Reply to post: Re: Interesting idea

Re: Interesting idea

1: Yes - and in ways you probably don't realise

- forget temperature changes, the oceans have increased 30% in acidity in the last 200 years (pH is a log scale) and zooplankton are having trouble forming shells. In geological history, every time that's happened there's been a global anoxic event and the consequences for life on land have been severe (in the short term it would also cause an oceanic food chain collapse which means lots of starving people) - It's all there in the rocks.

2: See above. How well can our species (and most others) cope with a reduction of atmospheric oxygen to 18%?(equiv 4000 feet at sea level) 16%? (equivalent 8,000 feet at sea level) or lower? Half the planet's breathable oxygen comes from the sea and during anoxic events the rocks show it's typically dipped to 13-14% (10,000 feet seal level equivalent). Can we cope with half the land area of the planet being rendered effectively uninhabitable?

The heat - of water, not air - is a real problem.

Tongues of warm water coming in from the Atlantic are destabilising methane clathrates on the Siberian continental shelf/margin (google for "laptev methane emissions") - and whilst what's coming out _now_ is relatively minor (the Russian establishment has started trying to play it down after blanking all coverage for 6 years and they still won't allow independent investigators into the areas), bear in mind that 20 years ago scientists were saying that all such emissions would dissolve into the water coloumn and it would be impossible for gas to make it to the surface (the plumes were about 1km wide at the surface in 2011) - what should worry you is that as the clathrates gas out, it makes the ice that remains porous, more and more unstable and more likely to break loose in a submarine landslide if there's an earthquake - which happen relatively regularly across the arctic.

Submarine landslide-induced mass methane emissions have happened before - we know the most famous of them as the "Storegga Slides" and those were right on the knee point of warming at the start of our current interglacial period (after the slides, temperatures shot up sharply as did sea levels) - only this time there's the added fun of somewhere between 5-25gigatonnes of methane (carbon) that we can't afford to be added to the atmosphere to think about as well.

The Global Methane Survey announced a few years back that they'd found 25% more methane in the atmosphere than they could account for from their satellite surveys and blamed it on possible farm animal emissions - but they didn't know about the Laptev Sea and their instruments weren't tuned to pick up methane over water, nor were the satellites in a high enough orbit to measure it anyway (they tried to recheck the raw data when it was brought to their attention (The reaction when shown the reports out of Russia before things clammed up was "What the? Uh oh!").

There's a new methane survey underway using new instruments but it will take at least a couple of years to see if the "mystery" sources are clathrates. If they are, we may already have _at least_ 3-5C locked in.