http://dotearth.blogs.nytimes.com/2010/03/05/the-heat-over-bubbling-arctic-methane/
"there is no evidence (yet) that what is happening is fundamentally new or destabilizing" On Mar 5, 10:11 pm, John Nissen <[email protected]> wrote: > http://www.worldchanging.com/archives/011011.htmlMethane Melt: The Most > Important Story You Don't FollowAlex Steffen, 5 Mar 10 > We've written before about the danger that climate change will lead to the > thawing and release of methane frozen on the ocean floor, and indeed the > worrisome news that some scientists were observingpatches of Arctic sea > foaming with gas bubbles from "methane chimneys" rising from the sea floor. > Now, researchers in Alaska have founda similar process underway: > Natalia Shakhova, a scientist at the university and a leader of the study, > said it was too soon to say whether the findings suggest that a dangerous > release of methane looms. In a telephone news conference, she said > researchers were only beginning to track the movement of this methane into > the atmosphere as the undersea permafrost that traps it degrades. > But climate experts familiar with the new research reported in Friday’s issue > of the journal Science that even though it does not suggest imminent climate > catastrophe, it is important because of methane’s role as a greenhouse gas. > Although carbon dioxide is far more abundant and persistent in the > atmosphere, ton for ton atmospheric methane traps at least 25 times as much > heat. > Until recently, undersea permafrost has been little studied, but work so far > shows it is already sending surprising amounts of methane into the > atmosphere, Dr. Shakhova and other researchers are finding. > Last year, scientists from Britain and Germany reported that they had > detected plumes of methane rising from the Arctic seabed in the West > Spitsbergen area, north of Scandinavia. At the time, they said they had begun > their work hoping to gain data to predict future emissions and had not > expected to find evidence that the process was under way. > It is “indispensable” to keep track of methane in the region, Martin Heimann > of the Max Planck Institute in Germany said in a commentary accompanying the > Science report. So far, Dr. Heimann wrote, methane contributions from Arctic > permafrost have been “negligible.” He added: “But will this persist into the > future under sustained warming trends? We do not know.” > In an e-mail message, Euan G. Nisbet of the University of London, an expert > on atmospheric methane, said the situation “needs to be watched carefully.” > Atmospheric concentrations of methane have more than doubled since > pre-industrial times, Dr. Heimann wrote. Most of it comes from human > activities including energy production, cattle raising and the cultivation of > rice. But about 40 percent is natural, including the decomposition of organic > materials in wetlands and frozen wetlands like permafrost. > Dr. Shakhova said that permafrost in the East Siberian Arctic Shelf, peat > land that flooded as sea levels rose after the last ice age, is degrading in > part because runoff from rivers that feed the Arctic Ocean is warmer than in > the past. > She estimated that annual methane emissions from the East Siberian Arctic > Shelf total about seven teragrams. (A teragram is 1.1 million tons.) By some > estimates, global methane emissions total about 500 teragrams a year. > Dr. Shakhova said that undersea methane ordinarily undergoes oxidation as it > rises to the surface, where it is released as carbon dioxide. But because > water over the shelf is at most about 50 meters deep, she said, the gas > bubbles to the surface there as methane. As a result, she said, atmospheric > levels of methane over the Arctic are 1.85 parts per million, almost three > times as high as the global average of 0.6 or 0.7 parts per million. > Concentrations over the shelf are 2 parts per million or higher. > A huge release of one-frozen methane is (potentially) almost the definition > of afeedback loop, perhaps even a tipping point into runaway climate change. > Luckily, we're not there yet. Scientists have been very clear to say that > while these field observations are surprising and disturbing, they do not yet > indicate a catastrophe. We need to wait for more data to figure out if it's > time to panic yet. > In the meantime, we need to focus even more strongly on four solution spaces: > 1) Getting to azero net emissionseconomy as quickly as possible. It's very > clear now that we can do this at a net gain for society, with more (and more > wide-spread) prosperity for most people, and that it's largely the opposition > of entrenched interests that's preventing us from making huge strides > forward: this needs to change. > 2) Implementingclimate-adaptive ecological restoration, safeguardingecosystem > services and researchingsoil carbon sequestrationand other practices that > have multiple benefits while pulling greenhouse gasses from the air. We need > to be helping the planet's natural systems heal towards resilience as much as > we possibly can. > 3) Engaging ina stronger and more realistic debate about geoengineering, its > limits and its politics, especially since news of potential tipping points > always accelerates calls for geoengineering research, even deployment. > Geoengineering's main use in the climate debate at the moment is as > apropaganda tool by those seeking to stall action on emissions reduction; > that doesn't mean that we don't need to discuss what mega-scale answers might > be possible should we find tipping points sliding past more quickly than we > feared. > 4)Building psychological resiliencein the face of huge and alarming planetary > changes. News like this is disturbing. We need to find ways, as a culture, as > communities and as individuals, to understand disturbing changes without > losing our balance. Psychologically wrecked people are no good to themselves, > others or the planet. We need to promote the capacity to be healthy and happy > despite monumental challenges. -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en.
