Climate crisis: Plumes of methane stretching 'hundreds of kilometres' rising from Arctic seabed

[Celerity]

First documented evidence of large-scale release of potent greenhouse gas from region may have ‘serious climate consequences’

https://www.independent.co.uk/environment/methane-arctic-seabed-greenhouse-gas-emissions-climate-siberian-shelf-study-expedition-b1396150.html



Scientists have found alarming new evidence that large quantities of previously frozen methane deposits on the Arctic seabed are beginning to be released into the sea and the atmosphere - a process which could rapidly speed up global heating. Scientists aboard the research vessel Akademik Mstislav Keldysh on the International Siberian Shelf Study Expeditions 2020 have reported “hundreds of kilometres” of bubble clouds erupting from the continental slope off the East Siberian coast.

The preliminary research, carried out by teams still on the ship, indicate large amounts of methane are bubbling up from part of the Laptev Sea slope, with some of the potent greenhouse gas dissolving into the water, and some being released into the air. “We documented bubble clouds rising from about 300 m depth along 150 km of Laptev Sea slope, and confirmed high methane concentrations by hundreds of onboard chemical analysis,” the scientists said in a Facebook post.

“This may be the first comprehensive observation of active release from methane hydrates on the Siberian-Arctic slope system,” the team added. When methane is released into the atmosphere, it is 86 to 105 times as powerful as carbon dioxide at disrupting the climate over a 20-year period. Vast amounts of methane are stored in the Arctic in natural gas deposits, permafrost, and as undersea clathrates - a solid compound of water and methane similar to ice.

Like the permafrost on land, clathrates degrade on warming, releasing the stored methane which then causes further warming. This in turn can stimulate both the production of methane (through the rotting of organic material), and its release, in a heating feedback cycle. Temperatures in the region are already well above average, with global warming having a greater impact at the planet’s poles - particularly in the northern hemisphere. This is known as the Arctic amplification phenomenon - temperatures in northern polar regions have risen at least twice as fast as other parts of the globe amid the climate crisis. The shelf sediments of the Laptev and East Siberian Seas, are “actively venting bubbles and strong methane signals”, the researchers said.

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'Sleeping giant' Arctic methane deposits starting to release, scientists find

Exclusive: expedition discovers new source of greenhouse gas off East Siberian coast has been triggered

https://www.theguardian.com/science/2020/oct/27/sleeping-giant-arctic-methane-deposits-starting-to-release-scientists-find



Scientists have found evidence that frozen methane deposits in the Arctic Ocean – known as the “sleeping giants of the carbon cycle” – have started to be released over a large area of the continental slope off the East Siberian coast, the Guardian can reveal. High levels of the potent greenhouse gas have been detected down to a depth of 350 metres in the Laptev Sea near Russia, prompting concern among researchers that a new climate feedback loop may have been triggered that could accelerate the pace of global heating.

The slope sediments in the Arctic contain a huge quantity of frozen methane and other gases – known as hydrates. Methane has a warming effect 80 times stronger than carbon dioxide over 20 years. The United States Geological Survey has previously listed Arctic hydrate destabilisation as one of four most serious scenarios for abrupt climate change. The international team onboard the Russian research ship R/V Akademik Keldysh said most of the bubbles were currently dissolving in the water but methane levels at the surface were four to eight times what would normally be expected and this was venting into the atmosphere.

“At this moment, there is unlikely to be any major impact on global warming, but the point is that this process has now been triggered. This East Siberian slope methane hydrate system has been perturbed and the process will be ongoing,” said the Swedish scientist Örjan Gustafsson, of Stockholm University, in a satellite call from the vessel. The scientists – who are part of a multi-year International Shelf Study Expedition – stressed their findings were preliminary. The scale of methane releases will not be confirmed until they return, analyse the data and have their studies published in a peer-reviewed journal.

But the discovery of potentially destabilised slope frozen methane raises concerns that a new tipping point has been reached that could increase the speed of global heating. The Arctic is considered ground zero in the debate about the vulnerability of frozen methane deposits in the ocean. With the Arctic temperature now rising more than twice as fast as the global average, the question of when – or even whether – they will be released into the atmosphere has been a matter of considerable uncertainty in climate computer models. The 60-member team on the Akademik Keldysh believe they are the first to observationally confirm the methane release is already under way across a wide area of the slope about 600km offshore.

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[Roland99]

1. that's a bit more than cow farts, eh?

[Miguelito Loveless]

2. That is "Game Over"

for a livable climate. Now things start changing faster, and faster, like crossing the event horizon of black hole.

[Mike 03]

3. This is what I've read too.

It's tough to read this.

[Kaleva]

4. Climate change isn't going to be uniform around the world

What is predicted to happen where you currently live?

[Miguelito Loveless]

7. Of all the scenarios that worried climate scientists

this is the one that gave them nightmares. Once this feedback loop begins, there is really no practical way to stop it, that wouldn't be as bad, or perhaps worse than the runaway warming scenario.

In my neck of the woods (NC) we have seen warmer winters, more rain and flooding, followed by prolonged heat spells 90°+.

We are looking at the loss of the Outer Banks, and massive loss of coastline. More flooding, and extremely high temps, with high humidity.

[LAS14]

5. So bad it's more depressing than the Trump presidency!!! nt

[CrispyQ]

6. There's a stark beauty to that bottom photo.

We are so fucked we don't even know how fucked we are. And the rich (mostly) men who brought us to this brink still think they are superior and deserve to be in charge. It's boggling.