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基于热带气旋时间、路径、强度数据和中国728个气象站点1951~2014年日降水数据,分析了年和季节极端降水广义极值(GEV)分布函数特征及受热带气旋的影响。通过检查年和各季节极端降水的非一致性,发现具有变异点或显著时间趋势的站点占总站点数的比例较低。仅考虑满足一致性的站点,年和各季节极端降水GEV分布上尾部在全国大部分区域表现出厚尾特征,且不具有上边界。总体来看北方厚尾特征重于南方,秋季和冬季明显高于年和夏季。年极端降水厚尾特征受到不同季节极端降水机制的混合影响。而且,热带气旋对中国沿海区域极端降水有重要影响,往往引发大量级极端降水。东南沿海地区最大10场极端降水由热带气旋引发的比例达到60%以上。因此热带气旋趋向于增加沿海区域年极端降水GEV分布形状参数的大小,并控制着曲线上尾部的形状。
Based on the time, path and intensity data of tropical cyclone and the daily precipitation data of China from 729 weather stations from 1951 to 2014, the distribution characteristics of generalized extreme value (GEV) of extreme precipitation in years and seasons and the influence of tropical cyclone are analyzed. By examining the non-uniformities of extreme precipitation over years and seasons, it was found that stations with points of variation or significant temporal trends accounted for a lower percentage of the total number of stations. Considering only sites that are consistent, the upper tail of the GEV distribution over the annual and seasonal extremes shows thick-tail characteristics in most parts of the country and does not have an upper boundary. In general, the thick tail of northern China is heavier than that of the south, while the autumn and winter are significantly higher than the year and summer. The characteristics of the annual heavy rainfall tail are influenced by the mixing of extreme precipitation mechanisms in different seasons. Moreover, tropical cyclones have an important impact on extreme precipitation in the coastal areas of China, often leading to a large number of extreme precipitation. The maximum of 10 extreme precipitation in the southeastern coastal areas is over 60% caused by tropical cyclones. Therefore, tropical cyclones tend to increase the size of GEV distribution shape parameters of annual extreme precipitation in the coastal area and control the shape of the tail on the curve.