It’s official: After a computer model on Monday showed that oil in the Gulf of Mexico had probably entered the loop current, which flows into the Florida Keys and up the Eastern U.S. coast, satellite imagery confirms that this is the case. Analyzing satellite imagery from NASA, blogger Jeff Masters writes that “a substantial tongue of oil has moved southeast from the Deepwater Horizon oil spill and entered the Gulf of Mexico's Loop Current.” Masters says that, once the oil enters the current, it will probably take 10 to 20 days for it to hit the Keys, though it could be as few as four or five days. This means it’s likely that the Keys will be the first beaches in Florida to see the oil.
This study implies that the greatest risk of land impacts by surface oil caught in the Loop Current is along the ocean side of the Florida Keys, and along the coast of Southeast Florida from Miami to West Palm Beach. Eddies breaking away from the Gulf Stream would also likely bring oil to northwest Cuba, the western Bahamas, and the U.S. East Coast as far north as Cape Hatteras, North Carolina, though at lesser concentrations.
This is a joint effort of the Ocean Circulation Group and the Optical Oceanography Laboratory at College of Marine Science, University of South Florida to track/predict the Deepwater Horizon oil spill in the Gulf of Mexico using simulated drifters/particles. Drifter trajectories were calculated based on the daily surface currents from the HYCOM + NCODA Global Analysis (data assimilative numerical ocean model hindcast & forecast). Virtual particles were released from the sunken rig site every three hours, assuming continual oil spill from the well. The initial locations of the drifters were inferred from the latest satellite sensed oil slick patches. The subsequent movements of the virtual particles were estimated by the model, not by observations. It must be recognized that all forecast models have errors that grow with time for a variety of reasons. This is one reason why it is important to consider comparative analyses from several different models. The particles (difters) are shown as black dots, and their trajectries in magenta. Macondo well is designated by the red circle. Sea surface temperature (color contours, units in deg C) was superimposed with the surface current vectors to indicate the surface ocean circulation. The velocity data were subsampled every the third grid points in both east and north directions for better visulization. Questions or comments, please contact Prof. Robert H. Weisberg or Dr. Yonggang Liu.
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