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Record Search Query: ServiceParameters>MODELS>ATMOSPHERIC CHEMISTRY MODELS

Second-order Closure Integrated Puff Model
Entry ID: SCIPUFF-Model
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Abstract: SCIPUFF (Second-order Closure Integrated Puff) model is a Lagrangian puff dispersion model developed by Titan's ARAP Group that uses a collection of Gaussian puffs to represent an arbitrary, three-dimensional time-dependent concentration. The turbulent diffusion parameterization is based on turbulence closure theory, providing a direct relationship between the predicted dispersion rate and turbulent velocity statistics of the wind field. In addition to the average concentration value, the closure model also provides a prediction of the statistical variance in the concentration field resulting from the random fluctuations in the wind field. The closure approach also provides a direct representation for the effect of averaging time. SCIPUFF has been incorporated into the Defense Threat Reduction Agency's (DTRA) Hazard Prediction and Assessment Capability (HPAC) software. HPAC is utilized for planning and analysis as well as in the field by military personnel to rapidly determine consequences of dispersing chemical, nuclear and biological agents. SCIPUFF has been validated against a number of laboratory and field experiments, demonstrating its usefulness for non-military applications. It has been recommended as an alternative model by the EPA which can be used on a case-by-case basis for regulatory applications. The publicly available version of SCIPUFF is the same version incorporated in HPAC except that the proprietary and developmental features have been disabled. SCIPUFF runs on a PC with a user-friendly Graphical User Interface (GUI).
Related URL
Description: Support Center for Regulatory Air Models Home Page.

Description: Model Documentation

Description: Dispersion modeling uses mathematical formulations to characterize the
atmospheric processes that disperse a pollutant emitted by a source. Based on
emissions and meteorological inputs, a dispersion model can be used to predict
concentrations at selected downwind receptor locations. These air quality
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. These
models are addressed in Appendix A of EPA's Guideline on Air Quality Models
(also published as Appendix W of 40 CFR Part 51), which was originally
published in April 1978 to provide consistency and equity in the use of
modeling within the U.S. air quality management system. These guidelines are
periodically revised to ensure that new model developments or expanded
regulatory requirements are incorporated.

Description: Receptor Models

Receptor models are mathematical or statistical procedures for identifying and
quantifying the sources of air pollutants at a receptor location. Unlike
photochemical and dispersion air quality models, receptor models do not use
pollutant emissions, meteorological data and chemical transformation mechanisms
to estimate the contribution of sources to receptor concentrations. Instead,
receptor models use the chemical and physical characteristics of gases and
particles measured at source and receptor to both identify the presence of and
to quantify source contributions to receptor concentrations. These models are
therefore a natural complement to other air quality models and are used as part
of State Implementation Plans (SIPs) for identifying sources contributing to
air quality problems. The EPA has developed the Chemical Mass Balance (CMB) and
UNMIX models as well as the Positive Matrix Factorization (PMF) method for use
in air quality management. CMB fully apportions receptor concentrations to
chemically distinct source-types depending upon the source profile database,
while UNMIX and PMF internally generate source profiles from the ambient data.
Service Citation
Title: Second-order Closure Integrated Puff Model
Provider: Titan Corporation, L3
ISO Topic Category
Access Constraints
SCIPUFF Version 1.2PD and its technical documentation are available by contacting: Dr. R. Ian Sykes, Titan Research & Technology, ARAP Group, P.O. Box 2229, Princeton, NJ 08543-2229. Phone: (609) 452- 2950.
Use Constraints
Titan Corporation shall not be liable for any fault or failure of SCIPUFF or
for any consequences whatsoever of any fault or failure. By proceeding with the
download, the recipient agrees to these conditions.
Service Provider
Titan Group, L-3 Communications

Service Provider Personnel
Phone: (609) 452-2950
Email: webmasters at
Contact Address:
L-3 Communications
Titan Group
P.O. Box 2229
City: Princeton
Province or State: NJ
Postal Code: 08543
Country: USA
Distribution Media
Distribution_Media: Electronic/Download
Distribution_Size: 111KB
Distribution_Format: zip
Fees: None
Phone: (609) 452-2950
Fax: (609) 452-2856
Email: SCIPUFF-info at
Contact Address:
The Titan Corporation
P.O. Box 2229
City: Princeton
Province or State: NJ
Postal Code: 08543-2229
Country: USA

Phone: (301) 614-6898
Fax: 301-614-5268
Email: Tyler.B.Stevens at
Contact Address:
NASA Goddard Space Flight Center
Global Change Master Directory
City: Greenbelt
Province or State: MD
Postal Code: 20771
Country: USA
Sykes, R. I., C. P. Cerasoli and D. S. Henn (1999). The representation of
dynamic flow effects in a Lagrangian puff dispersion model, J. Haz. Mat., 64,

Sykes, R. I., S. F. Parker, D. S. Henn, C. P. Cerasoli and L. P. Santos (1998).
PC-SCIPUFF Version 1.1PD.1 Technical Documentation. ARAP Report No. 718. Titan
Corporation, Titan Research & Technology Division, ARAP Group, P.O. Box 2229,
Princeton, NJ, 08543-2229.

Sykes, R. I. and R. S. Gabruk (1997). A second-order closure model for the
effect of averaging time on turbulent plume dispersion, J. Appl. Met., 36,

Sykes, R. I., D. S. Henn, S. F. Parker and R. S. Gabruk (1996). SCIPUFF - A
generalized hazard dispersion model. Ninth Joint Conference on the Applications
of Air Pollution Meteorology with A&WMA, American Met. Soc.

Sykes, R. I. and D. S. Henn (1995). Representation of velocity gradient effects
in a Gaussian puff model. J. Appl. Met., 34, 2715-2723.

Sykes, R. I., S. F. Parker, D. S. Henn and W. S. Lewellen (1993). Numerical
simulation of ANATEX tracer data using a turbulence closure model for
long-range dispersion, J. Appl. Met., 32, 929-947.
Creation and Review Dates
SERF Creation Date: 2006-04-07
SERF Last Revision Date: 2010-04-27
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