The Naval Research Laboratory was also able to secure 48 hours of meteorological reconstruction with the MM5 mesoscale model from the National Center for Atmospheric Research. These results were generally consistent with both COAMPS and OMEGA, although the three models predicted somewhat different areas of agent coverage.
Based on the initial presentations to the Panel, and the additional analyses performed and presented, the Panel has the following recommendations for improving the Khamisiyah analysis and for performing such analyses in the future.
Because there are uncertainties in the source term and the meteorology, and differences in the models used in the analysis, there can be no single definitive reconstruction of this event; the differences in possible outcomes are such that it will not be possible to specify the dosage received at a given location. The best that can be done is to provide a range of possible dosages. If one is willing to impose a prior probability distribution on the input conditions-for example, assuming all are equally likely then a distribution of outputs can be derived.
Estimating the Source Term
Among the most important facets of the source term are:
Because there are little or no existing data regarding the release of chemical agent under the conditions that prevailed at Khamisiyah, it may be possible to improve the estimates of some of these factors through field and laboratory tests; however, it must be recognized that a certain degree of uncertainty will always remain with regard to source term matters.