摘要
【目的】全球气候变化下,极端气候事件发生的频率、强度等日益增强,其可对流域环境等产生重大影响。大渡河流域不仅是我国长江上游生态屏障和川滇生态屏障的重要组成部分,也是长江流域干旱半干旱河谷的重点分布区域,流域内保护鱼类分布较多,对气候变化敏感。为此,探究大渡河流域极端气温指数时空分布特征。【方法】以大渡河流域为研究对象,基于该流域1964—2018年共55年的逐日气象数据,采用线性拟合、Sen′s斜率估计以及Mann-Kendall非参数检验等方法对大渡河流域的极端气温指数进行了分析;利用协同克里金法进行空间插值,分析了极端气温指数的空间分布规律。【结果】大渡河流域极端气温事件存在明显的年际变化,16个极端气温指数中有11个指数呈上升趋势,5个指数呈下降趋势。除气温极值外,上升速率最快的是SU25,上升速率为2.0 d/10 a;下降速率最快的是FD0,下降速率为1.6 d/10 a。除CSDI和WSDI在流域内变化趋势为0外,其余各极端气温指数变化速率在空间分布上有明显的差异性,海拔高度为导致大渡河流域极端气温指数空间分布特征的主要影响因子。【结论】在时间尺度上,大渡河流域极端气温指数中表征暖的指数均呈上升趋势;表征冷的指数(除TNn和TNx外)均呈下降趋势;其他指数中GSL上升速率较快。这表明该流域在近55年内整体呈变暖趋势,冬季变短夏季变长,且适宜植被生长的温度持续时间增长。突变检验表明各极端气温指数突变除TN10外均为显著突变,且突变年份集中在2000年前后。在空间尺度上,冷指数中ID0、FD0上游上升速率高于中下游,暖指数中TR20、SU25中下游上升速率大于上游,GSL上游上升速率明显高于中下游。流域整体呈变暖趋势且中下游更容易发生极端高温事件。研究成果可为大渡河流域极端气候灾害预警和水生态保护提供科学依据。
[Objective]Under global climate change,the frequency and intensity of extreme climate events are increasing,which have a significant impact on the basin environment.The Dadu River Basin is not only an important part of the ecological barrier in the upper reaches of the Yangtze River and the Sichuan-Yunnan ecological barrier,but also a key distribution area of the arid and semi-arid valleys in the Yangtze River Basin,and there are many protected fish species in the basin,which is sensitive to climate change.The spatiotemporal distribution characteristics of extreme temperature index in Dadu River Basin were explored.[Methods]The Dadu River Basin was taken as the research area.Based on the daily meteorological data of the basin from 1964 to 2018,the extreme temperature index of the Dadu River Basin was analyzed by linear fitting,Sen′s slope estimation and Mann-Kendall nonparametric test.The spatial distribution of extreme temperature index was analyzed by using the co-Kriging method.[Results]The extreme temperature events in the Dadu River Basin have obvious interannual changes.Among the 16 extreme temperature indices,11 indices showed an upward trend and 5 indices showed a downward trend.In addition to the extreme temperature,the fastest rising rate is SU25,the rising rate is 2.0 d/10 a;the fastest decline rate is FD0,and the decline rate is 1.6 d/10 a.Except for the change trend of CSDI and WSDI in the basin is 0,the change rate of the other extreme temperature indexes had obvious differences in the spatial distribution,and the altitude is the main influencing factor leading to the spatial distribution characteristics of the extreme temperature indexes in the Dadu River Basin.[Conclusion]On the time scale,the warm index in the extreme temperature index of the Dadu River Basin showed an upward trend;the cold index(except TNn and TNx)showed a downward trend.In other indexes,GSL rises faster.This indicates that the basin has shown a warming trend in the past 55 years,with shorter winter and longer summer,and the temperature duration suitable for vegetation growth has increased.The mutation test showed that the mutations of each extreme temperature index were significant except for TN10,and the mutation years were concentrated around 2000.On the spatial scale,the upward rate of ID0 and FD0 in the cold index is higher than that in the middle and lower reaches,the upward rate of TR20 and SU25 in the warm index is higher than that in the upper reaches,and the upward rate of GSL in the upper reaches is significantly higher than that in the middle and lower reaches.The whole basin is warming and the middle and lower reaches are more prone to extreme high temperature events.This study can provide a scientific basis for early warning of extreme climate disasters and water ecological protection in the Dadu River Basin.
作者
张志昊
李晓兵
张鹏
梁瑞峰
王庆丰
郭为
王远铭
李克锋
ZHANG Zhihao;LI Xiaobing;ZHANG Peng;LIANG Ruifeng;WANG Qingfeng;GUO Wei;WANG Yuanming;LI Kefeng(State Key Laboratory of Hydraulics and Mountain River Engineer,Sichuan University,Chengdu 610065,Sichuan,China;China Water Beifang Investigation,Design&Research Co.,Ltd.,Tianjin 300222,China;China MCCS Group Corp.Ltd,Chengdu 610063,Sichuan,China)
出处
《水利水电技术（中英文）》
北大核心
2024年第9期10-25,共16页
Water Resources and Hydropower Engineering
基金
国家重点研发计划项目(2022FY100203)
国家自然科学基金项目(U2240212)。
关键词
极端气温
时空分布
大渡河流域
气候变化
长江流域
MANN-KENDALL检验
克里金法
水生态保护
extreme temperature
spatial and temporal distribution
Dadu River Basin
climate change
Yangtze River Basin
Mann-Kendall test
Kriging method
water ecological protection
