Melting, rather than warming, is likely to be the big climate issue of 2013.
Predictions that a major El Niño warming event - and the coming solar maximum - would help make next year the warmest on record now seem wide of the mark. All eyes will probably be on the Arctic instead. Some say therecord loss of sea ice in summer 2012 was a one-off, others that it was the start of a runaway collapse. If the latter, summer sea ice could virtually disappear as early as 2016. What is certain is that the ice reforming now will be the thinnest on record, priming it for destruction next summer.
A new record melt would allow scary satellite images of an even bluer Arctic to coincide with the Intergovernmental Panel on Climate Change's next assessment, due in September (though a draft has been leaked - see "What leaked IPCC report really says on climate change"). Such pictures will be a sombre backdrop as the IPCC raises its previously cautious estimates of future polar melting and the speed of sea-level rise.
With warming of at least 2 °C now unstoppable, politicians at the recent Doha climate talks spent much time discussing how to adapt. What they need is predictions for individual countries. But the IPCC will admit that it still cannot say whether many regions will get wetter or drier. And it will quietly bury its confident predictions, made in 2007, of more frequent droughts, which turned out to rest largely on flawed analyses.
There is growing uncertainty, too, about the outlook for the northern hemisphere. Research in 2012 implicated the fast-warming Arctic in a slowing of the jet stream. This is bringing extreme weather to mid-latitudes, including prolonged cold spells in Europe, Russia's 2010 heatwave, and record droughts in the US in 2011 and 2012. Watch out for more weird weather in 2013.
http://www.newscientist.com/article/mg21628965.300-2013-smart-guide-arctic-melt-will-spark-weird-weather.html
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