This is just one of an excellent series by Greenman (Peter Sinclair) explaining why climate scientists have their knickers in a knot over disappearing Arctic sea ice.
We have two main problems — and many smaller ones — that occur when arctic sea ice melts. One is that the high arctic has worked as a planetary air conditioner for thousands of years. If you’ve ever gone for a walk on a sunny day following a huge snowstorm, everything is so bright that it hurts your eyes. And that’s because the pristine white snow reflects sunlight. In the arctic, the huge expanse of ice and snow ensures that all that sunlight — and energy — bounces harmlessly off into space. If we lose that ice and snow, the dark matter beneath will absorb heat, and accelerate the planet’s warming significantly.
The second problem is that the high arctic permafrost — in all those famous frozen wastelands like Canada, Siberia, and Alaska — holds an unbelievably large cache of methane and CO2. As the permafrost melts, and bacteria get busy, they could potentially release billions of tons of greenhouse gases — even more than humanity has emitted since the start of the industrial revolution. Once that occurs, all bets are off.
I suspect that it’s already happening. Global methane emissions have spiked ominously, and scientists working in Canada, Alaska, Siberia and the Baltic Sea have measured surging methane levels* from landscapes that were once buried beneath snow and ice. It could be even worse, as Russian scientists have measured huge roiling plumes of methane escaping from the Siberian sea floor, something no one expected would happen for hundreds of years, if ever.
That’s why we need to get our shit together.
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*Unlike CO2, methane has a relatively short lifecycle in the atmosphere. But it also possesses 21 times the greenhouse gas potency of carbon dioxide, so we really don’t want it there.