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Several times in the last decade, the warmest decade since temperature records began, Europe has had record heat waves with an associated higher death toll.

What may not be more commonly known are the record breaking winter cold snaps that are now in their third consecutive season.

New record lows have been set in various locations, Ireland with -18.7dC, northern Norway -35dC and -42.1 dC in Sweden in 2010. In Trondhiem Norway the record since 1788 for Novemeber was eclipsed with the end of the month running 12 to 14 dC lower.

A higher death toll has occurred with each of theses events along with massive disruption to normal activities.

This year, although later than the previous cold snaps, because it has occurred in the poorer regions of eastern Europe the death toll has also been high with the Ukraine, a place where cold winters are not uncommon having 101 deaths so far. Bulgaria has had at least 60 die, mostly in the rural areas.

In the past the there has been an unwillingness to link weather events and climate change.

It is understanding that these events are associated with macro changes in the drivers of the climate that can gives us new insights into the near future, where climates become more and more unstable, patterns of the past that determined human geography disappearing.

Recent work at the Research Unit Potsdam of the Alfred Wegener Institute for Polar and Marine Research in the Helmholtz Association has found a relationship between reduced Arctic sea ice and winter cold snaps in central Europe.

If there is a particularly large-scale melt of Arctic sea ice in summer, as observed in recent years, two important effects are intensified.

Firstly, the retreat of the light reflective ice surface reveals the darker ocean, causing it to warm up more in summer from the solar radiation (ice-albedo feedback mechanism).

Secondly, the diminished ice cover can no longer prevent the heat stored in the ocean being released into the atmosphere (lid effect). As a result of the decreased sea ice cover the air is warmed more greatly than it used to be, particularly in autumn and winter because during this period the ocean is warmer than the atmosphere.

The higher temperatures can be proven by current measurements from the Arctic regions.

The warming of the air near to the surface leads to rising movements and the atmosphere becomes less stable.

Analysis of the complex non-linear processes behind this destabilisation has shown how these altered conditions in the Arctic influence the typical circulation and air pressure patterns.

One of these patterns is the air pressure difference between the Arctic and mid-latitudes: the so-called Arctic oscillation with the Azores highs and Iceland lows familiar to watchers of northern hemisphere weather reports. If this difference is high, a strong westerly wind will result, which in winter carries warm and humid Atlantic air masses right down to Europe.

If the wind does not come, cold Arctic air can penetrate down through to Europe, as was the case in the last two winters 2009-10 and 2010-11 and now in 2011-12.

Model calculations show that the air pressure difference with decreased sea ice cover in the Arctic summer is weakened in the following winter, enabling Arctic cold to push down to mid-latitudes.

This may be a new state for European winters for a period as the Arctic sea ice cover fluctuates.

This year the cold snap has arrived suddenly and struck from France to Ukraine. Over 200 people have died, many in the poorer countries of eastern Europe. In the Ukraine 2,500 warming stations have been set up.

Whilst the science has made it clearer and clearer that human emissions are causing the climate to become less stable and will lead to changes that will affect society and thus economies a major struggle within the conservative side of politics has been occurring.

Business interests whose profitability those interests believe will be negatively affected, the high carbon emitting fossil fuel providers and major users, have been involved at various times in campaigns from questioning the affects of government policy changes to attempting to debunk the science of our understanding of the impact of increased atmospheric carbon on the atmosphere.

A recent example is a full page ad shown as a letter signed by 16 leading scientists and published in the New York Times during a critical period in the Republican primaries in the US. Included is the retired Australian scientists William Kinninmonth, who is regularly debunked by other working scientists for his erroneous publications on the climate.

At the same time it has dawned on some other old business interests that they will be negatively impacted if nothing is done and they have lobbied for action by governments in their part of the world. UK targets are now at a 27% reduction in emissions, Brazil at least