1961—2022年四川省极端气候变化特征及其影响因素

Variation characteristics and influential factors of extreme climate in Sichuan Province from 1961 to 2022

摘要

【目的】研究全球变暖背景下四川省极端气候变化特征，以期减轻极端气候灾害对区域社会经济、农业生产、生态环境等的不良影响。【方法】利用1961—2022年四川省40个气象站点的数据(包括逐日降水量、日最高气温和日最低气温),计算了20个极端气候指数，采用线性趋势法、局部加权回归法、Mann-kendall趋势检验法和皮尔逊相关分析等方法及Arcgis软件分析了四川省川东盆地山地区、川西高山高原区和川西南山地区三个分区极端气候指数的变化趋势及其影响因素。【结果】结果显示：四川省极端气温指数以增暖为主要变化特征，增温趋势显著；极端降水指数以增加为主要变化特征，但变化趋势不显著。【结论】结果表明：(1)1961—2022年四川省极端暖(冷)事件增加(减少),且呈现“低温上升比高温明显、夜间增暖高于白天、暖日数高于冷日数”的特征；空间上，四川省各分区极端气温指数均呈现变暖趋势，且变暖趋势在川西高山高原区、川西南山地区等高海拔区域更显著。(2)四川省降水量以增加为主，降水量的集中程度增大；空间上，川西高山高原区具有湿润化倾向，川东盆地山地区和川西南山地区具有干旱化倾向。极端降水指数表现出“西湿化东干化”的变化特征。(3)大部分极端气候指数与年平均气温、年降水量、经度和海拔呈现显著相关性，而与纬度相关性较低。大气环流因子中大西洋年代际振荡指数(AMO)对四川省极端气候影响最显著。全球变暖背景下极端气候变化特征的分析对四川省防洪抗旱具有重要意义。

Abstract

[Objective] The characteristics of extreme climate change in Sichuan Province under the background of global climate change were studied, with the objective of mitigating the adverse impact on regional social economy, agricultural production, ecological environment and other aspects. [Methods] Based on the meteorological observation datasets including daily precipitation, maximum temperature and minimum temperature at 40 stations in Sichuan Province, 20 different extreme climate indices were calculated. Linear trend analysis, Local weighted regression analysis, Mann-kendall trend test, Pearson correlation analysis and ARCGIS software were used to analyzed the temporal and spatial variations of climate extremes in the mountain area of the eastern Sichuan Basin, the west Sichuan alpine plateau area and the southwest Sichuan mountain area, and the influential factors were discussed. [Results] In Sichuan Province, the extreme temperature indices were characterized by increasing trend, which were significant. The extreme precipitation indices were characterized by wetting, but the trends were not significant. [Conclusion] (1) Extreme warm(cold) events increased(decreased) in Sichuan province from 1961 to 2022, and showed the characteristics of “the rise of low temperature was more obvious than that of high temperature, the warming at night was higher than that of daytime, and the number of warm days were higher than that of cold days”. Spatially, the extreme temperature indices showed increasing trend in all regions of Sichuan province, and the increasing trend was more significant in high altitude areas such as the west Sichuan alpine plateau area and the southwest Sichuan mountain area.(2) In Sichuan province, the precipitation and the concentration of precipitation increased. Spatially, the west Sichuan alpine plateau area had a tendency of wetting, the mountain area of the eastern Sichuan Basin and the southwest Sichuan mountain area had a tendency of drying. The extreme precipitation indices showed a change characteristic of “west wetting and east drying”.(3) Most of the extreme climate indices were significantly correlated with annual mean temperature, annual precipitation, longitude and altitude, while the correlation with latitude was low. The extreme climate change in Sichuan Province mainly influenced by the Atlantic multidecadal oscillation(AMO) and the AMO had the most significant influence on the extreme climate. The analysis of the changing characteristics of extreme climate indices under the background of global warming is of great significance for flood control and drought relief in Sichuan Province.

关键词

四川省 / 极端气温 / 极端降水 / 变化趋势 / 影响因素 / 气候变化 / 时空分布

Key words

Sichuan Province / extreme temperature / extreme precipitation / changing trends / influential factors / climate change / spatiotemporal distribution

基金资助

四川省科技计划资助项目(2022NSFSC1125)

四川省科技计划资助项目(2024NSFSC0832)

中国工程院战略研究与咨询项目“四川季节性干旱区农业绿色高效用水机制与抗旱减灾战略研究”(2023-DFZD-31)

国家自然科学基金项目“南方季节性干旱区滴灌猕猴桃园耗水规律与蒸发蒸腾量模拟研究”(52109060)