion model calculates an estimate of the downwind concentration of pollutants as they travel away from emissions sources.

How are dispersion models used?

Dispersion models can be used to determine whether a new source will adversely impact an area or to predict whether the control of an individual source will have a beneficial effect. For example, these models are used to determine compliance with National Ambient Air Quality Standards (NAAQS) and other regulatory requirements, such as New Source Review (NSR) and Prevention of Significant Deterioration (PSD) regulations.

ADEQ Modeling Guidance for Permits 

ADEQ has developed a guidance document to help applicants understand air quality modeling procedures with reguard to Air Quality Permit applications for sources located in Arizona under ADEQ jurisdiction | See Guidance >

ADEQ AERMET Pre-processed Meteorological Data 

Meteorological data was processed with AERMET version 15181, along with AERMINUTE. A minimum wind speed threshold of 0.5 m/s was used to treat winds below the threshold as calms. Data is available for the five-year period of 2009 to 2013, except from Page, Winslow and St. Johns. For those three stations, data is available for 2009 to 2012 and 2014 because monthly one-minute data is missing from June to December in 2013 |  View Data >