Lawrence Livermore National Laboratory

During real-world emergencies, initial model predictions can have a high degree of uncertainty due to limited knowledge regarding the release and the complexity of real-world conditions. Field measurements are used to validate and/or improve model predictions. Data-model analysis techniques provide a powerful approach for reducing model uncertainties and developing increasingly accurate assessments of the health and environmental consequences of hazardous releases.

As part of its standard operational response procedures, NARAC works closely with deployed field teams. Initial model predictions based on available source location and emission information are used to guide aerial and ground monitoring surveys. As field data are collected, NARAC conducts graphical and statistical comparisons of model predictions and measurement data in order to estimate unknown source terms and refine its simulations. Updated model products then are provided to field teams, emergency responders, and decision makers and the cycle continues until the impacts of the release are characterized.