蒸散发过程影响因素众多，潜在蒸散发（ET₀）与气象变量交互作用复杂，亟需揭示ET₀变化对气象变量的响应机理。基于河西走廊及周边21个气象站点气象资料，采用定性定量分析方法，以河西走廊整体及3分区2个空间尺度，揭示ET₀时空变化规律，明确ET₀对各气象因素变化敏感性及贡献。结果表明：（1） 河西走廊及分区ET₀均呈显著波动上升趋势（Z>1.98），线性变化率2.94 mm·a^-1，且黑河分区变化最明显。（2） ET₀由东南向西北递增变化，中东部石羊河分区（1003.78 mm）、黑河分区（1031.30 mm）较小，西部疏勒河分区（1171.89 mm）较大。（3） 河西走廊ET₀对气象因素变化敏感性排序为相对湿度（RH）、日最高气温（T_max）、日照时数（n）、平均风速（u）、日降水量（P），ET₀对RH减少最敏感，对P变化最不敏感。（4） u增大是造成河西走廊ET₀增大的主要原因，其次是RH减少、T_max升高、n增加。（5） 疏勒河分区、黑河分区、石羊河分区ET₀呈增加变化，贡献最大因素分别为T_max（5.13%）、u（8.22%）、T_max（5.97%），贡献最小因素为n。气候因素中的风速和气温变化是河西走廊地区ET₀变化不容忽视的重要影响因素，研究成果对合理规划农田灌溉用水和提高农业水资源利用效率意义重大。

Several factors affect the evapotranspiration process. Potential evapotranspiration (ET₀) interacts with meteorological variables in a complex manner. Therefore, there is an urgent need to determine the response mechanism of ET₀ changes to meteorological variables. Based on meteorological data from 21 meteorological stations in the Hexi Corridor, Gansu Province, China and its surrounding areas, qualitative and quantitative methods were adopted to reveal the spatiotemporal variation of ET₀ and to clarify the sensitivity of ET₀ to changes in various meteorological factors and contributions by taking two spatial scales of the Hexi Corridor as a whole and three subdistricts. The results showed the following: (1) ET₀ in both the Hexi Corridor and the subdistrict showed a significant fluctuating upward trend (Z>1.98), with a linear change rate of 2.94 mm·a^-1, and the most obvious change was observed in the Heihe subdistrict. (2) ET₀ increased from the southeast to northwest. It was smaller in the Shiyang River subdistrict (1003.78 mm) and Heihe subdistrict (1031.30 mm) in the central and eastern parts of the Hexi Corridor, and larger in the Shule River subdistrict (1171.89 mm) in the western part of the Hexi Corridor. (3) The sensitivity of ET₀ to changes in meteorological factors in the Hexi Corridor was ranked as relative humidity (RH), daily maximum temperature (T_max), sunshine duration (n), average wind speed (u), and daily rainfall (P), with ET₀ being the most sensitive to decreases in RH and least sensitive to changes in P. (4) The increase in u was the main cause of the increase in ET₀ in the Hexi Corridor, followed by a decrease in RH, increase in T_max, and increase in n. (5) The ET₀ in the subdistricts of the Shule River, Heihe River, and Shiyang River showed an increasing change, with the factors that contributed the most being T_max (5.13%), u (8.22%), and T_max (5.97%), respectively, and the factor that contributed the least being n. Variations in wind speed and air temperature were important factors that influenced the ET₀ change in the Hexi Corridor. The research results are significant for the rational planning of irrigation water use and improvement of the utilization efficiency of agricultural water resources.