The Offshore and Coastal Dispersion (OCD) Model: Revisions and Evaluations
The Offshore and Coastal Dispersion (OCD) Model simulates plume dispersion and transport from offshore point, area, or line sources to receptors on land or water. The OCD model is an hour-by-hour steady state Gaussian model with enhancements that consider the differences between overwater and overland dispersion characteristics, the sea-land interface, and platform aerodynamic effects. A revised OCD model (Version 4) (or OCD/4) has been developed that includes modifications to boundary layer parameterizations and dispersion model assumptions. An overview of the physical and theoretical aspects of the model is given, along with the results of a statistical model evaluation exercise that compares the revised model (OCD/4) with the earlier OCD model (Version 3) (or OCD/3). Data from four field experiments (Ventura, Pismo Beach, and Carpinteria, California; Cameron, Louisiana) are used to evaluate the model performance. The reader is referred to the report by DiCristofaro and Hanna (1989) for detailed discussions of the points that are only briefly reviewed in this paper.
KeywordsBeach Hunt Line Source eThis
Unable to display preview. Download preview PDF.
- Briggs, G.A., Diffusion Estimates for Small Emissions, ATDL Cont. 79, ATDL, Oak Ridge, TN (1973).Google Scholar
- DiCristofaro, D. C., D. Strimaitis, B. Greene, R. Yamartino, D. Godden, T. Lavery, and B. Egan, EPA Complex Terrain Model Development Program: Fifth Milestone Report-1984. EPA600/3-84-110, U.S.EPA, RTP, NC (1986).Google Scholar
- DiCristofaro, D. C. and S.R. Hanna, OCD: The Offshore and Coastal Dispersion Model Volume I: User’s Guide, U.S. MMS, Herndon, VA (1989).Google Scholar
- Gifford, F.A., An Outline of Theories of Diffusion in the Lower Layers of the Atmosphere in: “Meteorology and Atomic Energy-1968,” D.H. Slade ed. USAEC Report TID-24190 (1968).Google Scholar
- Hanna, S.R. and D.C. DiCristofaro, Development and Evaluation of the OCD/ API Model. Final Report, API Pub. 4461, API, Washington, D.C. (1988).Google Scholar
- Hanna, S.R., L.L. Schulman, R.J. Paine, J.E. Pleim, and M. Baer, Development and Evaluation of the Offshore and Coastal Dispersion Model. JAPCA, 35, 1039–1047 (1985).Google Scholar
- Lyons, W.A., Lectures on Air Pollution and Environmental Impact Analysis. (D. Haugen ed). AMS, Boston, 136–208 (1975).Google Scholar
- Turner, D., Workbook of Atmospheric Dispersion Estimates. Office of Air Programs Publ. No. AP-26. U.S. EPA, Research Triangle Park, NC (1969).Google Scholar