Idealized simulations of tropical moist convection have revealed that clouds can spontaneously clump together in a process called self-aggregation. This results in a state where a moist cloudy region with intense deep convection is surrounded by extremely dry subsiding air devoid of deep convection. Because of the idealized settings of the simulations where it was discovered, the relevance of self-aggregation to the real world is still debated. Here, we show that self-aggregation feedbacks play a leading-order role in the spontaneous genesis of tropical cyclones in cloud-resolving simulations. Those feedbacks accelerate the cyclogenesis process by a factor of 2, and the feedbacks contributing to the cyclone formation show qualitative and quantitative agreement with the self-aggregation process. Once the cyclone is formed, wind-induced surface heat exchange (WISHE) effects dominate, although we find that self-aggregation feedbacks have a small but nonnegligible contribution to the maintenance of the mature cyclone. Our results suggest that self-aggregation, and the framework developed for its study, can help shed more light into the physical processes leading to cyclogenesis and cyclone intensification. In particular, our results point out the importance of the longwave radiative cooling outside the cyclone.

理想的热带湿对流模拟显示，云团可以在称为自聚集的过程中自发凝聚在一起。这导致具有强烈的深对流的潮湿阴天区域被没有深对流的极其干燥的下沉空气包围。由于发现模拟的理想设置，因此仍在争论自我聚合与现实世界的相关性。在这里，我们展示了在云解析模拟中，自聚集反馈在热带气旋的自发成因中起着主导作用。这些反馈将回旋过程加快了2倍，而导致旋风形成的反馈则显示出与自聚集过程的定性和定量一致性。一旦形成旋风，尽管我们发现自聚集反馈对维持成熟旋风的贡献很小，但微不足道，但风致表面热交换（WISHE）的作用仍占主导地位。我们的结果表明，自聚集及其研究框架可以帮助我们更深入地了解导致旋回和旋风加剧的物理过程。特别是，我们的结果指出了旋风分离器外长波辐射冷却的重要性。