Characteristics of atmospheric circulation associated with cold surge occurrences in East Asia: A case study during 2005/06 winter
Characteristics of atmospheric circulation associated with cold surge occurrences in East Asia: A case study during 2005/06 winter
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DOI：
10.1007/s00376-008-0791-0
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发表时间：
2008-09
影响因子：
5.8
通讯作者：
T. Park;Jee-Hoon Jeong;Chang‐Hoi Ho;Seong‐Joong Kim
中科院分区：
文献类型：
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作者：
T. Park;Jee-Hoon Jeong;Chang‐Hoi Ho;Seong‐Joong Kim
研究了2005/2006年冬季东亚两次明显冷潮爆发期间的高层环流特征和热力特性。 2005年12月上旬至2006年1月上旬，由于2005年12月2日和2006年1月2日连续发生两次寒潮，特冷天气持续约一个月。研究表明，两者都涉及对流层上层环流，导致西伯利亚高压向东亚方向放大和扩展，但产生的原因不同：前者是由来自北太平洋的上层阻塞引起的，后者是由穿越欧亚大陆的上层波列引起的。特别是，高层环流异常引起的对流层低层异常风和锁相年循环放大的陡峭经向温度梯度共同作用，在东亚引发了很强的冷平流，导致持续数周的异常寒冷天气。目前的结果强调，对流层上层环流的特征可以被认为是东亚寒潮发生的重要前兆。
The characteristics of the upper-level circulation and thermodynamical properties for the period when two distinct cold surges broke out over East Asia during the 2005/06 winter are investigated. From early December 2005 to early January 2006, exceptionally cold weather lasted for approximately one month due to two successive cold surges that took place on 2 December 2005 and 2 January 2006, respectively. This study reveals that both involve the upper-tropospheric circulation, which induces the amplification and expansion of the surface Siberian high toward East Asia, but arose from different causes: the former is caused by the upper-level blocking originated from the North Pacific and the latter is caused by the upper-level wave train across the Eurasian Continent. In particular, it is suggested that the lower-tropospheric anomalous wind caused by upper-level circulation anomalies and a steep meridional temperature gradient amplified by phase-locked annual cycle combined to induce very strong cold advection in East Asia, which resulted in exceptionally cold weather that lasted for several weeks. The present results emphasize that the characteristics of the upper-tropospheric circulation can be considered as important precursors to cold surge occurrences in East Asia.