Freezing Britain and methane bombs

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This week, we are having unseasonable cold weather in the UK. Normally, at this time of year (end of February), temperatures here would be climbing into double figures as the sun rises higher in the sky. Instead, we are gripped with freezing day-time conditions, a sub-zero easterly wind and a fair amount of snow.

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Some readers might conclude that such cold weather shows that fears of global warming are unfounded, or perhaps highly exaggerated. Tragically, this latest weather phenomenon, a mass-movement of cold air south, from the Arctic, is an indication that the opposite is true.



The reason why this ‘Beast from the East’, as this weather systems has been called, is so alarming is all to do with the jet stream (as explained in the above BBC video). The jet stream is a fast, circular flow of air in our atmosphere, over our Arctic. For many millennia, the jet stream has acted as a ‘wall’ of fast-moving air that holds cold air in, over the Arctic and prevents warm air moving north into the Arctic. Because the Arctic has been warming due to climate change, and losing its expanse of sea-ice, the mean air temperature in the Arctic has been increasing. This temperature rise has weakened the jet-stream. As a result, the Arctic cold air is no longer being held in. Large amounts of it can now slide south. This is the cause of the UK’s current cold snap.

The scary side-effect of this cold air moving south is that warm air has moved into the Arctic to replace that mass of cold air. This change might not seem particularly worrying to people in the UK, but there is a vast amount of methane locked into the shallow sea floor around the Arctic, covering an area at least the size of Western Europe. If the waters above these methane deposits warm much more, they will melt the sea-floor ice that is holding the methane in, akin to removing the cork on a bottle of champagne. A vast amount of methane will then be released.



The above video explanation of this effect from Paul Beckwith, published last year, covers all the main points.

The last time such a sea floor methane burst happened was probably in around 6000 BC off the coast of Norway. It became known as the Storegga Slide. The release was akin to a vast underwater gas explosion. It created a huge wall of water (marked in the Wikipedia diagram below) that decimated the East Coast of the UK, among others, and significantly warmed our planet in one, violent act. Methane does not stay in our atmosphere as long as carbon but it is forty times more powerful as a greenhouse gas and so its effect is short-lived but severe.

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A recent climate change study, reported in the Guardian newspaper last month, from scientists the University of Exeter, stated that the extreme predictions for our future warming are 'not credible'. This scientific ‘reduction in danger’ message caused a lot of people to conclude that the climate-change alarm calls have been exaggerated, hysterical etc. In fact, as the scientists concerned admitted themselves, they did not take into account any tipping points or negative feedback mechanisms in their predictions. This included ignoring the Arctic permafrost methane emission-temperature bomb.

This weeks unseasonable freezing conditions are therefore not a cause for relief or scepticism about the climate change threat. Instead, as Paul Beckwith states in his video, our cold snap should be a cause for serious alarm. If we ignore the significance of these anomalous and extreme cold air movements out of the Arctic, and we simply wait until there is another Storegga Slide, it'll be too late. A future Mega-Arctic-Slide's catastrophic decimation of our coasts might convince as to our planet’s accelerating climate meltdown, but by that time it will be far too late.

postscript: It's a day later and this article reports that the Arctic temperatures have shot up to around twenty degrees centigrade higher than the normal temperature for this point in the year. Although the article mainly discusses the general issue of climate change, the risk of a permafrost-methane eruption is mentioned at the end.