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].
An extinct ancestor of the great white 
