Where is all the oil? Nearly two weeks after BP finally capped the biggest oil spill in U.S. history, the oil slicks that once spread across thousands of miles of the Gulf of Mexico have largely disappeared. Nor has much oil washed up on the sandy beaches and marshes along the Louisiana coast. And the small cleanup army in the Gulf has only managed to skim up a tiny fraction of the millions of gallons of oil spilled in the 100 days since the Deepwater Horizon rig went up in flames.
So where did the oil go? "Some of the oil evaporates," explains Edward Bouwer, professor of environmental engineering at Johns Hopkins University. That’s especially true for the more toxic components of oil, which tend to be very volatile, he says. Jeffrey W. Short, a scientist with the environmental group Oceana, told the New York Times that as much as 40 percent of the oil might have evaporated when it reached the surface. High winds from two recent storms may have speeded the evaporation process.
[Photos: Latest from the Gulf oil spill]
[Related: 100 days of oil: Gulf life changed for good]
Although there were more than 4,000 boats involved in the skimming operations, those cleanup crews may have only picked up a small percentage of the oil so far. That’s not unusual; in previous oil spills, crews could only scoop up a small amount of oil. "It’s very unusual to get more than 1 or 2 percent," says Cornell University ecologist Richard Howarth, who worked on the Exxon Valdez spill. Skimming operations will continue in the Gulf for several weeks.
Some of the oil has sunk into the sediments on the ocean floor. Researchers say that’s where the spill could do the most damage. But according to a report in Wednesday’s New York Times, "federal scientists [have determined] the oil [is] primarily sitting in the water column and not on the sea floor."
Perhaps the most important cause of the oil’s disappearance, some researchers suspect, is that the oil has been devoured by microbes. The lesson from past spills is that the lion’s share of the cleanup work is done by nature in the form of oil-eating bacteria and fungi. The microbes break down the hydrocarbons in oil to use as fuel to grow and reproduce. A bit of oil in the water is like a feeding frenzy, causing microbial populations to grow exponentially.
A year is short when your livelihood isn't that of nor dependent on that of a fisherman in Prince William Sound.
