蒸散是陆面水循环的重要环节，在高寒干旱环境中表现更加复杂。新疆昆仑山北坡位于青藏高原北缘，山区实地气象观测匮乏，对潜在蒸散的认识也有待加强。通过Mann-Kendall检验和经验正交函数分析了1979—2021年新疆昆仑山北坡潜在蒸散的时空变化特征，比较了各流域的变化趋势，并且分析了潜在蒸散与其他气象要素的关系。结果表明：（1） 新疆昆仑山北坡年均潜在蒸散为733.5 mm，从塔里木盆地南缘向南呈现出逐渐减小的空间变化趋势。（2） 1979—2021年潜在蒸散总体呈波动上升趋势，线性变化率为8.7 mm·(10a)^-1，其中2007年以前呈上升趋势，2007年后有下降趋势。（3） 在喀什噶尔河流域、叶尔羌河流域、和田河流域、克里雅河流域、车尔臣河流域以及库木库里盆地6个流域中，车尔臣河流域年均潜在蒸散最高（810.8 mm），其线性变化率也最大（11.4 mm·(10a)^-1），和田河流域和克里雅河流域潜在蒸散的升高趋势相对较小，线性变化率分别为4.9 mm·(10a)^-1和5.0 mm·(10a)^-1。未来仍应加强新疆昆仑山北坡高海拔区域的水文气象观测，以便明确全球变化背景下的水文不确定性。

Evapotranspiration is an important component of the terrestrial water cycle, and is complex in cold and arid environments. The northern slope of the Kunlun Mountains in Xinjiang of China, situated on the northern edge of the Qinghai-Xizang Plateau, lacks a comprehensive understanding of potential evapotranspiration due to the absence of long-term meteorological observations. This study examined the spatiotemporal variations of potential evapotranspiration from 1979 to 2021, especially from a sub-basin perspective, and analyzed the relationship between potential evapotranspiration and other meteorological parameters using the Mann-Kendall test and empirical orthogonal function. The results indicate that: (1) The long-term mean of potential evapotranspiration is 733.5 mm per year, exhibiting a spatial variation trend that decreases gradually from the southern edge of the Tarim Basin towards the south. (2) From 1979 to 2021, the mean potential evapotranspiration has increased by 8.7 mm·(10a)^-1. Before 2007, there was an increasing trend, although a decreasing trend can be seen after 2007. (3) Among the six sub-basins, i.e., the Kaxgar River Basin, the Yarkant River Basin, the Hotan River Basin, the Keriya River Basin, the Qarqan River Basin and the Kumkol Basin, the Qarqan River Basin has the highest annual mean potential evapotranspiration of 810.8 mm and the highest linear trend of 11.4 mm·(10a)^-1. In contrast, the linear trends in the Hotan River Basin (4.9 mm·(10a)^-1) and the Keriya River Basin (5.0 mm·(10a)^-1) are lower. In the future, efforts should be made to enhance hydro-meteorological observations in high-altitude regions of the northern slope of the Kunlun Mountains in Xinjiang to understand hydrological uncertainties under the background of global change.