North is facing a severe cold for the few weeks. People may be wondering where is the global warming.
Remember the “global” in global warming. Even if every inch of land in the northern hemisphere were unusually cold, that would only represent 20% of Earth’s surface. There’s plenty of warmth elsewhere around the world. National Oceanic and Atmospheric Administration data through November hints that 2009 may end up ranked as the southern hemisphere’s warmest year on record. For the planet as a whole, last year falls solidly among the 10 warmest years of the past 100. And despite all the talk about Earth having cooled since the late 1990s, this past decade trumps the 1990s as the warmest on record.
In most winters, and certainly those in the last 20 years or so, UKs winds normally come from the south-west. This means air travels over the relatively warm Atlantic and UK get mild conditions in the UK. However, over the past three weeks the Atlantic air has been ‘blocked’ and cold air has been flowing down from the Arctic or the cold winter landmass of Europe. The low temperatures in the UK have also been accompanied by snow. This is because areas of low pressure have been running in from the north-east, tracking across the North Sea and picking up moisture along the way, which falls as snow.
The Arctic oscillation(AO) is a measure of north-south differences in air pressure between the northern midlatitudes and polar regions. When the AO is positive, pressures are unusually high to the south and low to the north. This helps shuttle weather systems quickly across the Atlantic, often bringing warm, wet conditions to Europe. In the past month, however, the AO has dipped to astoundingly low levels – among the lowest observed in the past 60 years. This has gummed up the hemisphere’s usual west-to-east flow with huge “blocking highs” that route frigid air southward.
However, it is not cold everywhere in the world. North-east America, Canada, North Africa, the Mediterranean, and south-west Asia have all seen temperatures above normal – in many places by more than 5 °C, and in parts of northern Canada, by more than 10 °C.
The mean UK temperature for December was 2.1 °C, making it the coldest for 14 years and colder than the long-term average for December of 4.2 °C. However, December was one of only two months in 2009 which had a below-average mean temperature.
Climate change is taking place as the earth continues to warm up.
In the UK, 2009 as a whole was the 14th-warmest on record (since 1914). This above-average temperature trend was reflected globally, with 2009 being the fifth-warmest year on the global record (since 1850).
The current cold weather in the UK is part of the normal regional variations that take place in the winter season. It doesn’t tell us anything about climate change, which has to be looked at in a global context and over longer periods of time.
– from metoffice.gov.uk, guardian
People are utilizing current cold weather in Europe to use last drop of oil/coal, push the carbon economy and killing research on renewable source of energy. This is dangerous.