2011/12冬季欧洲极寒天气的可能解释（请勿转载） 2011/12冬季发在欧洲大陆的极寒天气是2000年以来发在欧洲大陆最寒冷的极端灾害天气，持续时间长，损失惨重。我们迅速对这个问题进行了研究，并给出了一个新的理论解释，其结果已投《Geophys. Res. Lett.. 通过本文的研究可以预言在全球增暖的大背景下，这样的欧洲极寒天气还会增多。 CO2有两种作用：一引起全球增暖和NAO正位相事件的增多，但同时过强的CO2会引起大西洋storm track的增强，过强的大西洋Storm track会引起NAO从正位相转换成负位相，从而导致欧洲极寒天气的爆发。通过这样的大气内部过程的调节来部分抑制CO2引起的全球增暖，但全球增暖的趋势不会停止。 "Extreme cold events over Europe during the 2011/12 winter and their link with the regime transition of the North Atlantic Oscillation" by Luo and Yao (Submitted to Geophys. Res. Lett.) Abstract In this paper, a case study of the extreme cold European weather occurring during the 2011/12 winter is performed in order to provide a likely explanation for the outbreak of the extreme cold winter event. It is shown that the outbreak of the extreme cold European winter of 2011/12 is attributed to the regime transition of the North Atlantic Oscillation (NAO). When the NAO transits from a positive NAO (NAO) event to an Atlantic-European blocking (ENAO-) event, the decline of the surface air temperature is enhanced over the European continent as well as the precipitation anomaly is enhanced (reduced) in the Northern (Central) Europe. Moreover, it is further found that before the NAO regime transition the Atlantic storm track can exhibit an enhanced Atlantic-European storm track in the Central Europe along the northwest-southeast direction. However, after the NAO transition begins, this storm track can be split into two branches so as to establish double storm tracks due to the ENAO- anomaly feedback. The southern storm track in the Central Europe is weakened and its spatial distribution is similar to that before the NAO transition, while the northern one is enhanced along the poleward side of the Northern Europe. Because the ENAO- event is long-lived, the persistent double storm tracks can be maintained in the European continent to produce persistent low temperatures and precipitation over Europe. Thus, the persistent double storm tracks in the European continent are crucial for the outbreak of the 2011/12 Europe extreme cold weather.
标签: 极寒天气
