Steve Connor The Independent 4 Feb 12;
A loss of sea ice could be a cause of the bitter winds that have swept across the UK in the past week, weather experts say
The bitterly cold weather sweeping Britain and the rest of Europe has been linked by scientists with the ice-free seas of the Arctic, where global warming is exerting its greatest influence.
A dramatic loss of sea ice covering the Barents and Kara Seas above northern Russia could explain why a chill Arctic wind has engulfed much of Europe and killed 221 people over the past week.
The death toll from Arctic blast has been particularly severe in the Ukraine, where many of the dead have been people sleeping on the streets. Heating and food tents have been set up to ease their hardship. In Romania 24 people are known to have died and 17 in Poland.
A growing number of experts believe complex wind patterns are being changed because melting Arctic sea ice has exposed huge swaths of normally frozen ocean to the atmosphere above.
In particular, the loss of Arctic sea ice could be influencing the development of high-pressure weather systems over northern Russia, which bring very cold winds from the Arctic and Siberia to Western Europe and the British Isles, the scientists believe. An intense anticyclone over north-west Russia is behind the bitterly cold easterly winds that have swept across Europe and some climate scientists say the lack of Arctic sea ice brought about by global warming is responsible.
"The current weather pattern fits earlier predictions of computer models for how the atmosphere responds to the loss of sea ice due to global warming," said Professor Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research. "The ice-free areas of the ocean act like a heater as the water is warmer than the Arctic air above it. This favours the formation of a high-pressure system near the Barents Sea, which steers cold air into Europe."
Sea ice covering the Barents and Kara Seas has been exceptionally low this winter, according to the US National Snow and Ice Data Centre in Boulder, Colorado. But air temperatures above the Barents and Kara Seas have been higher than average. The relatively mild westerly winds that have kept Britain from freezing much of this winter have been blocked by fierce high pressure over north-west Russia, centred on an area just south of the Barents Sea.
Studies by scientists at the Alfred Wegener Institute for Polar and Marine Research have confirmed a link between the loss of Arctic sea ice and the development of high-pressure zones in the polar region, which influence wind patterns at lower latitudes further south. Scientists found that as the cap of sea ice is removed from the ocean, huge amounts of heat are released from the sea into the colder air above, causing the air to rise. Rising air destabilises the atmosphere and alters the difference in air pressure between the Arctic and more southerly regions, changing wind patterns.
Professor Rahmstorf said the Alfred Wegener study confirms earlier predictions from computer models by Vladimir Petoukhov of the Potsdam Institute, who forecast colder winters in western Europe as a result of melting sea ice.
Dr Petoukhov and his colleague Vladimir Semenov were among the first scientists to suggest a link between the loss of sea ice and colder winters in Europe. Their 2009 study simulated the effects of disappearing sea ice and found that for some years to come the loss will increase the chances of colder winters.
"Whoever thinks that the shrinking of some far-away sea ice won't bother him could be wrong. There are complex interconnections in the climate system, and in the Barents-Kara Sea we might have discovered a powerful feedback mechanism," Dr Petoukhov said.
But UK climate researcher Adam Scaife said other complexities are almost certainly influencing the current cold spell. "There is a pretty clear link between the current event and the upper level winds... The winds up at 30km (18.6 miles) altitude are very weak," he said. "We have verified several times using computer model experiments that this leads to high pressure across northern Europe and cold winter conditions in the UK as we see now."
Thirty degrees below – and at least a hundred dead: Europe's big freeze
Shaun Walker The Independent 3 Feb 12;
With record snowfalls, icy winds, and thousands of people trapped in remote villages, much of Central and Eastern Europe is in the grip of a cold snap that has caused more than 100 deaths. Temperatures in parts of Ukraine and other Eastern European countries are hovering around -30C (-22F).
The Adriatic islands of Croatia have had a rare dusting of snow, while in Romania, parts of the Black Sea have frozen over. Several towns in Bulgaria have recorded their lowest temperatures since records began more than a century ago,
At least 11,000 people were trapped in mountain villages in Serbia yesterday as ice and snow made roads impassable. Emergency crews were working to gain access to deliver supplies as the country tackled its coldest winter for decades.
"The situation is dramatic. The snow is up to 5m high in some areas. You can only see rooftops," said Milorad Dramacanin, a member of a helicopter evacuation team. Among those airlifted to safety were mourners who had travelled to a funeral but were unable to get back.
In neighbouring Bosnia, supplies were flown to isolated villages, where locals were forced to dig paths into thick snow that resembled tunnels, and said they had little hope of proper access to the outside world until spring. Some villages have been without electricity for days.
The worst-hit country is Ukraine, where dozens of homeless people have died. Authorities said yesterday that 63 people had died in the past few days, with 41 dying on the streets, eight in hospitals and 14 at home. Nearly 1,000 have been hospitalised with hypothermia or frostbite because the temperature has consistently remained below -20C and on some nights has dipped below -30C. Shelters for the homeless across are handing out tea, coffee and pork fat, while hospitals have been told not to discharge homeless patients.
There have also been deaths in Poland, Bulgaria and Romania. In Poland, the victims have also mainly been homeless people, primarily those who fell asleep in unheated buildings. A further 11 people have died since Friday from carbon monoxide poisoning, according to the Polish fire service. The victims had been using makeshift charcoal heaters in an attempt to warm up.
In many parts of Russia, extreme winter temperatures are normal, and life in cities is continuing more or less as usual, albeit with rather more grumbling. In St Petersburg, where temperatures have dipped below -30C this week days, experts have advised residents to change their diet to keep healthy. "You must not eat fresh vegetables in winter, especially during the peak cold periods," said Pavel Gorbenko, a professor of nutrition. He suggested that Russians should increase their intake of fermented cabbage, as well as use heavy fats such as lard, rather than cooking with light oils. "In winter in -20C, a person cannot survive on sunflower oil, he will either get ill or will slowly fade away," Mr Gorbenko said.
In Siberia, temperatures were even lower, with some regions dipping as low as -50C. In the city of Barnaul, all long-distance buses were cancelled; the drivers said if they broke down en route it would mean certain death for all the passengers.
