There are more open water leads within the ice, and the surface melt of the sea ice is more intensive than before. (scientificamerican.com)
There is not enough melt of sea ice or glaciers to account for it there. (skepticalscience.com)
Just for one example, if it turns out that, between melt of sea ice and Greenland ice, the North Atlantic Current slows or stops, we would expect to see fairly dramatically colder weather in Europe for a while, even thought this condition could be directly linked to results produced by GW (though in the long term, the warming would, presumably eventually overtake the cooling from change in ocean currents). (realclimate.org)