论文标题
对流自聚集是一种冷池驱动的关键现象
Convective Self-Aggregation as a Cold-Pool Driven Critical Phenomenon
论文作者
论文摘要
当对流的自我聚集是在辐射对流平衡中的恒定温度表面上的雷暴群群时。自我种类与Madden-Julian振荡和飓风有关。然而，根据建模选择，数值模拟成功或无法产生自我聚集。自我聚集的常见解释会引起辐射效应，使得将水分集中在子域中。由雨水蒸发引起的冷池之间的相互作用，驱动边界层水分的重组并触发新的上升气流。我们提出了一个通过冷池相互作用聚集的简单模型，假设沉淀单元的局部数量密度$ρ（\ mathbf {r}）$，并且该相互作用用$ρ（\ mathbf {r}）$四倍地缩放。当存在许多细胞时，我们的模型通过限制进一步的细胞产生来模仿全球能量限制。相图显示了连续体和聚合状态之间的连续相变。强烈的冷水池池相互作用产生了均匀的对流阶段，而弱相互作用产生了很少的和独立的细胞。中间相互作用强度的隔离结果。
Convective self-aggregation is when thunderstorm clouds cluster over a constant temperature surface in radiative convective equilibrium. Self-aggregation was implicated in the Madden-Julian Oscillation and hurricanes. Yet, numerical simulations succeed or fail at producing self-aggregation, depending on modeling choices. Common explanations for self-aggregation invoke radiative effects, acting to concentrate moisture in a sub-domain. Interaction between cold pools, caused by rain evaporation, drives reorganization of boundary layer moisture and triggers new updrafts. We propose a simple model for aggregation by cold pool interaction, assuming a local number density $ρ(\mathbf{r})$ of precipitation cells, and that interaction scales quadratically with $ρ(\mathbf{r})$. Our model mimics global energy constraints by limiting further cell production when many cells are present. The phase diagram shows a continuous phase transition between a continuum and an aggregated state. Strong cold pool-cold pool interaction gives a uniform convective phase, while weak interaction yields few and independent cells. Segregation results for intermediate interaction strength.
