Plume vs Cloud
With all of the "he said, she said" and finger pointing going on in the media surrounding the BP blowout, MSNBC has a very good slide show describing the physics behind what happens to oil after it's spilled into a body of water. Perhaps this will help explain why BP claims no large scale "plumes" of oil beneath the surface, while NOAA claims to have found evidence of large "clouds" of low hydrocarbon concentrations (0.5 parts per million) extending hundreds of miles from the well site, as reported in this LA Times article.
I certainly don't want to make light of this environmental disaster, and I don't know the long term effects of these concentrations on marine life, but by my quick calculations 0.5 ppm is equivalent to 2-3 tablespoons dissolved in a 20,000 gal swimming pool. If you wear sunscreen when you swim, you may be swimming in one of these hydrocarbon clouds without realizing it. Hopefully people can understand why BP executives may not be thinking of these areas of low concentration as they are tasked with cleaning up millions of gallons of heavily concentrated oil floating towards the area beaches.
I don't think the existence of these areas of low hydrocarbon concentrations (be it a "plume" or a "cloud") should be all that surprising given the fact BP has been using chemical dispersants for some time now. These dispersants are designed to breakup the areas of high oil concentration into lower concentrations that can then disperse into the surrounding water. There are numerous questions that need to be answered about what caused the blowout and why it wasn't controlled, but the debate about the existence of these "oil plumes" seems to me can be addressed by everyone agreeing on a definition of a "plume."
BP reports they are now recovering 15,000 BOPD (barrels of oil per day) and hope to increase this recovery by utilizing the lines that were installed into the BOP (blowout preventer) for the failed "top kill" operation. This is certainly an improvement and a step in the right direction, but realistically the only thing that is going to stop this well from flowing are the two relief wells currently being drilled, and they are still a month or two away, or if something unforeseen happens down hole at the source.
