中国农业气象 ›› 2026, Vol. 47 ›› Issue (10): 1680-1692.doi: 10.3969/j.issn.1000-6362.2026.10.012

• 农业生物气象栏目 • 上一篇    下一篇

1981−2023年西藏极端气温事件时空变化特征

徐薇,甘臣龙,旦增益嘎,陈慧,史继清   

  1. 1. 日喀则市气象局,日喀则 857000;2. 日喀则国家气候观象台,日喀则 857000;3.墨竹工卡县气象局,拉萨 850000;4. 西藏自治区高原生态与农业气象中心,拉萨 850000
  • 收稿日期:2025-09-15 出版日期:2026-10-20 发布日期:2026-10-19
  • 作者简介:徐薇,E-mail:xuwei8338@163.com
  • 基金资助:
    西藏自治区自然科学基金项目(XZ202401ZR0085);日喀则市中央引导地方科技发展资金项目(RKZ2026ZYYD-02);日喀则市重点研发及转化项目(RKZ2026ZD-006);西藏自治区科技计划中央引导地方项目(XZ202602YD0006);西藏自治区科技创新基地建设项目(XZ202401YD0008);拉萨市气象局甘臣龙劳模创新工作室项目

Spatiotemporal Characteristics of Extreme Temperature Events in Xizang from 1981 to 2023

XU Wei, GAN Chen-long, DANZENGYi-ga, CHEN Hui, SHI Ji-qing   

  1. 1.XigazêMeteorological Bureau,Xigazê857000,China; 2.XigazêNational Climate Observatory,Xigazê857000; 3.Maizhokunggar County Meteorological Bureau,Lhasa 850000; 4.Plateau Ecology and Agrometeorology Center, Xizang Autonomous Region, Lhasa 850000
  • Received:2025-09-15 Online:2026-10-20 Published:2026-10-19

摘要:

基于1981−2023年西藏地区38个气象站点逐日最高气温和最低气温数据,选取11个极端气温指数,采用趋势分析、Mann−Kendall突变检验及小波周期分析等方法,研究1981−2023年西藏地区极端气温指数的时空演变特征,明确气候变暖下高原极端气温指数的核心特征、突变节点与周期响应机制,为高原气候变化适应、生态环境保护及防灾减灾政策制定提供科学参考。结果表明:(1)时间上,1981−2023年西藏全区霜冻日数(FD)、冷夜日数(TN10p)和冷持续指数(CSDI)3个冷指数均呈极显著减小趋势(P<0.01),其中FD减幅最大;暖昼日数(TX90p)、暖夜日数(TN90p)和暖持续指数(WSDI)3个暖指数以及最低气温极大值(TXn)、最高气温极小值(TNx)、极端最低气温(TNn)和极端最高气温(TXx)4个极值指数均呈显著增加趋势(P<0.05),以TN90p增幅最大;其他指数即气温日较差(DTR)则呈波动下降趋势。20世纪90年代末西藏地区冷指数(FD、TN10p和CSDI)发生突变后持续下降,暖指数(TX90p、TN90p和WSDI)则在2000年后突破显著性阈值并持续增强。(2)1981−2023年西藏全区11个极端气温指数均存在多尺度周期震荡。其中,冷指数(FD、TN10p和CSDI)在短周期上(30a以下)持续处于低值阶段,而暖指数(TX90p、TN90p和WSDI)、极值指数(TXn、TNx、TNn和TXx)和其他指数(DTR)在相应短周期上多呈持续高值的特征。(3)空间分布上,1981−2023年冷指数(FD、TN10p和CSDI)在拉萨市、山南市、那曲市西部和东部区域呈显著减少趋势,暖指数(TX90p、TN90p和WSDI)近乎西藏全域增加显著,极值指数(TXn、TNx、TNn和TXx)有超80%的区域呈增加趋势,其他指数(DTR)在西藏西部和东部区域表现为减少趋势,呈现明显空间异质性。高海拔区域对气候变化的响应尤为显著,那曲中西部冷指数急剧减少与东北部暖指数剧烈增加形成鲜明空间对比。

关键词: 极端气温指数, Mann?Kendall检验, 小波分析, 西藏

Abstract:

 Based on the daily maximum temperature and minimum temperature data of 38 meteorological stations in Xizang from 1981 to 2023, 11 extreme temperature indices were selected for this study. Methods including trend analysis, the Mann−Kendall mutation test, and wavelet period analysis were employed to systematically investigate the spatiotemporal evolution characteristics of extreme temperature indices in Xizang. The study aimed to clarify the core features, mutation points and periodic response mechanisms of these indices on the plateau under climate warming, providing a scientific reference for climate change adaptation, ecological environmental protection and disaster prevention and mitigation policy formulation in the region. The results showed that: (1) temporally, three cold indices from 1981 to 2023 (frost days FD, cool nights TN10p and cold spell duration index CSDI) across Xizang showed a significant decreasing trend (P<0.01), with FD exhibiting the most pronounced decline. In contrast, warm indices (warm days TX90p, warm nights TN90p and warm spell duration index WSDI) and extreme indices (monthly maximum of daily minimum temperature TXn, monthly minimum of daily maximum temperature TNx, annual minimum of daily minimum temperature TNn and annual maximum of daily maximum temperature TXx) all showed a significant increasing trend (P<0.05), with TN90p showing the most notable increase. Other indices (daily temperature range DTR) exhibited a fluctuating decreasing trend. Mutation analysis revealed that the cold indices underwent significant shifts in the late 1990s and continued to decline thereafter, while the warm indices surpassed the significance threshold after 2000 and continued to intensify. (2) From 1981 to 2023, all 11 extreme temperature indices in Xizang exhibited multi−scale periodic oscillations. The main characteristic was that the cold indices persistently remained in a the low−temperature phase on short−term scales, whereas the warm indices, extreme indices and other indices mostly showed sustained high−temperature features at corresponding short−term scales. (3) Spatially, the cold indices (FD, TN10p and CSDI) from 1981 to 2023 showed a significant decreasing trend in Lhasa, Shannan and the western and eastern parts of Nagqu. The warm indices (TX90p, TN90p and WSDI) exhibited significant increases across almost the entire Xizang. Over 80% of the region displayed an increasing trend for the extreme indices (TXn, TNx, TNn and TXx). At the same time, the DTR index decreased in the western and eastern parts of Xizang, showing distinct spatial heterogeneity. High−altitude regions responded particularly significantly to climate change, with a sharp decrease in the cold indices in the central−western Nagqu region contrasting distinctly with a dramatic increase in the warm indices in the northeastern part of the region, highlighting clear spatial contrasts.

Key words: Extreme temperature index, Mann?Kendall test, Wavelet analysis, Xizang