The Deepwater Horizon explosion reopened debate on the role of synoptic weather features versus ocean currents in transporting oil spills. Lagrangian models generally assume oil concentrations travel largely proportional (80-100%) to ocean currents’ speed and direction, plus an additional 3% contribution from surface winds, diffused with each time step. However, cyclones are known to highly perturb water pollutants with positive and negative results. A midlatitude cyclone expanded the Exxon Valdez oil spill over a large region, while in contrast Hurricane Henri (1979), in combination with a non-tropical low, cleansed the oil-polluted south Texas beaches (Gundlach et al. 1981).

We identified the late June to early July timeline as a period of interest since oil briefly impacted the Rigolets, Lake Borgne, and western Mississippi coast, and represented the innermost penetration of oil pollution east of the Mississippi River. An important component to understanding the oil transport is to distinguish the influences behind this apex moment. An oil spill simulation was conducted for the period 20 June to 10 July 2010 to understand this inland transport. Meteorology and ocean data, as well as synoptic maps also facilitated this analysis. The results of this analysis, as well as validation of numerical model wind analysis, are presented in this report. We also briefly discuss hydrology modeling software designed to predict the movement of oil pollution in the event of a hurricane landfall in the oil spill region at the end of this report.