April 5, 2010

Laughing Gas From Thawing Ice Affects Climate Change

A study showed on Sunday that thawing permafrost could release laughing gas, which is a contributor to climate change that has been overlooked in the Arctic, according to a recent Reuters report.

The study, which was reported in the journal Nature Geoscience, showed that emissions of nitrous oxide surged under certain conditions from melting permafrost that underlies around 25 percent of land in the Northern Hemisphere.

Emissions of the gas leapt 20 times from thawing wetlands in Zackenberg in eastern Greenland to levels found in tropical forests, which are among the main natural sources of the heat-trapping gas.

"Measurements of nitrous oxide production permafrost samples from five additional wetland sites in the high Arctic indicate that the rates of nitrous oxide production observed in the Zackenberg soils may be in the low range," the study said.

The researchers studied sites in Canada and Svalbard off northern Norway alongside their main focus on Zackenberg.  The releases of the gas would be a small addition to global warming.

Nitrous Oxide is third in line as the most important greenhouse gas from human actives.

The U.N.'s Kyoto Protocol regulates the gas for limiting global warming, which could bring about more sandstorms, floods, heatwaves and rising sea levels.

Nitrous Oxide is produced by human actives like agriculture and use of fossil fuels.  It is brought about naturally from sources in soil and water, such as microbes in wet tropical forests.

The scientists, from Denmark and Norway, said that past studies had assumed carbon dioxide and methane were released by a thaw of permafrost while nitrous oxide stayed locked up

"Thawing and drainage of the soils had little impact on nitrous oxide production," Nature said in a statement of the study led by Bo Elberling of Copenhagen University.

"However, re-saturation of the drained soils with meltwater from the frozen soils -- as would happen following thawing -- increased nitrous oxide production by over 20 times," it said.

"Nearly a third of the nitrous oxide produced in this process escaped into the atmosphere," it added.

Carbon dioxide is the most lethal gas to climate change, followed by methane.


Image Caption: Image Caption: Pictured are lichen and shrub"“covered palsas surrounded by a pond resulting from melting permafrost in a bog near the village of Radisson, Canada. Credit: Serge Payette


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