Are ocean currents likely to carry spilled oil to Atlantic?

In early June, 2010 many news organizations reported that the answer was yes.

Are ocean currents likely to carry oil from the BP spill out of the Gulf of Mexico and into the Atlantic? In early June, 2010 many news organizations reported that the answer was yes. They based their reports on a video from the National Center for Atmospheric Research, or NCAR – a computer simulation showing movement from the site of the BP oil spill in the Gulf of Mexico up the eastern seaboard of the U.S. and into the open ocean. But NCAR scientist Synte Peacock – who helped create the video – told EarthSky that it wasn’t depicting the movement of oil. It was one of six scenarios developed by NCAR showing the movement of a dye on ocean currents.

Synte Peacock: We didn’t try to simulate oil, so we put in a dye which is like a food coloring. It has no physical resemblance to crude oil.

Peacock said that – within 6 months – a dye would travel to the Atlantic Ocean. Oil behaves differently for various reasons.

Synte Peacock: But we still think it’s very likely that oil will get into the Atlantic.

If it does, she said, people shouldn’t expect oil to coat Atlantic beaches and wildlife. That’s because, over the months it would take to travel there – if it does travel there – some oil will evaporate, be eaten by microbes, and become diluted in sea water. EarthSky also spoke with oceanographer Breck Owens at Woods Hole Oceanographic Institution, whose team has released an underwater robot to directly measure currents in and around the oil spill. He said right now Gulf currents are too unpredictable to make accurate forecasts of where the oil will travel. Dr. Peacock added that the NCAR video was based on studies done previous to the oil spill.

Synte Peacock: We’ve done a lot of dye releases, these scientific experiments, for completely different reasons. So we had this model that was up and ready to go at very, very short notice. So as oil spill became a bigger and bigger problem, and started penetrating into the public awareness, we realized that we could very easily do this scenario, to explore possible pathways.

She said the video does not attempt to simulate how oil will act in the Gulf, because there are too many variables to make an accurate prediction.

Synte Peacock: We can’t do predictions, We can’t do forecasts here. But we can do something which is complimentary to that, which is to say, ‘Here’s a set of possible pathways that a dye released at point of the oil spill might take, and explore a whole range of possibilities to see if there are any scenarios where oil stays in the Gulf.’

Dr. Peacock said in all the possible scenarios and simulations that were tested, oil from the oil spill traveled outside of the Gulf within 6 months. But she added that it’s still unclear if or how the oil will affect beaches on the Atlantic Coast. That eventual outcome is partially dependent on local weather around the time the oil reaches a beach. She emphasized that the oil will look different, if and when it does indeed reach the Atlantic.

Synte Peacock: What you see coming into the Atlantic will not necessarily be a slick, it might be tarballs, it might very, very well mixed in the upper tens of feet of ocean, so it’s very, very hard to see.

Breck Owens of Woods Hole said that the states bordering the Gulf are going to be hardest hit by the oil spill, despite the future direction of the oil spill.

Breck Owens: The point is if we have limited resources, we need to spend our resources on the Gulf. That’s the bottom line. The major problem is going to be in Louisiana, Mississippi, Alabama, and Florida.

Owens, along with many colleagues, are deploying scientific instruments into the Gulf in order to monitor the oil and how the spill interacts with the various currents and eddies that could influence how it moves through the ocean. Owens said that the effort is in its early stages, and it will be a while until any predictions can be made.

Lindsay Patterson