2013年汛期气候预测的先兆信号及其应用

Review of the Precursor and Its Application in Summer Climate Prediction in 2013

本文系统回顾了2013年汛期气候预测的主要先兆信号。其信号特征是:2013年前期赤道中东太平洋呈正常略偏冷的状态、冬季北极海冰异常偏少、青藏高原积雪偏少,这些特征对后期东亚夏季风有明显影响。通过对前期先兆信号的分析,国家气候中心比较准确地预测了东亚夏季风偏强、我国夏季主要多雨带偏北的特征,以及南海夏季风爆发偏早、长江中下游入梅偏晚且雨量少雨期短、华北雨季提前雨量偏多的季节内过程演变趋势。最后对汛期气候预测存在的不足进行了分析和讨论。

The possible precursors of the summer climate in 2013 are reviewed which are that in the winter of 2012/2013, ENSO-neutral with slightly cold condition persists in the central and eastern tropical Pacific, the Arctic sea ice area is significantly less, and the snow cover over the Tibetan Plateau is less than normal. These features have an important impact on the following East Asia summer monsoon. By diagnosing and analyzing the possible influence of these precursors, the features of stronger East Asian summer monsoon and main rainfall belt locating the northern China are successfully captured in the prediction issued by the National Climate Centre of CMA in late March 2013. In addition, the onset date of the South China Sea summer monsoon is earlier, the Meiyu along the middle-low reaches of Yangtze River Valley is less with later onset and short rainfall period, and the rainy season in North China is earlier and more than normal. These intra-seasonal features are all successfully predicted. Finally, the imperfection in the sum mer climate prediction is discussed.