2013年中国夏季降水动力—统计气候预测及检验分析探讨

Analysis of and Discussion about Dynamic-Statistical Climate Prediction for Summer Rainfall of 2013 in China

  • 摘要: 2013年夏季(6—8月),中国降水呈北多南少的异常分布,东北、华北、四川盆地东部及西北大部降水偏多,而淮河流域至江南大范围地区及青藏高原等地降水偏少。动力—统计预测和动力统计—诊断预测两种方法对夏季北方多雨和长江少雨的总体形势预测基本正确,预测评分(PS)分别为71分和74分,空间距平相关系数(ACC)分别为0.09和0.20。对西太平洋副热带高压、欧亚阻塞高压和东北冷涡区500hPa高度距平场的动力—统计预测结果也较理想,为夏季旱涝分布的诊断预测提供了依据。指出了目前动力—统计预测可能存在的问题,如预测结果对模式预测能力依赖性强,采用多因子选取相似年时,部分因子与降水之间的物理机制不清晰,等等;并指出了可能的解决途径,如通过多模式评估和集合预报来克服预测结果对模式的依赖性,通过深入分析因子对降水的影响机制、因子与降水之间年际关系的年代际变化等来解决因子的筛选问题。

     

    Abstract: The precipitation anomaly distribution over China in the summer of 2013 was seen by the phenomenon of flooding in north and drought in south. More rainfall occurred in northeast China, north China, the eastern Sichuan basin and the most of the northwest China, while less rainfall occurred from the Huaihe river basin to the south of the lower reaches of the Yangtze River, and it also occurred over Tibetan Plateau. Both the dynamic-statistical prediction (DSP) and dynamic statistical-diagnostic prediction (DSDP) have made the approximately correct forecast for the situation of the flood in north and drought in the Yangtze River. The predictive score (PS) is 71 and 74 respectively, while the anomaly correlation coefficient (ACC) is 0.09 and 0.20 respectively. The DSP results of 500hPa height anomalies field in the areas of western Pacific subtropical high, Eurasian blocking high and northeast China cold vortex are ideal, which provided the basis for diagnostic prediction of the summer drought and flood distribution. Finally, the existing problems of DSP were discussed and we pointed out the possible solutions.

     

/

返回文章
返回