The high‐cloud amount responses to sea surface temperature (SST) changes were investigated based on simulations with radiative‐convective equilibrium configuration using a high‐resolution nonhydrostatic icosahedral atmospheric model. The radiative‐convective equilibrium was calculated using a nonrotating sphere with Earth radius and a 14‐km horizontal mesh with uniform SSTs of 300 and 304 K. Two types of cloud microphysics schemes (single‐ and double‐moment bulk schemes) and two types of vertical layer configurations (38 and 78 layers) were tested. The radiatively driven circulation weakens with increasing SST in all simulation pairs due to the increase in the static stability, as suggested in previous studies. In contrast, the high‐cloud amount increases in three simulation pairs and decreases in one pair. These indicate that the weakening of radiatively driven circulation with increasing SST does not always accompany the high‐cloud amount decrease. We determined that the tropopause layer was wet (dry) in simulations that showed positive (negative) high‐cloud cover responses. The radiatively driven upward moisture transport just below the wet tropopause layer increases with increasing SST in the simulation pairs with positive high‐cloud amount responses, and this causes the supply of ice condensate to the lower layer through the sedimentation process, while this feedback was not observed in the simulation pair with the negative response. These indicate that the high‐cloud cover response depends on the occurrence of the feedback and there is a feedback threshold among the variety of simulations. And furthermore, these speculate that whether the feedback mechanism is effective or not has the large impact on high‐cloud responses in the real atmosphere.

中文翻译：

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使用高分辨率全球非静水模型的辐射-对流平衡实验中，云微观物理学对云对海面温度的响应中的作用

使用高分辨率非静水二十面体大气模型，基于辐射-对流平衡构型的模拟，研究了对海面温度（SST）变化的高云量响应。辐射-对流平衡是使用地球半径为半径的非旋转球体以及具有300和304 K均匀SST的14 km水平网格计算的。两种类型的云微物理方案（单矩和双矩体方案）和两种类型的测试垂直层配置（38和78层）。如先前的研究所述，由于静态稳定性的提高，在所有模拟对中，辐射驱动的循环都随着SST的增加而减弱。相反，高云量在三个模拟对中增加而在一对中减少。这些表明随着SST的增加，辐射驱动循环的减弱并不总是伴随着高云量的减少。我们确定对流层顶层在显示正（负）高云层响应的模拟中是湿（干）层。在具有正高云量响应的模拟对中，正对湿对流层顶层下方辐射驱动的向上水分传输随SST的增加而增加，这导致通过沉降过程将冰凝结物供应至下层，而该反馈并未在模拟对中观察到负响应。这些表明高云覆盖响应取决于反馈的发生，并且在各种模拟中都有一个反馈阈值。而且，