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The image below zooms in on the large amounts of methane, stretching out all the way from the Beaufort Sea to Baffin Bay.
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This spells bad news, because it implies that, as the sea ice thins, more methane will be able to enter the atmosphere and contribute to warming that is already accelerating in the Arctic.
As discussed in a recent post, methane is rising from the seafloor of the Arctic Ocean due to destabilization of sediments that hold huge amounts of methane in the form of free gas and hydrates. This destabilization is in part due to warm water flowing in the Arctic Ocean along the Gulf Stream. Record warm water was present off the coast of North America in July 2013, and this warm water took some time to reach the Arctic Ocean, as shown on the image below, from that earlier post.
Water in the currents that are returning water to the Atlantic Ocean north of Canada is typically cold, as indicated by the blue color on the image below. So, while it is possible that the water was still sufficiently warm to cause methane releases from the seabed in the Beafort Sea and in Baffin Bay, in the northern parts of Canada, it seems more likely that the methane originated from areas along the fault line that crosses the Arctic Ocean and that the methane traveled - underneath the sea ice - with these currents all the way to the edges of the sea ice where the ice is sufficiently fractured and thin to allow methane to rise to the surface.
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| Image credit: Jack Cook, Woods Hole Oceanographic Institute |
As above image shows, sea surface temperature anomalies (in orange, red and brown) are still showing up prominently along many parts of the Gulf Stream, all the way into the Arctic Ocean, where anomalies of more than 8 degrees Celcius have been recorded for some time now. At the same time, colder water (in green and blue) is flowing back into the Atlantic Ocean from the Arctic Ocean, along the edges of Greenland and further south. Colder currents typically flow at greater depth, but the above image also shows colder waters emerging at sea surface level, especially in areas somewhat off the coasts of Newfoundland and Nova Scotia, effectively preventing some warm water from traveling along the Gulf Stream to the Arctic Ocean.
Why are the currents that are flowing out of the Arctic Ocean into the Atlantic Ocean so strong at the moment? Powerful winds have speeded up these currents, as illustrated by the 30-days Naval Research Laboratory animation below, which also includes a 7-days forecast from November 15, 2013.
One of the feedbacks of accelerated warming in the Arctic is stronger winds and a huge amount of sea ice is currently flowing into the Atlantic Ocean, partly due to these strong winds. Similarly, the Naval Research Laboratory animation below shows huge amounts of sea ice, often very thick ice, being pushed into the Atlantic Ocean.
Last but not least, the youtube video below, Arctic Death Spiral and the Methane Time Bomb, shows some of the most powerful video footage on climate change, highlighting the danger that methane will continue to rise from the seafloor of the Arctic Ocean in ever greater quantities, resulting in a wipe-out of civilization, extinctions at massive scale and devastation of the planet as we know it.
Post by Sam Carana.
Vast amounts of methane are held in sediments under the Arctic Ocean. The Laptev Sea is part of the Eastern Siberian Arctic Shelf (ESAS, the rectangle on the image on the right). Shakhova et al. (2010) estimate the accumulated methane potential for the ESAS alone as follows:
