by Caitlin Douglas
The Arctic covers 5% of the total land mass of the earth and reaches across every longitude: it is important. It is estimated that 1.4 times more carbon is stored in permafrost than is currently circulating in the atmosphere, and there is 1.5 times more carbon in permafrost than is currently being stored in all the earth’s vegetation. William Bowden (2010) outlines this in a Geography Compass article, and explains the relationships between permafrost, thermokarsts and climate change.
Permafrost is soil or rock which remains below 0oC for at least 2-3 years at a time. When permafrost thaws it loses its internal structure and subsides unevenly, and the resulting formation is called thermokarst. The transition from permafrost to thermokarst has important hydrological, geomorphological, biogeochemical and ecological importance to arctic landscapes. Globally, this transition may also release the stored carbon which, due to microbial processes, may be released as carbon dioxide or methane.
In April, a special edition on climate change was published by the journal, Philosophical Transactions of the Royal Society. It outlined key research questions required to better understand the impact of greenhouse gases on climate change. The arctic was prominently featured, and in particular the concern over permafrost melt and potential methane release. Scientists seem to agree that research is needed to understand the transitional process from permafrost to thermokarsts and the possible implications on the global climate.
Bowden, W. 2010. Climate Change in the Arctic – Permafrost, Thermokarst, and Why They Matter to the Non-Arctic World. Geography Compass, 4(10): 1553-1566
Scientists call for climate change early-warning system. The Guardian. April 18th 2011.