11 April 2016, Springer Link, Significant implications of permafrost thawing for climate change control. Large amounts of carbon are stored as permafrost within the Arctic and sub-Arctic regions. As permafrost thaws due to climate warming, carbon dioxide and methane are released. Recent studies indicate that the pool of carbon susceptible to future thaw is higher than was previously thought and that more carbon could be released by 2100, even under low emission pathways. We use an integrated model of the climate and the economy to study how including these new estimates influence the control of climate change to levels that will likely keep the temperature increase below 2 °C (radiative forcing of 2.6 Wm−2). According to our simulations, the fossil fuel and industrial CO2 emissions need to peak 5–10 years earlier and the carbon budget needs to be reduced by 6–17 % to offset this additional source of warming. The required increase in carbon price implies a 6–21 % higher mitigation cost to society compared to a situation where emissions from permafrost are not considered. Including other positive climate feedbacks, currently not accounted for in integrated assessment models, could further increase these numbers. Read More here
Tag Archives: Permafrost
9 December 2015, Washington Post, How the Earth itself could undermine a Paris climate agreement. PARIS — With only three days left, tensions here are rising as countries race to resolve outstanding differences and forge an agreement that — hopefully — will set the planet on a path to avoiding the worst consequences of climate change. The goal is an agreement that would set the world on a path to limit warming to below 2 degrees Celsius, or perhaps even 1.5 degrees Celsius, above pre-industrial levels. But at a news conference here at the Le Bourget conference center Wednesday morning, scientists pointed out a factor that could make hitting these targets quite a lot harder. It’s called permafrost. As the planet warms, this frozen northern soil is going to continue to thaw — and as it thaws, it’s going to release carbon dioxide and methane into the air. A lot of it, it turns out. Potentially enough to really throw off the carbon budgets that have been calculated in order to determine the maximum emissions that we can release and still have a good chance of keeping warming to 2 C or below it. In particular, Susan Natali of the Woods Hole Research Center explained Wednesday that with a very high level of warming, permafrost emissions this century could be quite large indeed. Natali used numbers from the 2013 report of the United Nations’ Intergovernmental Panel on Climate Change, which found that humans can only emit about 275 more gigatons, or billion tons, of carbon (about 1,000 gigatons of carbon dioxide, which has a greater molecular weight) to have a greater than 66 percent chance of limiting warming to 2 degrees C. But out of that limited budget, she said, permafrost emissions could take up some 150 of those gigatons (or about 550 gigatons of carbon dioxide). Read More here
23 November 2015, Aljazeera, Siberia’s melting permafrost fuels climate change. Over the past year, a number of giant, mysterious holes have emerged in Siberia, some as deep as 200 metres. Scientists say the craters may be emerging because the frozen ground, or “permafrost”, that covers much of Siberia has been thawing due to climate change, allowing methane gases trapped underground to build up and explode. Permafrost is ground that is permanently frozen, where the ground temperature has remained below zero degrees Celsius for at least two years. It covers about a quarter of the northern hemisphere’s land surface. When permafrost thaws, microbes digest the plant and animal remains that were locked in the permafrost and release greenhouse gases, carbon dioxide and methane into the atmosphere. The phenomenon is a self-feeding cycle, explained Sarah Chadburn, from the University of Exeter. “Permafrost soils contain vast amounts of carbon, nearly twice as much as is currently in the atmosphere. As the permafrost thaws in a warming climate, the soil decomposes and releases carbon to the atmosphere as carbon dioxide and methane. These are greenhouse gases, and they warm the Earth even more. This leads to more permafrost thawing, more carbon release, and so the cycle continues,” Chadburn said. Read More here
14 May 2015, Climate News Network: Permafrost thaw’s runaway effect on carbon release. Arctic warming is causing organic carbon deep-frozen in the soil for millennia to be released rapidly into the air as CO2, with potentially catastrophic impacts on climate. An international team of scientists has settled one puzzle of the Arctic permafrost and confirmed one long-standing fear: the vast amounts of carbon now preserved in the frozen soils could one day all get back into the atmosphere. Read More here
