Storm may help dissolve US Gulf oil mess
Miami (AFP) July 25, 2010
The storm which forced a temporary halt to efforts to permanently seal BP's Gulf of Mexico oil well may help dissolve the millions of gallons of spilled crude sloshing around in the sea, experts say.
Bonnie unexpectedly weakened to tropical depression status when it reached the spill zone on Saturday -- strong enough to kick up waves, but too weak to justify BP keeping away its key drill rig, which it sent back to restart work to permanently "kill" the well.
The storm drenched southern Florida on Friday but lost force as it crossed the peninsula and failed to regain strength over the open water as forecasters had predicted.
But the high waves it stirred could help the process of naturally bio-degrading the spilled oil, said Jane Lubchenco, who heads the National Oceanic and Atmospheric Administration (NOAA).
"We expect that Bonnie should help dissipate and weather the oil that's at the surface, it will spread the surface slick out and thereby lower concentrations," Lubchenco told reporters.
"It's expected to break tar patches and tar mats into smaller tar balls, which means faster weathering and faster natural bio-degradation."
The storm "will also cause more natural dispersion, again lowering the concentration and making it more available to natural bacteria that are in the water," she said.
NOAA experts do not expect much upwelling, or below the surface mixing, because Bonnie is moving so quickly, she said.
The remnants of Bonnie are set to hit Louisiana in the northern Gulf Coast late Saturday or early Sunday, the Miami-based National Hurricane Center said.
Laurent Cherubin, an oceanographer at the University of Miami, said rough seas would likely to help break the oil slicks and make them less traceable and more diluted in the water, but that did not mean the problem was resolved.
"That could be a good visible thing but the threat remains for the environment at the invisible level," Cherubin told AFP.
He noted that microorganisms were still dying and the whole ocean food chain was destroyed at its base.
"Therefore, although the threat could visually disappear, it will increase the threat to small organisms by increasing the contamination due to the breaking in smaller parts of the oil," Cherubin said.
"Although animals would leave because of the storm, their food supply could be strongly depleted," he said.
Peter Ortner, director of the Cooperative Institute for Marine and Atmospheric Studies at the University of Miami, agreed with the assessment.
"Degradation of the oil might be accelerated by enhanced mixing and even re-exposure to oxygen in some areas," he told AFP.
Ortner said that one of the few "significant positive" aspects of the storm is that on the western side of Bonnie's landfall "oil that was nearing the shore will be driven offshore, and beaches and coastlines could well be cleaned up by the heavy rains and offshore directed winds."
Manhar Dhanak, director of the Institute for Ocean and Systems Engineering at Florida Atlantic University, warned however that the surface currents bolstered by winds were likely to shift the near-surface oil closer to the Louisiana coast and spread it over a larger area.
Waves from Bonnie "and associated wave-breaking will cause major amount of mixing and dispersion so that the layer of oil at the surface will get thicker," Dhanak said.
On balance Bonnie is "making things different," Lubchenco said.
"I think there is definitely a positive aspect, but different parts of the shore will see different things," she said. "It depends on where you are. I think the bottom line is it's better than it might have been."
The International Energy Agency estimates that between 2.3 million and 4.5 million barrels of crude are now in the sea as a result of the leak.
The oil spill began after an explosion April 20 on a BP-leased Deepwater Horizon rig. The blast killed 11 workers, and the sinking rig unleashed an oil gusher that has grown into the worst environmental disaster in US history.
BP finally capped the well in mid-July, halting the oil from flowing into the Gulf, but a permanent solution to the leak in the form of relief wells remains weeks away.
Share This Article With Planet Earth
Our Polluted World and Cleaning It Up
Beijing (AFP) July 22, 2010
Chinese authorities battled Thursday to contain an oil spill on the country's northeast coast amid reports it was spreading and as warnings emerged of a heavy long-term environmental impact. The government has mobilised hundreds of fishing boats and other vessels to clean up the spill that occurred in the port city of Dalian, but Greenpeace said many people thrown into the effort were reduce ... read more
|The content herein, unless otherwise known to be public domain, are Copyright 1995-2010 - SpaceDaily. AFP and UPI Wire Stories are copyright Agence France-Presse and United Press International. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by SpaceDaily on any Web page published or hosted by SpaceDaily. Privacy Statement|