Model sensitivity analysis in environmental emergency management: a case study in oil spill modeling

When simulation models are used as decision support systems in environmental emergency response, it is important to know the confidence of simulation results generated by a model. The Hazardous Material Response Division (HAZMAT) at NOAA uses the oil weathering software package named ´Automated Data Inquiry for Oil Spills´ (ADIOS) to investigate the oil weathering process. This model combines a database of the physical and chemical properties of oils with a simulation model for computing the mass losses, density, viscosity and water content of an oil spill due to evaporation, dispersion and emulsification. The sensitivity analysis of the ADIOS model with respect to environmental conditions and oil physical parameters is discussed in this paper. To perform the sensitivity analysis, the Object-Oriented Modeling System was used, together with the Sensitivity Analysis Laboratory, both being developed at NOAA. Preliminary results of the sensitivity analysis of the evaporation process are presented. According to these preliminary results, it is expected that it will be possible to provide a taxonomy of oils with respect to the reliability of the results generated by the ADIOS model. A sensitivity analysis of the complete ADIOS model is in progress.