Impact of Variations in Upper-Level Shear on Simulated Supercells
Impact of Variations in Upper-Level Shear on Simulated Supercells
复制标题
上层剪切力变化对模拟超级电池的影响
DOI：
10.1175/mwr-d-16-0412.1
复制
发表时间：
2016
影响因子：
3.2
通讯作者：
M. Manton
中科院分区：
文献类型：
--
作者：
R. Warren;H. Richter;H. Ramsay;S. Siems;M. Manton
根据有限的观测资料，以前曾有人提出，对流层上部的垂直风切变是控制超级单体形态的关键因素，分别在强、弱和中等切变下，低降水、高降水和经典原型受到青睐。这个想法是，随着上层切变（ULS）的增加，水凝物被更强的风暴相对砧级风从上升气流中输送到更远的地方，限制了它们的生长，从而降低了降水强度。本研究首次尝试通过对6-12 km切变线范围内的超级单体进行理想化模拟来验证这一假设。与预期相反，当ULS震级从0增加到20 m s−1时，地面降水显著增加，外流风也相应加强。这些变化是由于风暴运动的增加，从而导致更强的低空流入，更广泛的上升气流和增强的凝结。更进一步...
AbstractIt has previously been suggested, based on limited observations, that vertical wind shear in the upper troposphere is a key control on supercell morphology, with the low-precipitation, high-precipitation, and classic archetypes favored under strong, weak, and moderate shear, respectively. The idea is that, with increasing upper-level shear (ULS), hydrometeors are transported farther from the updraft by stronger storm-relative anvil-level winds, limiting their growth and thereby reducing precipitation intensity. The present study represents the first attempt to test this hypothesis, using idealized simulations of supercells performed across a range of 6–12-km shear profiles.Contrary to expectations, there is a significant increase in surface precipitation and an associated strengthening of outflow winds as ULS magnitude is increased from 0 to 20 m s−1. These changes result from an increase in storm motion, which drives stronger low-level inflow, a wider updraft, and enhanced condensation. A further...