Alarming but preliminary reports of methane gas bubbling up from the Arctic Ocean have raised the specter of precipitous global warming in the minds of some climate scientists.

While aboard a research ship sailing off the coast of Siberia, scientists observed high levels of methane in the water, and then spotted several areas where the gas bubbles were fizzing up from the ocean floor, which contains vast amounts of frozen methane. That was enough to ring the alarm bells: Methane is about 20 times more powerful as a greenhouse gas than carbon dioxide and many scientists fear that its release could accelerate global warming in a giant positive feedback where more atmospheric methane causes higher temperatures, leading to further permafrost melting and the release of yet more methane [The Independent].

While the news seems disquieting, some researchers are expressing some skepticism about the findings, which haven’t yet been published in a peer-reviewed journal. The initial word from a heap of scientists who are focused on sub-sea methane deposits, including a group that videotaped big burps of methane bubbles off Santa Barbara, Calif., a few years ago, is a note of caution about overinterpreting the Arctic bubbling and high gas concentrations as something a) new or b) driven by human-caused global warming [The New York Times, Dot Earth blog].

Reporting from the boat, researcher Orjan Gustafsson said his team found some ocean areas where the methane levels were 100 times higher than average, and also observed areas of sea foaming with gas bubbling up through “methane chimneys” rising from the sea floor. They believe that the sub-sea layer of permafrost, which has acted like a “lid” to prevent the gas from escaping, has melted away to allow methane to rise from underground deposits formed before the last ice age [The Independent].

A massive release of methane from the world’s oceans figures into an extravagant global warming doomsday scenario, as a few researchers have suggested that Earth’s temperature could reach a tipping point at which massive amounts of methane thaw out and are released into the atmosphere. Paleoclimatologists have suggested that underground stores of methane have in the past been responsible for rapid rises in global temperatures, changes in the climate and even extinction of species [Telegraph]. But the science has yet to be settled on many of these points.

Ocean methane isn’t just a component in disaster scenarios, though, it’s also a potential source of energy. Learn who wants to mine it in the DISCOVER article “If Life Gives You Methane, Make Methane Energy.”

Image: flickr/nick_russill

Related Post: A Monstrous Methane Belch Once Warmed the Earth

September 24th, 2008 5:11 PM Tags: global warming, methane, ocean
by Eliza Strickland in Environment | 5 comments | RSS feed | Trackback >