The 1997/98 Summer Rainfall Season in Southern Africa. Part II: Model Simulations and Coupled Model Forecasts
The 1997/98 Summer Rainfall Season in Southern Africa. Part II: Model Simulations and Coupled Model Forecasts
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1997/98 南部非洲夏季雨季。
DOI：
10.1175/2009jcli2600.1
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发表时间：
2009
影响因子：
4.9
通讯作者：
S. Mason
中科院分区：
文献类型：
--
作者：
B. Lyon;S. Mason
摘要这是对1997/98年强厄尔尼诺期间南部非洲降雨量的两部分调查的第二部分。第一部分表明，在1997/98年厄尔尼诺期间，南部非洲的大范围干旱通常没有在1997/98年厄尔尼诺期间发生，尤其是在1998年1月至3月期间。本文检验了三个大气环流模式(AGCM)与观测海面温度(SSTs)强迫的输出和三个耦合模式的季节预报，以了解JFM1998年的情况在多大程度上是可以预测的。这三种模式都在整个南部非洲造成了类似于过去厄尔尼诺事件期间的大范围干旱情况，在产生观测到的降雨和大气环流异常模式方面普遍做得很差，特别是在东印度洋和南印度洋。相比之下，三个耦合模型中的两个显示出更潮湿的条件的可能性更高。
Abstract This is the second of a two-part investigation of rainfall in southern Africa during the strong El Nino of 1997/98. In Part I it was shown that widespread drought in southern Africa, typical of past El Nino events occurring between 1950 and 2000, generally failed to materialize during the 1997/98 El Nino, most notably during January–March (JFM) 1998. Here output from three atmospheric general circulation models (AGCMs) forced with observed sea surface temperatures (SSTs) and seasonal forecasts from three coupled models are examined to see to what extent conditions in JFM 1998 could have potentially been anticipated. All three AGCMs generated widespread drought conditions across southern Africa, similar to those during past El Nino events, and did a generally poor job in generating the observed rainfall and atmospheric circulation anomaly patterns, particularly over the eastern and southern Indian Ocean. In contrast, two of the three coupled models showed a higher probability of wetter conditions ...