As the Earth's temperature rises, methane-eating bacteria take up less methane from the peat bogs in which they live. This reduction in methane recycling means that if the Earth's temperature continues to rise, more methane from the vast peat bogs around the North pole will be released into the atmosphere. Researchers at Utrecht University have uncovered evidence of this effect. On 29 June, their study will be published in the scientific journal PLoS ONE.
Peat bogs represent the largest natural source of atmospheric methane, a greenhouse gas many times more harmful than CO2. The methane is formed by the breakdown of organic materials in the bogs. The release of methane has also accelerated due to the melting permafrost of the Arctic region.
Bacteria and peat-bog moss symbiosis
A large proportion of the methane released is taken up (recycled) by methane-eating bacteria in the peat bog. These bacteria live in symbiosis with peat-bog moss, supplying additional CO2 to the moss, which in turn provides the bacteria's habitat.
Rising temperatures disrupt this symbiosis, disrupting and making the process less effective. The Utrecht University researchers demonstrated this effect by studying the symbiosis and carrying out a series of experiments at various temperatures.
Snowball effect
Global warming means that in the future not only will more methane be released from Arctic peat bogs, the methane will also be contained less effectively, possibly making substantial contributions to higher temperatures on Earth. The current models for predicting rising temperatures on Earth do not take this process into account and therefore underestimate future temperatures.
Publication
Temperature-Induced Increase in Methane Release from Peat Bogs: A Mesocosm Experiment, Julia van Winden, Gert-Jan Reichart, Niall McNamara, Albert Benthien, Jaap Sinninghe Damsté, PLoS ONE, 29 June 2012.
Further information
Peter van der Wilt, Utrecht University Press Office, +31 (0)30 253 3705, p.m.vanderwilt@uu.nl.