Methane Bubbles
Methane now bubbling from Beaufort Sea
Methane hydrates decomposing
Remotely Operated Vehicle observations revealed streams of methane-rich gas bubbles coming from the crests of pingo-like-features (PLFs) – due to warm water influx. We offer a scenario of how PLFs may be growing offshore as a result of gas pressure associated with gas hydrate decomposition.
Abstract
The Arctic shelf is currently undergoing dramatic thermal changes caused by the continued warming associated with Holocene sea level rise. During this transgression, comparatively warm waters have flooded over cold permafrost areas of the Arctic Shelf. A thermal pulse of more than 10°C is still propagating down into the submerged sediment and may be decomposing gas hydrate as well as permafrost. A search for gas venting on the Arctic seafloor focused on pingo-like-features (PLFs) on the Beaufort Sea Shelf because they may be a direct consequence of gas hydrate decomposition at depth. Vibracores collected from eight PLFs had systematically elevated methane concentrations. ROV observations revealed streams of methane-rich gas bubbles coming from the crests of PLFs. We offer a scenario of how PLFs may be growing offshore as a result of gas pressure associated with gas hydrate decomposition.Origin of pingo-like features on the Beaufort Sea shelf and their possible relationship to decomposing methane gas hydrates [Editor’s note: $9 for the full PDF.]
There was an item about this on Monitor on German television a few weeks ago. The methane hydrates could create a horrible feedback loop: rising ocean temperatures dissolve methane hydrates; methane heats up the atmosphere and thus the oceans; more methane dissolves. Etc. Horrible.