A Major Masking effect of global atmospheric and ocean temperatures is caused by melting ice caps, and the vast majority of this so called "Ice cube effect" is caused by the Arctic ice melt.
The Gulf Stream is threatened by a massive increase in cold water volume spreading south from the melting polar ice cap.
Scientists worry that the Gulf Stream mechanism will be switched off altogether by this massive frigid southward tide, radically changing the northwestern European climate from temperate to arctic.
The Gulf Stream is powered by the freezing of sea water in the Arctic which sends brine down into the deep Atlantic to be replaced by surface water (the Gulf Stream) sucked northward from around Florida.
"The jet stream, which operates between the cold Arctic and the warmer mid-latitudes, dominates much of our weather, and it is weakening and becoming more erratic as Arctic ice melt accelerates and the region warms. The severe cold snaps that brought Ireland to a shivering halt in 2010 and 2011, as well as this summer’s relentless rainfall, are probably connected to Arctic ice cover loss"
“We’re in uncharted territory,” says James Overland of the University of Washington. The weakening jet stream means “wild temperature swings and greater numbers of extreme events”. The last time the Arctic is believed to have been ice-free is during the Eemian period, about 125,000 years ago, when global sea levels were between four and six metres higher than today. However, current atmospheric CO2 levels are already far higher than during the Eemian; indeed, you would have to go back several million years to find any era in the Earth’s history to match today’s levels of this powerful heat-trapping “greenhouse gas”
Lags and masking effects in the system mean that we have so far experienced only the very mildest of the effects of the ever-growing heat imbalance in our climate system. In July, another stark regional landmark was recorded. In the course of just four days, surface ice melt spread from 40 to 97 per cent of Greenland.
Not to mention the fact that China recently cruised through the Arctic passage in it's own icebreaker, and Russia has begun upgrading it's fleet of nuclear icebreakers too #foreignpolicy
Sailing along the coast of Siberia by the north-east passage, or Northern Sea Route (NSR), as Russians and mariners call it, cuts the distance between western Europe and east Asia by roughly a third.
The passage is now open for four or five months a year and is getting more traffic. In 2010 only four ships used the NSR; last year 34 did, in both directions, including tankers, refrigerated vessels carrying fish and even a cruise liner.