Weathered oil takes on a foamy appearance on Elmers Island, Louisiana. Photograph by Chris Combs, National Geographic

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Weathered oil at Elmers Island, near Grand Isle, Louisiana. The oil is the chunky/foamy brown stuff. This is one of the worst areas near Grand Isle right now.

Weathered oil takes on a foamy appearance on Elmers Island, Louisiana. Photograph by Chris Combs, National Geographic

Hurricanes May Be Good for Gulf Oil Spill, Experts Say

Storms may help disperse slicks, but oil surging inland still a worry.

Part of an ongoing series on the environmental impacts of the Gulf oil spill.

For Louisiana resident Merry Schultz, a trip to her regular vacation spot this year wasn't exactly a day at the beach.

Standing on a long pier at Grand Isle State Park on Tuesday, Schultz surveyed a shoreline littered with crusty tarballs and bordered by water shining silver with crude from the Gulf of Mexico oil spill.

To add insult to injury, low-lying storm clouds darkened a beach pounded by angry waves—calling cards of tropical storm Alex, now Hurricane Alex, roiling out at sea.

"What's sad about this is it's June," Schultz said, sweeping her arm over the scene. Usually at the start of summer, "this would be full of tents and campers."

Although Hurricane Alex is not predicted to directly affect the Gulf oil spill, strong winds and waves have hampered cleanup and containment efforts. Experts are also sounding alarms that Hurricane Alex's storm surge may push oil deeper into already threatened marshland.

Still, there could be a silver lining to the storm clouds: The "extremely active" Atlantic hurricane season predicted for 2010 could help break up and disperse offshore oil, giving a boost to nature's self-cleaning abilities, experts say.

"It's hard to find good news in a hurricane," said Edward Overton, an environmental chemist at Louisiana State University (LSU) in Baton Rouge. "But it's not all death and gloom."

"Eggbeater" Hurricane Winds Can Break Up Oil

Powerful hurricane winds can act like eggbeaters, tearing big pools of oil into smaller globs, which are more palatable to oil-eating microbes, according to Siddhartha Mitra, an organic geochemist at East Carolina University in Greenville, North Carolina.

Though oil-munching bacteria are abundant in the Gulf of Mexico, the organisms can't penetrate solid sheets of oil, and so they chew only on the edges of oil slicks.

Breaking oil into smaller pieces allows the bacteria to attack oil globs from all sides, making the microbes "fat and happy," LSU's Overton said.

"Our environment can really handle oil. It's very acclimated. It might take a year or two, but the bacteria will eat [most of the oil] up very, very quickly," Overton said. (See "Nature Fighting Back Against Gulf Oil Spill.")

More manageable pieces of oil also boost the rate at which dissolved oxygen in seawater can chemically weather the oil, changing the crude's properties. Over time, weathering can reduce the oil's overall toxicity, East Carolina's Mitra said.

Likewise, oil in smaller droplets evaporates faster at the water's surface, LSU's Overton noted.

One of the few known examples of a hurricane helping an oil spill occurred in 1979, said Chris Hebert, lead hurricane forecaster for the private forecasting company ImpactWeather, based in Houston, Texas.

That year winds from Hurricane Henri scoured clean most of the Mexican beaches stained by the Gulf of Mexico's Ixtoc oil spill, Hebert said by email.

But the impacts of hurricanes on oil spills is still poorly understood, noted East Carolina's Mitra, who warned that any predictions are "guesswork" at best.

Hurricane's Negative Impacts on Oil "Far Worse"

Overall, ImpactWeather's Hebert cautioned, "the negative impacts [of a hurricane] would likely be far worse" than its upsides.

For example, just the threat of a hurricane headed directly for the oil spill site would shut down efforts to control the oil still spewing from the damaged Deepwater Horizon wellhead, he said.

LSU's Overton also pointed out that any benefits from hurricanes hold true only for oil "meandering" far offshore. Nearshore oil, which is already creeping into Louisiana's marshes, will likely be pushed farther inland by tide surges, he said.

It's even possible hurricanes could pick up oil and deposit it as rain in areas far from the coast, East Carolina's Mitra said.

Hurricane Alex to Send Oil Splashing Inland?

At one of Grand Isle's fishing harbors, out-of-work shrimper Ronald Theriot said that hurricanes bringing oil farther inland is a "big worry."

The native Grand Isle resident recently saw two large pockets of oil just a few miles offshore, and he predicts storm waves could soon send that oil splashing across the region.

Workers were busy Tuesday trucking in dirt to build levees along the road to the harbor in an attempt to block oily waves whipped up by Hurricane Alex or future storms.

If hurricanes do drive oil inland, "Lord have mercy," Theriot said. "I don't think you can have enough people to clean that mess up."