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中国西北干旱区气候变化及其对生态环境的影响是一个十分重要的科学问题,由于有研究发现西北干旱区气候暖湿化现象,这一问题更是受到了各方的高度关注.但至今对于这种暖湿化趋势的进程和尺度特征并不清楚,对生态环境响应气候暖湿化规律的认识也十分有限,对这种暖湿化现象的形成机制和未来长远影响也缺乏深入讨论.本文利用卫星遥感数据、常规观测数据和CMIP6模式集成数据,系统分析了西北干旱区暖湿化的进程和尺度特征及其对生态植被的影响.结果发现,在西北干旱区,近60年来不仅温度和降水均呈显著增加趋势,而且降水增加趋势还在明显加剧.即使考虑了降水和温度综合影响的干燥度指数,变化趋势同样在明显减少,变湿趋势也在不断加剧.从暖湿化的空间分布来看,温度增加趋势在全区域表现一致,而降水增加趋势分布在全区域93.4％的范围,这说明暖湿化趋势在西北干旱区具有空间一致性.从多时间尺度的贡献来看,气候暖湿化以趋势变化和年际变化贡献为主,温度增加的趋势变化贡献大于年际,而降水增加的年际变化贡献大于趋势.当前的气候暖湿化总体有利于生态植被生长,自上世纪80年代以来82.4％的区域植被长势向好发展.从长期趋势看植被指数总体与降水和温度均呈现显著正相关,从年际波动看植被指数对降水的响应更显著,但在不同土地利用类型区域植被对温度和降水的响应特征具有明显差异性.从温度和降水的协同作用看,暖湿匹配的气候类型最有利于植被生长,而冷干匹配的气候类型则相反.西北干旱区气候暖湿化趋势很可能与西风环流和上升运动有所增强有关.预估这种暖湿化趋势在21世纪期间可能还会持续,但会有所减弱,很难改变西北干旱区的基本气候形态.该研究对“一带一路”建设及加快新时代推进西部大开发战略具有重要科学参考意义.“,”The climatic warming and humidification observed in the arid region of Northwest China(ARNC)and their im-pacts on the ecological environment have become an issue of concern.The associated multi-scale characteristics and environmental responses are currently poorly understood.Using data from satellite remote sensing,field observa-tions,and the Coupled Model Intercomparison Project phase 6,this paper systematically analyzes the process and scale characteristics of the climatic warming and humidification in the ARNC and their impacts on ecological vegeta-tion.The results show that not only have temperature and precipitation increased significantly in the ARNC over the past 60 years,but the increasing trend of precipitation is also obviously intensifying.The dryness index,which com-prehensively considers the effects of precipitation and temperature,has clearly decreased,and the trend in humidific-ation has increased.Spatially,the trend of temperature increase has occurred over the entire region,while 93.4％of the region has experienced an increase in precipitation,suggesting a spatially consistent climatic warming and humid-ification throughout the ARNC.Long-term trends and interannual changes in temperature and precipitation dominate the changes in climatic warming and humidification.Compared to interannual variations in temperature,the trend change of temperature contributes more to the overall temperature change.However,the contribution of interannual variations in precipitation is greater than that of the precipitation trend to the overall precipitation change.The cur-rent climatic warming and humidification generally promote the growth of ecological vegetation.Since the 1980s,82.4％of the regional vegetation has thrived.The vegetation index has a significant positive correlation with precipit-ation and temperature.However,it responds more significantly to interannual precipitation variation,although the ve-getation response varies significantly under different types of land use.The warming and humidification of the cli-mate in the ARNC are probably related to intensifications of the westerly wind circulation and ascending air motions.They are expected to continue in the future,although the strength of the changes will probably be insufficient to sig-nificantly change the basic climate pattern in the ARNC.The results of this study provide helpful information for de-cision making related to China's“Belt and Road”development strategies.