Gulf spill oil driven by complex ocean currents and eddies
The BP oil spill in the Gulf of Mexico is far different than the Exxon Valdez spill in Alaska. The complex marine environment has currents and eddies that could carry the oil anywhere in the Gulf.
Oil boom stretches along empty beaches, tar balls have washed ashore along the Alabama and Mississippi coasts, and a swirling, oily sheen covers at least 2,500 square miles of the sea surface in the Gulf of Mexico.Skip to next paragraph
So far, currents, winds, and a plume of fresh water flowing into the Gulf from the Mississippi River have acted in concert to hold at bay the oil spewing from a damaged well head 5,000 feet below the sea surface some 40 miles off the Louisiana coast.
In anticipation of the oil's arrival, some 13,000 people stand ready to combat the spill if it approaches shore, according to the Obama administration. More than a million feet of boom has been deployed. More than half a million gallons of dispersants has been applied.
But the differences between the two events are significant, cautions Michelle Wood, a marine biologist who recently became head of the ocean chemistry division of the National Oceanic and Atmospheric Administration's Atlantic and Oceanographic and Meteorological Laboratory in Miami. Not the least of those differences is the seascape into which the oil is flowing.
Gulf spill unlike Exxon Valdez
The Exxon Valdez spill involved a large, single, intense pulse of oil into Prince William Sound – "a shallow, near-shore environment with a rocky coast," she explains. The heavy crude had lots to cling to as it came ashore. In the Gulf, "spill" is a so-far continuous infusion of a lighter grade oil, which at least initially forms a foamy mousse rather than tarry blobs. And so far, the oil has remained far at sea.
The apparent gap between preparations for the oil's arrival along the Gulf Coast and its behavior so far testify to the complex marine environment the oil enters as it spews from the broken well head, researchers say.
The system is chaotic enough that given enough time, say 90 days, oil in some form could wind up anywhere from the Mexican Coast to Palm Beach, research suggests.