August 25, 2010
- A d v e r t i s e m e n t
The NOAA-Princeton team’s computer analyses also suggest why deep-sea plumes can hang around for months or longer. Currents at great depths, two-thirds of a mile below the surface, move far more slowly than those near shorelines or the surface. So don’t expect deep hydrocarbon plumes to swoosh rapidly out into the Atlantic, Hallberg says. They’re more likely to slosh back and forth with the tides and in response to local eddies. Indeed, his group’s modeling data suggest “they will stay very much confined — within, say, about 100 kilometers of the spill site.”
He predicts that if the Woods Hole team resurveyed the plume site three to nine months from now, it would likely still find much of the oil there. By then, microbes may be dining on the hydrocarbons in earnest, locally drawing down oxygen levels. In the deep ocean, Hallberg notes, oxygen isn’t replenished quickly, so any losses tend to accumulate over time. “According to our simulations, these [very low oxygen] areas will be peaking in October,” he says, potentially making some portions of the northern Gulf inhospitable to sea life.