江苏省近45a极端气候的变化特征

Characteristic of extreme climate change over Jiangsu Province in the last 45 a

利用江苏省35个测站1960—2004年45 a的逐日最高温度、最低温度、日降水量资料集,分析了近45 a江苏省极端高温、极端低温以及极端降水的基本变化特征。结果表明:(1)多年平均年极端高温的空间分布表现为西高东低,而极端低温则表现为自北向南的显著增加,极端降水的发生频次自南向北逐渐减少;(2)极端高温在江苏中部以及南部大部分地区有上升趋势,而西北地区则有弱的下降趋势;全省极端低温表现为显著的升高趋势;极端降水频次在南部地区有增加的趋势,北部减少趋势,中部则无变化趋势。(3)江苏极端高温、低温和极端降水的年际和年代际变化具有区域性差异,其中极端降水频次变化的区域性差异最为明显。

By using 1960--2004 daily maximum temperature, minimum temperature and daily rain- fall data of 35 stations over Jiangsu Province, the basic features of extreme climate events such as extreme maximum temperature, extreme minimum temperature and extreme precipitation events in the last 45 a are investigated. Results show that： （1）The climatological annual extreme high temperature in west part of Jiangsu are higher than that in the east, but the extreme low temperatures increase south-ward evidently. The frequency of the extreme precipitation events decrease from the north to the south. （2）Increasing trends of the extreme high temperature are found over both the central and southern regions, but a weak decreasing trend in north-western region. The extreme low temperatures increase significantly over most regions. Increasing and decreasing trends are found in the frequencies of the extreme precipitation events over the south and north parts respectively, but no evident long-term trend in central Jiangsu. （3） Regional differences exist in the inter-annual and inter-deeadal varibilities of the extreme high, low temperatures and extreme precipitation events.