On the Mechanisms of Rain Formation in an Idealized Supercell Storm
On the Mechanisms of Rain Formation in an Idealized Supercell Storm
复制标题
理想化超级单体风暴中降雨形成的机制
DOI：
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发表时间：
2015
期刊：
影响因子：
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通讯作者：
H. Morrison
中科院分区：
文献类型：
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作者：
M. Kumjian;Z. Lebo;H. Morrison
摘要深对流风暴通过三种机制产生雨滴：云液滴的凝结和聚合生长（即，暖过程），冰水凝物的融化，以及湿冰雹的脱落。为了研究这些机制的相对重要性和它们对在超级单体风暴表面附近观察到的外来液滴尺寸分布（DSDs）的贡献，使用修改后的莫里森二阶矩微观物理方案对超级单体进行了理想化模拟。修改后的方案包括单独的类别，温暖，脱落，融化的雨。雨来自融化的冰占主导地位的雨团在低层，特别是沿着右前翼降水盾，而脱落雨滴占主导地位的一个地区内的左前翼。暖雨只在低层风暴后翼的上升切变部分占主导地位，但在高空的主要上升气流中占主导地位。低层暖雨团与降水的形成有关。
AbstractDeep convective storms produce raindrops through three mechanisms: condensation and coalescence growth of cloud liquid droplets (i.e., warm processes), melting of ice hydrometeors, and shedding from wet hailstones. To investigate the relative importance of these mechanisms and their contributions to exotic drop size distributions (DSDs) observed near the surface in supercell storms, an idealized simulation of a supercell is performed using a modified version of the Morrison two-moment microphysics scheme. The modified scheme includes separate categories for warm, shed, and melted rain.Rain originating from melting ice dominates the rain mass at low levels, especially along the right forward-flank precipitation shield, whereas shed-rain drops dominate a region within the left forward flank. Warm rain is only dominant in the upshear portion of the rear flank of the storm at low levels, though it dominates the total rain mass within the main updraft aloft. The warm-rain mass at low levels is associat...