Testing and Validating Against Historic Spills

To validate the predictive capability of ERA Acute, a study was carried out using data from two well-studied historic oil spills, the Exxon Valdez Oil Spill (EVOS) and the Deepwater Horizon Oil Spill (DHOS) incidents. Results from the case studies with ERA Acute were compared to the impact estimates and recovery observations that have been reported in the extensive research following the two incidents. Resource data relevant for each of the two incidents were reconstructed within the analysis area. Performance boundaries were set up for evaluating the ERA Acute results, based on the ranges of the impact and recovery estimates reported in the post-spill assessments. Validation of an oil spill ERA model against post-spill assessments of historic spills is a challenging exercise due to scientific limitations of both. ERA Acute performed satisfactorily compared to the performance boundaries and the study gave useful insight into the predictive capabilities of ERA Acute. The results from the study were used to evaluate between two different impact models and to increase the individual vulnerability of cetaceans.