Arctic Methane Emissions Reaching Record Levels
19.01.2010 - Atmosphere & Space, Land & Geology, Arctic
On the heels of a string of reports on the methane emissions from the Arctic permafrost, a new study published in Science shows a massive spike in the amount of methane seeping from Arctic permafrost as it melts. As the study shows, methane emissions have risen by almost one-third in just five years as a consequence of sharply rising temperatures.
Scientists now fear that the release of methane, a greenhouse gas far more potent than carbon dioxide, will lead to increased to even more methane release afterwards, thus causing a faster temperature rise than predicted.
The scientists, who conducted a wider study of methane emissions through global wetlands, have succeeded in finding where methane is being released by combining methane levels in the atmosphere with surface temperature changes. They did not measure methane emissions directly, but instead used satellite data to measure variations in groundwater depth, which alters the way bacteria break down organic matter to release or consume methane.
The scientists were also able to conclude that while over half of all methane emissions came from the tropics, the 31% rise in Arctic methane emissions between 2003 and 2007 had been enough to bring the global average up to 7%.
Although there is no evidence that the Arctic has passed a tipping point, methane emissions in the region have increased by 31% from 2003-07, and projections show that temperatures might have risen by as much as 10°C by 2100 if carbon emissions were to continue to rise at current rates.
The study further shows that serious greenhouse gas monitoring is lacking, particularly as the pair of satellites used for the study are over their expected mission life time.
