长江流域年极端气温的时空变化特征研究

Spatiotemporal variation of annual extreme temperature in the Yangtze River Basin

近年来长江流域极端气候事件频发.该文使用1962—2021年长江流域137个站点的气温数据,从流域和站点两个尺度,利用时间序列趋势和突变检验方法分析了长江流域年极端最低和最高气温的时空变化特征.研究表明:1)长江流域年极端最低和最高气温均呈现显著升高趋势,增长率分别为每10年0.35℃和0.26℃;2)年极端最低和最高气温分别有97.08%(133个)和91.97%(126个)的站点显著升高,长江下游地区的站点年极端最低和最高气温增长较快;3)长江流域年极端最低气温没有发生突变,年极端最高气温在2001年发生增暖突变,突变后气温增速明显提升;4)36.5%的站点(50个)年极端最低气温存在突变,突变发生最多的年份为1994年,长江各游段的站点突变年份均以1990—1998年为主.80.3%的站点(110个)年极端最高气温存在突变,突变发生最多的年份集中在21世纪初,长江各游段的站点突变年份均以1999—2006年为主.该研究同时揭示了长江流域60年来极端气温的增暖趋势和阶段性突变,对于理解区域极端气温时空变化过程,预测未来气候变化趋势,制定防灾减灾策略,指导区域气候治理,实现双碳目标等具有重要的意义.

In recent years,extreme climatic events occurred frequently in the Yangtze River Basin.The paper selected temperature data of 137 stations from 1962 to 2021,and analyzed the temporal and spatial characteristics of annual extreme temperature from the basin and station scales based on time series trend and abrupt detection methods.The results indicated that:1)The annual extreme minimum and maximum temperatures showed significant upward trends,with the growth rates of 0.35℃·(10a^(-1))and 0.26℃·(10a^(-1))respectively.2)The stations with annual extreme minimum and maximum temperatures significantly increased accounted for 97.08%(133 stations)and 91.97%(126 stations)respectively.In the lower reaches of the Yangtze River Basin,the growth rate of annual extreme temperature at stations increased rapidly.3)After a warming abrupt change in 2001,the growth rate of annual extreme maximum temperature increased further,however,there was no abrupt change in the annual extreme minimum temperature.4)36.5%of stations had abrupt changes in annual extreme minimum temperature,which mainly occurred during 1990-1998,especially in 1994.80.3%of stations had abrupt changes in annual extreme maximum temperature,which mainly occurred during 1999-2000,especially in the early 2000s.This study revealed the 60-year warming trend and abrupt change of extreme temperature in the Yangtze River Basin,which is of great significance for understanding the spatial and temporal process of regional extreme temperature,predicting the future climate trend,formulating disaster prevention and mitigation strategies,leading regional climate governance,and achieving carbon peaking and carbon neutrality goals.