Unusual IOD event of 2007
Unusual IOD event of 2007
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DOI：
10.1029/2008gl034122
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发表时间：
2008-07
影响因子：
5.2
通讯作者：
S. Behera;Jing‐Jia Luo;T. Yamagata
中科院分区：
文献类型：
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作者：
S. Behera;Jing‐Jia Luo;T. Yamagata
2007年的印度洋正偶极子与太平洋的拉尼娜现象一起演变，并与2006年的印度洋正偶极子事件相连续。在这两个盆地中，气候异常的混合是极其罕见的。负IOD的演变通常是在正IOD之后发生的，但在2007年北半球夏季发生了逆转。这与海洋表面温度（SST）异常的模式有关，其中海洋大陆较冷的海洋两侧是温暖的中太平洋和印度洋。伴随着海洋大陆的下沉，赤道印度洋东部的东风异常发散，通过海洋动力学触发了连续的正IOD事件。在历史记录中，这种事件的离散发生只有两次; 1967年的正IOD与拉尼娜同时演变，1913年和1914年的正IOD连续演变。这些历史事件是由降雨偶极子指数除了通常的SST偶极子指数。
The positive Indian Ocean Dipole (IOD) of 2007 evolved together with a La Niña in the Pacific and consecutive to a positive IOD event of 2006. It was an extremely rare blend of climate anomalies in those two basins. The evolution of a negative IOD, which normally follows a positive IOD, was reversed during boreal summer of 2007. This was associated with a pattern of sea surface temperature (SST) anomalies in which the colder seas of the Maritime Continent were flanked by the warmer central Pacific and Indian Oceans. The associated subsidence over the Maritime Continent caused divergent easterly wind anomalies in the eastern equatorial Indian Ocean to trigger a successive positive IOD event through ocean dynamics. Discrete occurrences of such events are found only twice in historical records; the positive IOD of 1967 evolved concurrently with a La Niña and the positive IODs of 1913 and 1914 evolved consecutively. Those historical events were recognized by a rainfall dipole index in addition to the customary SST dipole index.