Looking for the oil ? NOAA says it's mostly gone

video : Allen, 'High confidence' no more oil will leak

From Richard Black, BBC News

While listening to the latest briefing on the Gulf of Mexico oil leak, I've been wondering whether the questions being answered are the right ones.

The key factoid presented by the National Oceanic and Atmospheric Administration (Noaa) is that about three-quarters of the 4.9 million barrels that entered the Gulf waters has been dealt with.

About one quarter has naturally dissolved or evaporated, and another quarter was captured at source or skimmed or burned. Those portions have effectively been eliminated from the sea.

A further quarter has been dispersed, either naturally or chemically - leaving the remaining quarter that, in Noaa's words...

"...is either on or just below the surface as light sheen and weathered tar balls, has washed ashore or been collected from the shore, or is buried in sand and sediments."
In the early days, the scale of the leak became a vital statistic, central to questions both about the incident's politics ("Is BP telling the truth? Is the government?") and about the eventual ecological impact.

Daily we followed maps of where the slick was blown; and the revelations of underwater oil plumes, and the succession of new estimates projecting successively higher flow rates, made for compelling reading.

But at what appears to be the tail end of the affair, arguably size matters less than ever.

Just as with fishing or anything else you do in the marine world, the issue isn't only "how much?" but "where?"

Heavy trawls dragged over grey, boring sea floor will leave behind grey, boring sea floor. Use the same gear on deepwater coral, and you wreak ecological carnage.

Likewise Deepwater Horizon. Oil flecked across the wide Gulf seas will have far less impact on wildlife or fish or anything else than if blobs of the stuff happen to congregate in a marsh vital for a threatened species of breeding bird, or an aggregation of spawning bluefin tuna.

Along some beaches, people are still rescuing oil-soaked pelicans; on others, they're already toasting themselves in the Gulf sun, as though the oil never happened.

At present, as I discussed in my analysis article on Tuesday, evidence for widespread ecological damage is thin; so we have to presume that as of now, the significant volume of oil that remains (even a quarter of 4.9 milion barrels is still far more than released by the Exxon Valdez) is not hitting enough of those key zones to be having a major impact.

The other question posed by the Noaa analysis is a "who?" question, as in "who looks good now?"

Away from the oil-washed segments of Gulf coast where hydrocarbons pervade the air, arguably the strongest aroma generated by this whole affair has been one of political fragrance.

It's been said that US politicians could heavily and publicly blame BP because of what the B stands for. That's not to excuse anything the company has done, and it has admitted culpability in a number of ways; but it's hard to imagine good ol' Southern boys being quite so disparaging if the oil company in question had been of good ol' Southern origin.

Shifting everything onto the company's shoulders was also a way of distracting attention from anything the Bush or Obama administrations, or indeed the Houses of Congress, could have done differently - such as insisting on a regulatory regime with more stringent safeguards.

With mid-term elections approaching, having a government agency proclaim a kind of victory over the oil now is what you might term a fairly slick piece of business.

Does Noaa's analysis add up? Not everyone thinks so, with Florida State University oceanographer Ian MacDonald saying:

"There's some science here, but mostly it's spin, and it breaks my heart to see them do it... I'm afraid this continues a track record of doubtful information distributed through Noaa."
Perhaps the most doubtful aspect of it, though, is that for ecological purposes it appears simply to be addressing a question that doesn't matter very much.

Links :

• Nature : a scientist at the centre of the spill
• Al.com : despite oil disappearance, scientists say dangers could linger in the Gulf
• NRDC : many questions still unanswered on dispersants following EPA report
• WSJ : Timeline, key developments since the initial explosion