If less of the ocean is ice-covered in autumn, it releases more heat, warming the atmosphere.

This reduces the air temperature difference between the Arctic and latitudes further south, over the Atlantic Ocean.

In turn, this reduces the strength of the northern jet stream, which usually brings milder, wetter weather to Europe from the west.

It is these “blocking” conditions that keep the UK and the other affected regions supplied with cold air.

The researchers also found that the extra evaporation from the Arctic Ocean makes the air more humid, with some of the additional water content falling out as snow.

“I agree with the study – I have no beef with the case that declining Arctic sea ice can drive easterly winds and produce colder winters over Europe,” commented Adam Scaife, head of monthly to decadal prediction at the UK Met Office.

Research in other institutions, including the Met Office, confirmed the argument, he said.

Sadly, the “it’s snowing therefore science is a lie” argument finds lots of takers and this explanation is longer than a commercial, so despite the fact that it explains *and* predicts the observed data, it will be widely dismissed by idiots.
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BBC News – Melting Arctic link to cold, snowy UK winters
http://www.bbc.co.uk/news/science-environment-17143269