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Politics : The Environmentalist Thread -- Ignore unavailable to you. Want to Upgrade?

To: Maurice Winn who wrote (31343)	12/19/2010 12:24:43 AM
From: Land Shark	Read Replies (4) \| Respond to of 36917

You ignore the hot places on earth? Why? I guess just to satisfy yourself that global warming is all just nonsense. Well, that flies in the face of reality: Hot and cold in 2010 Heat records were broken in 17 countries including Belarus, Ukraine, Finland, Russia, Sudan, Niger and Saudi Arabia. Pakistan had Asia's hottest ever recorded day when the temperature in the abandoned city of Mohenjo-daro reached 53.7C (129F). • Pakistan experienced the worst flooding in its history as a result of exceptionally heavy monsoon rains. • The northern hemisphere summer saw exceptional heatwaves in several parts of Eurasia. In Moscow, July mean temperatures were 7.6C above normal, making it the city's hottest month on record by more than 2C. • Ireland and Scotland both experienced their coldest winter since 1962-63. Many other parts of northern and central Europe had their coldest winter since 1978-79. • Canada had its warmest winter on record, with national temperatures 4C above the long-term average; winter temperatures were 6C or more above normal in parts of the country's north. • Most of the continental United States was colder than normal. For the US as a whole it was the coldest winter since 1984-85, and most southern areas from Texas eastwards had one of their 10 coldest winters on record. • Parts of the Amazon basin were badly affected by drought with the Rio Negro, a major Amazon tributary, falling to its lowest level on record. Earlier in the year, Guyana and the eastern Caribbean islands were badly affected by drought. • In Asia, parts of southwestern China experienced severe drought through late 2009 and early 2010. Yunnan and Guizhou provinces both had their lowest rainfalls on record

To: Maurice Winn who wrote (31343)	12/20/2010 11:21:40 AM
From: Wharf Rat	Read Replies (1) \| Respond to of 36917

2012 will be the 4th winter in a row like that. Only cuz of GW, which leaves too much open water in the arctic at the end of summer. Elementary planetary physiology. Cold winter in a world of warming? Last June, during the International Polar Year conference, James Overland suggested that there are more cold and snowy winters to come. He argued that the exceptionally cold snowy 2009-2010 winter in Europe had a connection with the loss of sea-ice in the Arctic. The cold winters were associated with a persistent ‘blocking event’, bringing in cold air over Europe from the north and the east. Last year’s cold winter over northern Europe was also associated with an extreme situation associated with the North Atlantic Oscillation (NAO), with the second lowest value for the NAO-index on record (see figure below). In a more recent press-release, Vladimir Petoukhov and Vladimir Semenov, argue that Global Warming could cool down winter temperatures over Europe, and a reduced sea-ice extent could increase the chance of getting cold winters. Also they propose that cold winters are associated with the atmospheric circulation (see schematic below), and their press-release was based on a paper in Journal of Geophysical Research (JGR), which may seem to have a serendipitous timing with the cold spell over Europe during the last weeks. However, the original manuscript was submitted in november 2009 (before the statement made by James Overland) and accepted in May 2010. One could regard the paper more as a ‘prediction’ rather than an ‘explanation’. I think it is important too keep in mind that the Petoukhov and Semenov study is based on a global atmosphere model that simulated a non-linear response to the loss of sea-ice in the Barents-Kara seas: intially warm winters, followed by cold, and then warm winters, as the sea-ice extent is gradually reduced. One interesting question is how the Barents-Kara sea-ice affects the winter temperatures over the northern continents. By removing the sea-ice, the atmosphere above feels a stronger heating from the ocean, resulting in anomalous warm conditions over the Barent-Kara seas. The local warming gives rise to altered temperature profiles (temperature gradients) along the vertical and horizontal dimensions. Changes in the temperature profiles, in turn, affect the circulation, triggering a development of a local blocking structure when the sea-ice extent is reduced from 80% to 40%. But Petoukhov and Semenov also found that it brings a different response when the sea-ice is reduced from 100% to 80% or from 40% to1%, and hence a non-linear response. The most intriguing side to this study was the changing character of the atmospheric response to the sea-ice reduction: from a local cyclonic to anti-cyclonic, and back to cyclonic pattern again. These cyclonic and anti-cyclonic patterns bear some resemblance to the positive and negative NAO phases. Read Full realclimate.org index.php/ archives/ 2010/ 12/ cold-winter-in-a-world-of-warming/