High levels of the gas in the atmosphere could speed up climate change
Scientists are worried about methane bubbling to the surface of the Arctic Ocean. The thawing of the Arctic as temperatures rise is releasing methane in the seabed. Scientists say high levels of the gas in the atmosphere could speed up climate change.
According to the The New York Times, scientists have recently been investigating areas of increasingly ice-free shallows off Russia’s Siberian coast that are producing millions of tons of methane gas ever year. The concern over the observation is that methane has at least 20 times the heat-trapping properties of the greenhouse gas carbon dioxide.
Daily Mail reports that methane concentrations in the Arctic averages about 1.85 parts per million, the highest in 400,000 years, and concentrations in the East Siberian Arctic Shelf are even higher. In deep water methane gas oxidizes into carbon dioxide, but in shallow waters of the East Siberian Arctic Shelf, methane does not have enough time to oxidize, so it escapes into the air contributing to greenhouse gas concentration. Increased methane production from thawing sea-bed stores of the gas could accelerate global warming.
Scientists want to find out whether this is the onset of a process with potentially disastrous consequences to the global climate or a longstanding process that is only being observed for the first time. According to Igor Semiletov of the Russian Academy of Science in an interview with UK’s Independent, the plumes of methane gas are causing environmental scientists great worry.
Semiletov told the Independent:
“Earlier we found torch-like structures like this but they were only tens of meters in diameter. This is the first time that we’ve found continuous, powerful and impressive seeping structures, more than 1,000 meters in diameter. It’s amazing.”
Semiletov says they estimate that there could be thousands of the plumes over an area extending from the Russian mainland to the East Siberian Arctic Shelf:
“In a very small area, less than 10,000 square miles, we have counted more than 100 fountains, or torch-like structures, bubbling through the water column and injected directly into the atmosphere from the seabed. We carried out checks at about 115 stationary points and discovered methane fields of a fantastic scale – I think on a scale not seen before. Some plumes were a kilometer or more wide and the emissions went directly into the atmosphere – the concentration was a hundred times higher than normal.”
Other scientists are saying that the alarm being raised is unjustified. A paper published in the Journal of Geophysical Research says that the gas emissions are not recent but are part of a thawing process that began 8,000 years ago. According to The New York Times, a summary of the same paper in the American Geophysical Union on the “methane time bomb,” said:
“…roughly 1 meter of the subsurface permafrost thawed in the past 25 years, adding to the 25 meters of already thawed soil. Forecasting the expected future permafrost thaw, the authors found that even under the most extreme climatic scenario tested this thawed soil growth will not exceed 10 meters by 2100 or 50 meters by the turn of the next millennium. The authors note that the bulk of the methane stores in the east Siberian shelf are trapped roughly 200 meters below the seafloor…”
Other scientists who have been tracking methane in the atmosphere say they have seen no significant surge in levels of methane than can be blamed on the Arctic sea-bed emissions. Ed Dlugokencky, a researcher tracking methane trends in the atmosphere, says:
“Based on what we see in the atmosphere, there is no evidence of substantial increases in methane emissions from the Arctic in the past 20 years.”
Source: Digital Journal
