Global warming alarmists have long held that as the globe warms it will melt the permafrost in the Arctic and cause release of the powerful greenhouse gas, methane. New research from Princeton University, however, claims that methane-hungry bacteria in the soil will absorb methane and that ability will increase with rising temperature.
A Princeton press release reports on a new paper published in The ISME Journal: “An active atmospheric methane sink in high Arctic mineral cryosols.” (Paper is pay-walled)
According to Princeton:
“The researchers found that Arctic soils containing low carbon content — which make up 87 percent of the soil in permafrost regions globally — not only remove methane from the atmosphere, but also become more efficient as temperatures increase. During a three-year period, a carbon-poor site on Axel Heiberg Island in Canada’s Arctic region consistently took up more methane as the ground temperature rose from 0 to 18 degrees Celsius (32 to 64.4 degrees Fahrenheit). The researchers project that should Arctic temperatures rise by 5 to 15 degrees Celsius over the next 100 years, the methane-absorbing capacity of “carbon-poor” soil could increase by five to 30 times.”
“The researchers found that this ability stems from an as-yet unknown species of bacteria in carbon-poor Arctic soil that consume methane in the atmosphere. The bacteria are related to a bacterial group known as Upland Soil Cluster Alpha, the dominant methane-consuming bacteria in carbon-poor Arctic soil. The bacteria the researchers studied remove the carbon from methane to produce methanol, a simple alcohol the bacteria process immediately. The carbon is used for growth or respiration, meaning that it either remains in bacterial cells or is released as carbon dioxide.”
About two years ago, there was another Arctic methane scare that dealt with methane hydrates which occur in marine sediments and crop out on the ocean floor where the pressure is sufficiently high and the temperature is sufficiently low. Methane has been percolating from marine sediments for hundreds of years, at least, and has not suddenly appeared due to global warming.
Geophysicist Judith Curry notes on her blog: “Most scientists who have specific knowledge in the area say a rapid release of methane due to warming is highly unlikely…even if the ocean warms, most of the methane released by thawing permafrost could stay in the seabed or dissolve in seawater.” For more on this aspect, see my Wryheat post: “The Great Arctic Methane Scare.”
A major tectonic event, however, could possibly release large quantities of methane from methane hydrates as has been postulated for the Paleocene-Eocene Thermal Maximum 55 million years ago. (See my ADI article: Geologic History: PETM when it really got hot )