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Hi Kevin, Thank you for this article which shows that the Arctic is now warming 8 times faster than the rest of the planet. The commonly held view is that the Arctic is warming just twice as fast as global warming - the global average. This is called "Arctic amplification", as if there were some mechanism that takes the global warming (or the driver of global warming) and amplifies it in the Arctic by a fixed factor. I think this is a misconception. What has happened is that warming in the Northern Hemisphere has heated the currents flowing into the Arctic, which started a retreat of sea ice in the 80s. This retreat led to albedo loss, heating of the Arctic Ocean, and further retreat of sea ice, in a vicious cycle of positive feedback. Because it was a feedback, it had non-linear effects. The sea ice extent has shown a non-linear retreat by its variation from the IPCC sea ice models in the AR4 report of April 2007. The variation started appearing in the 80s, and was marked from 90s onwards. Along with this non-linearity of retreat there was also a non-linear warming of the Arctic. This has built up so that now the Arctic is warming about 8 times faster than the rest of the planet. The Arctic temperature is now several degrees higher than it was thirty years ago, and the largest rise has been in the last decade. This has reduced the temperature gradient between tropics and pole, making the jet stream meander and get stuck, leading in turn to climate extremes, crop failures and an increase in the underlying price of food to above the crisis level in many countries - a level at which people rebel against government because they haven't got enough food. The annual albedo loss gives a heat input to the Arctic which accumulates each year. Assuming albedo loss is now the main driver of Arctic warming, we can expect the warming rate to double by the time we have five or six months of the year with the ocean virtually free of ice (less than 1 million km2).. The non-linear trend lines for various months indicate that this date is around 2020. To allow the Arctic to continue warming and sea ice to melt away would be catastrophic for several reasons. Not only would the food crisis deepen, leading to widespread conflict and starvation, but the escalation of Greenland Ice Sheet melt, permafrost thaw and Arctic methane emissions would be unstoppable, leading to many metres of sea level rise and many degrees of global warming, methane being a potent greenhouse gas. This is why it is essential to cool the Arctic as soon and as quickly as possible. We are rapidly approaching the point of no return. Cheers, John -- On 18/11/2013 20:33, KEVIN COLEMAN wrote: > Now we know where it is and it disproves the theory that global > warming had stalled. > > http://phys.org/news/2013-11-discovery-prompts-global.html#nwlt