孟加拉湾热带风暴西藏降水的动力相似预报方法

Dynamical Analogue Precipitation Prediction Over Tibetan Plateau Effects By Tropical Storm of the Bay of Bengal

采用结合风暴路径和环流的动力相似预报方法(DA),建立孟加拉湾热带风暴(BBTS)期间在西藏高原的定点、定量降水量预报方法,该方法以钟元等提出的非线性相似系数综合评估BBTS在多元判据下的连续动态相似样本。对2008-2012年共17个风暴的试报结果表明,小雨的TS评分24、48和72小时分别为0.82、0.62和0.58,中雨分别为0.44、0.12和0.24,大雨24小时TS评分为0.15。与MOS方法相比,DA的预报准确率更高,是一种BBTS影响下的西藏降水预报较好的客观预报方法。

Using the dynamical analogue prediction model (DA) combined the storm motion and the general circulation, the model for special location and quantitative precipitation over Tibetan plateau during the period of tropical storms over the Bay of Bengal (BBTS) is constructed. The DA selected the similar samples in continuous dynamic criteria from historical BBTS comprehensively using a non-linear similarity index defined by Zhong Yuan et.al. A forecasting test of 17 storms from 2008 to 2012 shows the TS score of light rain for 24, 48 and 72 hours forecasting is 0.82, 0.62 and 0.58, moderate rain is 0.44, 0.12 and 0.24. DA prediction accuracy is better than the MOS which is an objective prediction method without considering BBTS information. The DA model is skilled for precipitation prediction.