This study investigates the feedbacks between an interactive sea surface temperature (SST) and the self‐aggregation of deep convective clouds, using a cloud‐resolving model in nonrotating radiative‐convective equilibrium. The ocean is modeled as one layer slab with a temporally fixed mean but spatially varying temperature. We find that the interactive SST decelerates the aggregation and that the deceleration is larger with a shallower slab, consistent with earlier studies. The surface temperature anomaly in dry regions is positive at first, thus opposing the diverging shallow circulation known to favor self‐aggregation, consistent with the slower aggregation. But surprisingly, the driest columns then have a negative SST anomaly, thus strengthening the diverging shallow circulation and favoring aggregation. This diverging circulation out of dry regions is found to be well correlated with the aggregation speed. It can be linked to a positive surface pressure anomaly (PSFC), itself the consequence of SST anomalies and boundary layer radiative cooling. The latter cools and dries the boundary layer, thus increasing PSFC anomalies through virtual effects and hydrostasy. Sensitivity experiments confirm the key role played by boundary layer radiative cooling in determining PSFC anomalies in dry regions, and thus the shallow diverging circulation and the aggregation speed.

中文翻译：

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对流云的自聚集与海面温度的交互作用


本研究使用非旋转辐射对流平衡中的云解析模型，研究了交互海面温度（SST）与深对流云的自聚集之间的反馈。海洋被建模为具有时间固定平均温度但空间变化温度的一层板。我们发现交互式海表温度会减慢聚集速度，并且板层越浅减速度越大，这与早期的研究一致。干燥地区的地表温度异常首先为正，因此与已知有利于自聚集的发散浅层环流相反，与较慢的聚集一致。但令人惊讶的是，最干燥的柱体出现负海温异常，从而加强了浅层环流的发散并有利于聚集。人们发现，这种离开干燥地区的分流循环与聚集速度密切相关。它可以与正表面压力异常（PSFC）联系起来，其本身是海温异常和边界层辐射冷却的结果。后者冷却并干燥边界层，从而通过虚拟效应和静水作用增加 PSFC 异常。敏感性实验证实了边界层辐射冷却在确定干燥地区 PSFC 异常以及浅层辐散环流和聚集速度中所起的关键作用。