WHERE'D ALL THAT AWL GO?

One of Ned's loyal and prescient followers has asked Ned to describe where all the oil went in the GOM, since MSM reports indicate that very little of it is found on the beaches or in the wetlands at present, and the surface slick has all but dissipated. It remains to be seen how much oil is present in "plumes". Ned will try to tackle this as dispassionately as possible.
First, crude oil is very volatile and it is lighter than water. Much of it will evaporate if just left alone at the surface, because it is made of many different hydrocarbons with varying vapor pressures. But the evaporation points also depend on water and air temperatures. Here is where the GOM has an advantage over Prince William Sound: the Gulf is very warm, with surface temps approaching 90 during the summer max, which we have now. Air temps, too. This helps the stuff to evaporate quickly and form Volatile Organic Compounds, or VOCs, the same stuff that forms smog. It in turn gets broken down by sunlight.
The heavier stuff still floats, but as it concentrates it forms asphalt-like clumps which are easy to pick up. Next, the dispersants have made it easier for the GOM microbe communities to break up the oil and eat it. These little buggers are everywhere, and they flourish because the GOM is the site of thousands of natural "seeps" of oil and gas. The bacteria break down the hydrocarbons for food.
Some of the oil was skimmed at the surface, filtered out of the seawater and disposed of--don't ask Ned where, probably in a landfill, or burned.
Some of the oil apparently was rendered so small in size that it floated below the surface in the so-called "plumes." Now NOAA says the concentrations of oil in the water in these plumes is on the order of 500 ppb, or about a teaspoon in a swimming pool.
Trouble is, we don;t know what background hydrocarbon content in the GOM is. The good thing is, where the plumes are, at depths of several thousand feet, is where very few animals live. Most of them live in the surface 100 meters or on the bottom, so they are unlikely to be severely affected.
The biggest remaining problem is probably oil in wetlands, but even there, bugs eat it, and plants rapidly can re-grow parts affected by the oil. Now if we can get the poor pelicans cleaned "off" Ned will sleep more soundly, but, even here, more pelicans are killed by shrimpers that have been killed by the oil.
Hope that helps.