Stratocumulus cloud top entrainment has a significant effect on cloud properties, but there are few observations quantifying its impact. Using explicit 0‐D parcel model simulations, initialized with below‐cloud in situ measurements, and validated with in situ measurements of cloud properties, the shortwave cloud radiative forcing (SWCF) was reduced by up to 100 W m⁻² by cloud top entrainment in the Southern Ocean. The impact of entrainment‐corrected SWCF is between 2 and 20 times that of changes in the aerosol particle concentration or updraft at cloud base. The variability in entrainment‐corrected SWCF accounts for up to 50 W m⁻² uncertainty in estimating cloud forcing. Measurements necessary for estimating the impact of entrainment on cloud properties can be constrained from existing airborne platforms and provide a first‐order approximation for cloud radiative properties of nonprecipitating stratocumulus clouds. These measurement‐derived estimates of entrainment can be used to validate and improve parameterizations of entrainment in Global Climate Models.

中文翻译：

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减少云顶夹带的测量约束，以减少南大洋非降水性层积云短波辐射强迫的不确定性

层积云顶夹带对云的性质有显着影响，但很少有观测可量化其影响。使用显式的0-D包裹模型模拟，通过云下原位测量进行初始化并通过云特性进行原位测量进行验证，通过云顶夹带将短波云辐射强迫（SWCF）降低多达100 W m ^-2在南大洋。夹带校正后的SWCF的影响是云底气溶胶颗粒浓度或上升气流变化的2到20倍。夹带校正的SWCF的变异性高达50 W m ^-2估算云强迫的不确定性。估计夹带对云特性的影响所需的测量可以从现有的机载平台上进行约束，并且可以为非降水平积云的云辐射特性提供一阶​​近似值。这些源自测量的夹带估计可用于验证和改进全球气候模型中夹带的参数化。