大气水汽氢氧稳定同位素直接反映了水在大气中输送、混合和相变等过程的关键信息,通过蒸发皿实验可以模拟大气水汽氢氧稳定同位素组成,但模拟方法的可靠性仍需要实测资料的验证。于2019年9—11月在甘肃兰州进行了蒸发皿实验,对逐日大气水汽氢氧稳定同位素进行模拟,同期利用在线大气水汽氢氧稳定同位素分析仪进行实时监测从而对模拟结果的可靠性进行验证。研究发现：（1） 利用自然蒸发状态下的Craig-Gordon线性阻力模型和水体同位素质量平衡方法模拟得到的大气水汽中δ¹⁸O与直接测量得到的大气水汽中δ¹⁸O之间表现出较好的一致性,均方根误差为4.5‰,平均绝对误差为3.2‰,平均偏差为0.03‰。（2） 大气水汽中δ¹⁸O的模拟残差与相对湿度（R²=0.43）、蒸发剩余比（R²=0.39）和剩余水体同位素值（R²=0.39）都具有一定相关性。（3） 模型对相对湿度的敏感性高,在相对湿度较低时模型误差会增大。在实验末期蒸发剩余比偏低和剩余水体同位素富集的情况下,水汽同位素模拟残差相较于实验前期而言更大。

The stable hydrogen and oxygen isotopes in atmospheric water vapor reflect the key processes of water transport, mixing, and phase change in the atmosphere. The stable isotopic compositions of hydrogen and oxygen in atmospheric water vapor can be simulated using an evaporation pan experiment, but a measurement-based assessment of model reliability is necessary. In this study, an evaporation pan experiment was conducted in Lanzhou, Gansu, from September to November 2019. The daily atmospheric water vapor isotopes were simulated using the Craig-Gordon linear resistance model and the water isotopic mass balance method in a natural evaporative state. Online observations of atmospheric water vapor isotopes were performed using a water vapor isotope analyzer and then the pan-based simulations were verified. The simulated δ ¹⁸O in atmospheric water vapor and the directly measured δ ¹⁸O were in good agreement with a root mean square error of 4.5‰, a mean absolute error of 3.2‰, and a mean bias error of 0.03‰.The residual of simulated δ¹⁸O values were correlated with relative humidity (R²=0.43), remaining ratio (R²=0.39), and the isotopic values of the remaining water bodies (R²=0.39). The model was highly sensitive to relative humidity: lower relative humidity conditionstypically corresponded to a higher error. Under the conditions of low remaining ratio and isotopically enriched remaining water at the end of the evaporation experiment, the simulation residual was much larger than that at the beginning of the experiment.