Contrasting the use of single-realization versus ensemble-average atmospheric dispersion solutions for chemical and biological defense analyses

Because it is not feasible to evaluate these systems with open-air testing alone, researchers rely on numerical models to supplement the defense-system analysis process. These numerical models traditionally describe the statistical properties of CB-agent atmospheric transport and dispersion (AT&D).

While the statistical representation of AT&D is appropriate to use in some CB defense analyses, it is not appropriate to use this class of dispersion model for all such analyses. Many of these defense-system analyses require AT&D models that are capable of simulating dispersion properties with very short time-averaging periods that more closely emulate a "single realization" of a contaminant or CB agent dispersing in a turbulent atmosphere.