标题： 不同行星大气中下落雨滴的物理特性 显示英文标题

标题： The Physics of Falling Raindrops in Diverse Planetary Atmospheres

摘要： 单一雨滴从云层下方下落的演变由流体力学和热力学支配，这些原理从根本上适用于现代地球以外的行星大气。 在这里，我们展示了如何根据雨滴大小计算表征下落雨滴的三个属性——雨滴形状、终端速度和蒸发速率——在任何行星大气中都可以作为函数计算。 我们证明了这些简单且相互关联的特性紧密限制了特定大气中雨滴可能的大小范围，而与生长机制的难以理解无关。 从描述雨滴下落和蒸发的方程出发，我们演示了通过一个新的无量纲数可以很好地捕捉雨滴垂直输送潜热和可凝结物质的能力。 我们的研究结果对降水效率、对流风暴动力学和降雨率具有重要意义，这些性质对于理解行星辐射平衡以及（对于类地行星而言）由降雨驱动的地表侵蚀至关重要。 显示英文摘要

摘要： The evolution of a single raindrop falling below a cloud is governed by fluid dynamics and thermodynamics fundamentally transferable to planetary atmospheres beyond modern Earth's. Here, we show how three properties that characterize falling raindrops -- raindrop shape, terminal velocity, and evaporation rate -- can be calculated as a function of raindrop size in any planetary atmosphere. We demonstrate that these simple, interrelated characteristics tightly bound the possible size range of raindrops in a given atmosphere, independently of poorly understood growth mechanisms. Starting from the equations governing raindrop falling and evaporation, we demonstrate that raindrop ability to vertically transport latent heat and condensible mass can be well captured by a new dimensionless number. Our results have implications for precipitation efficiency, convective storm dynamics, and rainfall rates, which are properties of interest for understanding planetary radiative balance and (in the case of terrestrial planets) rainfall-driven surface erosion.