楚雄州近65年来最低气温变化特征与突变分析

Characteristics and Mutation Analysis of Minimum Temperature Changes in Chuxiong Prefecture over the Past 65 Years

摘要: 为揭示楚雄州最低气温长期变化规律及区域差异，本研究基于该地区10个国家气象观测站1960~2024年逐日最低气温数据，采用Mann-Kendall趋势检验、Sen斜率估计、Pettitt突变检验等方法，分析年、季尺度平均最低气温时空变化特征。结果显示，年尺度上，除元谋县呈不显著下降外，其余9县市年平均最低气温均显著上升(通过a = 0.05或a = 0.01检验)，上升站点平均增温速率0.25℃/10 a，楚雄市增温最快(Sen斜率0.61℃/10 a)。季节尺度上，增温呈“冬春强、夏秋弱”特征，冬季增温速率最高(0.36℃/10 a)，夏季最低(0.16℃/10 a)；空间上，禄丰市夏季与元谋县春、冬季降温，其余地区均升温。年代际变化显示，2010年后全区增温加速，2020~2024年达峰值；部分县市年、季尺度存在气候突变点。本研究揭示了楚雄州最低气温变化的时空异质性，对当地农业规划与气候适应策略制定具有参考价值。

Abstract: To investigate the long-term variation patterns and regional disparities of minimum temperature in Chuxiong Prefecture, this study analyzed the spatiotemporal characteristics of annual and seasonal mean minimum temperatures using daily data from 10 national meteorological stations during 1960~2024, incorporating the Mann-Kendall test, Sen’s slope estimation, and Pettitt mutation test. Results indicated that annual mean minimum temperatures increased significantly (α = 0.05/0.01) in 9 counties/cities, with an average warming rate of 0.25˚C/decade and the highest rate in Chuxiong City (0.61˚C/decade), whereas an insignificant decrease was observed in Yuanmou County. Seasonally, warming was more pronounced in winter-spring (peak: 0.36˚C/decade) than in summer-autumn (minimum: 0.16˚C/decade). Spatially, cooling occurred in Lufeng City (summer) and Yuanmou County (spring/winter), while warming prevailed elsewhere. Warming accelerated after 2010, peaking in 2020~2024, with climate mutation points detected at annual and seasonal scales in some regions. This study reveals the spatiotemporal heterogeneity of minimum temperature changes in Chuxiong Prefecture, offering valuable references for local agricultural planning and the formulation of climate adaptation strategies.