Scientists Hope BP Oil Spill Offers Clues about Global Warming

While everyone else worries about the toxicity of the oil, the physics of plume dispersion, and the costs to wildlife and workers across the gulf, one crew of scientists see a once-in-a-lifetime opportunity. The obvious ethical restrictions to releasing large amounts of methane (which contributes 25 times more greenhouse effect than carbon dioxide) into the ocean has complicated study of how seepage of natural gas at the ocean floor contributes to global warming. Their investigation could also help answer one of the questions everybody else is asking: just how much oil has been released?

John Kessler, of the Department of Oceanography at Texas A&M University in

Assistance Professor, Oceanography

College Station, has dedicated his life to understanding the effect of natural methane seepage on global climate. The question is spurred by evidence that a large natural gas release might have triggered a spike in the earth's temperature about 55 million years ago. Deposits from that era show a significant increase in the proportion of C-12 (light) carbon relative to C-13 (heavy) carbon. Oceanic methane releases could account for the magnitude of C-12, while terrestrial sources seem unlikely: "To cause this type of global isotopic shift, you'd have to take all terrestrial plants and burn them into carbon dioxide," Kessler says in the June 11 edition of Science.

Oceanographer David Valentine of the University of California, Santa Barbara, will join Kessler on the cruise. Valentine believes the methane measurements planned for these experiments will be more reliable than video or satellite images for calculating the scope of this disaster. Methane, unlike oil, can dissolve in and mix with the water, distributing more evenly than the oil, which is suspended in the water in droplets or gobs.

According to BP estimates, approximately 40% of the mass spewing from the deepwater reservoir consists of methane, much of which reacts with water in the cool, pressurized depths to form crystals similar to ice -- the "ice crystals" that have complicated efforts to contain the release. This methane plume is not enough to affect modern climate, according to Kessler, but the BP oil disaster presents a unique laboratory for his research.

The team will attempt to understand the fate and distribution of the methane released in the BP oil gusher. Is 1% released into the atmosphere, or 90%? This information will certainly interest others studying the plumes' effects. For example, if more methane remains tied up in the ocean depths, the microbial buffet will contribute more seriously to oxygen depletion, and a corresponding loss of biodiversity. The team will return from the research cruise around 20 June with their initial data.

Source : treehugger