Unusual Winter Temperature Related to Circulation of Polar Cold Air

Freezing temperatures have killed at least 160 people across Europe, mainly in Eastern European countries like Ukraine and in Russia.
Western Europe is also under the influence of the cold spell.
Italy is having the coldest winter in nearly 30 years.
Over in Japan, record snowfall has hit the nation, and the death toll from blizzards have claimed over 50 lives.
Meanwhile, many parts of the U.S. are experiencing their warmest winter in 40 years.
The temperature in Washington DC climbed so high recently that even cherry trees began to blossom.
Some states of the U.S. like Texas and New Mexico are even suffering from drought conditions.
According to the Korea Meteorological Administration, this cold snap sweeping across Europe and Northeast Asia, and the warm temperatures in North America, are all-related to a polar atmospheric circulation, caused by the weakened polar jet stream.
Usually, the polar jet stream, which is a current of rapidly moving air, revolves around the arctic regions, but as the jet stream weakens due to higher temperatures in the polar region, the cold air escapes and makes its way down to Europe and Northeast Asia causing the sudden cold snap.
While these areas have been hit with blasts of cold air, the northern part of the U.S. has been spared, leading to the unusually warm temperatures.


[INTERVIEW : Shin Jin-ho, Senior Researcher,Korea Meteorological Administration] ''This winter, the Arctic region has been warming up, and the polar jet stream that kept the polar cold air around the artic region weakened, and the cold air is heading southward to Eastern Europe and Northeast Asia, causing a cold surge and heavy snow fall. But North America is having a warm winter.''

The circulation of polar air is having an effect on temperatures throughout the Northern Hemisphere, another indication that it truly is a small world after all.
Park Ji-won, Arirang News.
FEB 03, 2012