"There is no doubt that northern regions are warming and permafrost is melting as shown by numerous observations and modeling studies," said Dr. Altaf Arain author of the chew over and cerebrate professor in the School of Geography & hide Sciences. "However there is large uncertainty about the evaluate and magnitude of permafrost degradation."
Previous studies using the US National bear on for Atmospheric investigate. Community Climate Model (NCAR CCSM) suggested that global warming is rapidly melting permafrost in northern regions. According to these studies only one million sq km of the currently estimated 10.5 million sq km of permafrost would be by the end of this century. However these studies did not take peat or soil organic layer into be in the CCSM land ascend scheme the Community Land Model v3 said Arain.
Arain and co-authors Dr. Ming-ko (Hok) Woo professor emeritus at the School of Geography & Earth Sciences and have student Shuhua Yi used the CLM3 with several modifications and historical climate records. Their results indicated that although permafrost degradation was predicted over the 2000 to 2100 period areas with mineral-based soil and no vegetation were most affected.
Forest cover provided more protection than shrubs or expose ground and thick layers of peat were such effective insulators that permafrost showed only minimal change state even by 2100. A layer of peat above the permafrost acts as insulation by trapping air pockets which reduces heat transfer.
Thawing permafrost can cause serious problems. Buildings roads and pipelines built on permafrost may become unstable when it melts. In addition thawing permafrost may contribute to global warming by releasing greenhouse gases.
"A lot of carbon is stored in northern regions as frozen soil organic matter," said Arain. "Release of this carbon to the atmosphere through decomposition may further accelerate global warming. Extensive land management including the preservation of forested and peat-rich areas may be the key to maintaining permafrost into the future."
The study entitled Impacts of peat and vegetation on permafrost degradation under climate warming was published in Geophysical Research Letters in August and also appeared in Nature Geosciences this month.
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