Methane Releases from the Arctic to Have Large Impact on Seas Worldwide
08.07.2010 - Atmosphere & Space, Land & Geology, Arctic
A new study published in the Geophysical Research Letters, suggests that massive releases of methane from the Arctic seabed could cause oxygen-depleted dead zones, sea acidification and disrupt ecosystems in several areas of the northern oceans. These events, the scientists involved in the study say, could happen if global warming triggers a widespread release of methane the Arctic seabed.
Until now, immense amounts of methane were deeply buried in permafrost and high-latitude ocean sediments. Seas such as the Kara, Barents and East Siberian Sea in the Arctic Ocean appear to be holding significant amounts of methane. While many surveys have already underlined the presence of methane plumes rising from the ocean floor, climate warming in coming decades is likely to extend even further into the deep sea, releasing as much as 16,000 metric tons of methane each year.
This release could not only lead to large volumes of acidified water and low-oxygen dead zones, but could also rob the key nutrients for microbial activity from the water, thus causing a shift in populations at the base of the ocean’s food chain in many regions.
Future work will refine the new study’s preliminary results. In areas where river deltas inject organic material and dissolved trace elements into the sea, the impact of the interrelated processes on water chemistry is not clear and requires further investigation.