韩江流域近50年极端气候事件的时空变化特征

为掌握南方湿热山区典型流域(韩江)的极端气候事件变化规律和趋势,利用中国气象数据服务共享网和广东省气象局提供的韩江流域及附近13个台站1965—2014年最高气温、最低气温、降水量的日数据资料,通过RClimDex极端气候指数计算软件、IDW空间插值、R/S分析等方法,计算分析了与植被生长水热条件、寒旱灾害直接相关的极端气候指标。结果表明:1)韩江流域极端高温事件增多,极端低温事件减少,气温存在变暖趋势,极端持续指数与极端气温指数呈现出很好的一致性;2)过去50年极端降水指数均有所增加但变化趋势不显著,极端降水表征量级的指数相对表征强度的指数增加速率更快;3)各极端降水指数表现出一定的空间分布差异,但整体上呈现"自东北向西南逐渐递减"的分布格局;4)R/S分析表明流域未来气候究竟存在"暖干化"还是"暖湿化"的倾向具有不确定性。根据极端气候的变化适时调整农业生产布局和结构,积极应对可能出现的情况是十分必要的。

Temporal and spatial characteristics of extreme temperature and precipitation events in Hanjiang River Basin over the past 50 years

The aim of this study is to understand the change rules and tendencies of extreme climate events of Hanjiang River Basin located in hot and humid mountain region and to provide a scientific basis for the reduction of meteorological disasters prevention.Based on daily data for temperature and precipitation from China meteorological data service sharing network and Guangdong 13 meteorological stations in Hanjiang River Basin,the spatio-temporal changes features of extreme temperatures and precipitation from 1965 to 2014 in China,which were related directly to vegetation growth of water hot conditions and cold dry disaster,were investigated by using extreme event defined method,linear tendencies,inverse distance weighting spatial interpolation and rescaled range analysis.The results showed that:1)The extreme high temperature event displayed significant upward trend and extreme low temperature event showed significant downward trend,which reflect the climate warming trend and had a good consistency in Hanjiang River Basin;2)The extreme precipitation index increased with no significant change trend over the past 50 years,and the level index of extreme precipitation increased faster than the intensity index;3)the spatial distribution of extreme precipitation indices showed some differences,but its distribution pattern was "Gradually decreasing from northeast to Southwest" on the whole;4)The rescaled range analysis indicated that the future climate tendency of becoming drier or metter remained uncertain.It is very necessary to actively response to the plausible extreme climate sceuarios and to make timely adjustment to the layout and structure of agricultural production.