气候变化背景下西藏高原地区界限温度时空变化特征  

Impact of Climate Warming on the Threshold Temperature in Tibet under Global Climate Change

作　　者：杜军 黄志诚 次旺顿珠 德庆卓嘎[1,2] 周刊社 DU Jun;HUANG Zhi-cheng;Tsewangthondup;Dechendolkar;ZHOU Kan-she(Tibet Institute of Plateau Atmospheric and Environmental Science Research/Tibet Open laboratory of Plateau Atmospheric and Environment,Lhasa 850001,China;Field Science Experiment Base for Comprehensive Observation of Atmospheric Water Cycle in Mêdog,CMA/Mêdog National Climate Observatory,Mêdog 860700;Tibet Meteorological Information and Network Centre,Lhasa 850001;Tibet Autonomous Region Climate Centre,Lhasa 850001)

机构地区：[1]西藏高原大气环境科学研究所/西藏高原大气环境开放实验室,拉萨850001 [2]中国气象局墨脱大气水分循环综合观测野外科学试验基地/墨脱国家气候观象台,墨脱860700 [3]西藏自治区气象信息网络中心,拉萨850001 [4]西藏自治区气候中心,拉萨850001

出　　处：《中国农业气象》2024年第2期111-123,共13页Chinese Journal of Agrometeorology

基　　金：中国气象科学研究院青藏高原与极地气象科学研究所开放课题(ITPP2021K03);西藏自治区科技重点研发计划项目(XZ202001ZY0023N);西藏自治区科技创新基地自主研究项目(XZ2021JR0001G)。

摘　　要：受全球气候变化影响,农牧业生产面临较大风险,研究界限温度时空变化对调整农业种植结构,实现农业可持续发展具有重要意义。利用近40a(1981-2020年)西藏38个气象站点逐日平均气温观测数据,采用线性倾向估计、Person系数、Mann-Kendall、优势分析等方法,分析了气候变暖背景下近40a西藏≥0℃、≥5℃和≥10℃界限温度(初日、终日、持续日数和活动积温)的时空变化特征。结果表明:(1)西藏≥0℃、≥5℃和≥10℃界限温度分布总体上表现为自东南向西北初日推迟、终日提早、持续日数缩短和积温减少的特征,并具有明显的海拔垂直地带性特征。1991-2020年与1981-2010年平均值比较,西藏各站三种积温均增加,以≥10℃积温增幅较大;绝大部分站点初日偏早、终日偏晚、持续日数偏多。(2)近40a西藏≥0℃、≥5℃和≥10℃初日、终日和持续日数的变幅以≥0℃最大,平均每10a初日提早3.2d、终日推迟3.5d、持续日数延长5.4d;积温增幅以≥10℃最大,为86.1℃·d·10a^(-1)。≥0℃、≥5℃持续日数增加是由于初日明显提早造成的,而≥10℃持续日数的增加因终日显著推迟导致。(3)≥0℃界限温度的线性倾向率(LTR),低海拔地区明显大于高海拔地区;≥5℃初日、积温LTR的最大值在低海拔地区,终日、持续日数LTR的最大值在中高海拔地区(3500-4000m);≥10℃初日LTR在中高海拔地区最大,终日、持续日数和积温LTR最大值出现在海拔4000-4500m地区。(4)20世纪80年代≥0℃、≥5℃和≥10℃初日偏晚、终日偏早、持续日数偏短、积温偏低;90年代初日、终日和持续日数正常,积温仍偏低;进入21世纪后,初日偏早、终日偏晚、持续日数增加、积温明显偏高,以21世纪10年代最明显。(5)≥5℃终日突变最早,发生在20世纪90年代初;≥10℃终日突变最晚,在21世纪10年代中期;初日、积温的突变分别出现在20世纪90年代中后期和Under the influence of global climate change,agricultural and livestock production is facing greater risks.It is important to study the spatio-temporal changes of the threshold temperature,in order to provide the informative scientific foundation for adjusting the agricultural cultivation structure to achieve sustainable agricultural development.Based on the daily average temperature observed at 38 meteorological stations over Tibet from 1981 to 2020,the spatial and temporal variation characteristics of≥0℃,≥5℃&≥10℃threshold temperatures[initial date(ID),final date(FD),duration days(DD)and active accumulated temperature(ATT)]over Tibet in the recent 40 years in the context of global warming were analyzed by various statistic methods,including linear tendency estimation,Person coefficient,Mann-Kendall,and dominance analysis.The results showed that:(1)the distribution of≥0℃,≥5℃&≥10℃threshold temperatures in Tibet generally presented the characteristics of delayed ID,earlier FD,shortened DD and reduced ATT from southeast to northwest,without significant vertical zonal characteristics of altitude.Generally,the accumulated temperature of≥0℃,≥5℃&≥10℃decreased by 143.0,136.1,141.5℃·d,respectively,with an increase of 100m in altitude.The average values for all three types of ATT in Tibetan stations have increased respectively in the period of 1991−2020,compared with those in the period of 1981−2020,especially≥10℃.The majority of stations were featured by an earlier ID,a later FD,and a more DD.(2)In the past 40 years,the amplitude of the ID,FD and DD of the threshold temperature in Tibet was the largest at≥0℃,with an average prolonging rate of 5.4d·10y^(-1),caused by an advancing rate of 3.2d·10y^(-1) and a postponing rate of 3.5d·10y^(-1),respectively.The maximum increase of ATT for≥10℃was 86.1℃·d·10y^(-1).The increase of DD for≥0℃and≥5℃was caused by the significantly advanced ID,while the increase of DD for≥10℃can be attributed to the significantly

关 键 词：界限温度 活动积温 初日 终日 变化趋势 年代际变化 气候突变 

分 类 号：S161.2[农业科学—农业气象学]