CALPUFF is an advanced non-steady-state meteorological and air quality modeling system. The model has been adopted by the U.S. Environmental Protection Agency (U.S. EPA) in its Guideline on Air Quality Models as the preferred model for assessing long range transport of pollutants and their impacts on Federal Class I areas and on a case-by-case basis for certain near-field applications involving complex meteorological conditions. The modeling system consists of three main components and a set of preprocessing and post processing programs. The main components of the modeling system are CALMET (a diagnostic 3-dimensional meteorological model), CALPUFF (an air quality dispersion model), and CALPOST (a post processing package). Each of these programs has a graphical user interface (GUI).


The CALPUFF model simulates the effects of time and space-varying meteorological conditions on pollution transport, transformation and removal.

Latest Version Version 6.42 August 2011
State of Development Released and updated

Development Contact

Al Klausmann
+1 978 970-5600
Atmospheric Studies Group, Earth Tech
TRC Environmental Corp. 650 Suffolk Street Lowell, MA 01854


Outcome Areas Environmental
Management Domains Air Quality
Subdomains Air Quality Modelling
Spatial Resolutions Unknown
Spatial Extents Land or Business Unit, Local (i.e. Catchment or District)
Spatial Dimensions 3D
Temporal Resolutions Hours, Days, Months
Temporal Extents Hours, Days, Months
Steady State or Dynamic Unknown
Level of Integration Environmental

Input & Output Data

Key Input Data Meterological
Input Data Formats ASCI
Key Output Data Runoff Fluxes of contaminants
Output Data Formats ASCI, Image File(s)


Open/Closed Source Open Source
Licence Type

User Information

Operating Systems Dos executable
User Interface Graphical desktop
Ease of Use Difficult Requires preparation of multiple data files and linking with supporting models
Use in Policy Process Plan (Policy Formulation), Do (Policy Implementation), Review (Issue Identification)

A User's Guide for the CALPUFF Dispersion Model

Frequently Asked Questions

Support Three day training course by Atmospheric Studies Group, Earth Tech -

Technical Considerations

Programming Language Fortran
Analytical Techniques Input/output
Model Structure

calpuff 3

Keywords atmosphere, air quality, pollution, meteorology

Key References

Bennett, M.J, M.E. Yansura, I.G. Hornyik, J.M. Nall, D.G. Caniparoli and C.G. Ashmore, 2002. Evaluation of the CALPUFF Long-range Transport Screening Technique by Comparison to Refined CALPUFF Results for Several Power Plants in Both the Eastern and Western United States. Proceedings of the Air & Waste Management Association's 95th Annual Conference, June 23-27, 2002; Baltimore, MD. Paper #43454.

Levy, JI; Spengler, JD; Hlinka, D; Sullivan, D; Moon, D (2002): Using CALPUFF to evaluate the impacts of power plant emissions in Illinois: mode sensitivity and implications. Atmos. Environ. Vol 36(6):1063-1075. 3) Zhou, Y; Levy, JI; Hammitt, JK; Evans, JS (2003): Estimating population exposure to power plant emissions using CALPUFF: a case study in Beijing, China. Atmos. Environ. Vol. 37(6):815-826

Associated Case Studies

  • CALPUFF - Sulphur dioxide ambient modelling

    This paper summarises a study carried out for Carter Holt Harvey at Kinleith Pulp and Paper Mill (Tokoroa, New Zealand) which compared two different types of atmospheric dispersion model with actual ambient monitoring data for SO2.  One of these models is CALPUFF.                       

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