Near-Surface Thermodynamic Sensitivities in Simulated Extreme-Rain-Producing Mesoscale Convective Systems
Near-Surface Thermodynamic Sensitivities in Simulated Extreme-Rain-Producing Mesoscale Convective Systems
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DOI：
10.1175/mwr-d-16-0255.1
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发表时间：
2017-05
影响因子：
3.2
通讯作者：
R. Schumacher;J. Peters
中科院分区：
文献类型：
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作者：
R. Schumacher;J. Peters
摘要本文研究了低层大气水汽对暖季中纬度中尺度对流系统（MCS）降水的影响。在一系列半理想化的数值模型实验中，使用从观察到的情况下，从复合环境中收集的初始条件，小的湿度增加被施加到模型的初始条件超过一层600米或1公里深。MCS产生的降水量随着湿度扰动的增加而增加，但降水量的变化与湿度扰动的大小不成比例。最大扰动的实验在最低的1 km处的水汽混合比增加了约2 g kg−1，相当于垂直积分水汽增加了3.4%，并且在这个实验中，区域积分MCS降水比对照增加了近60%。降雨量最大的地点也因..的差异而发生变化。
AbstractThis study investigates the influences of low-level atmospheric water vapor on the precipitation produced by simulated warm-season midlatitude mesoscale convective systems (MCSs). In a series of semi-idealized numerical model experiments using initial conditions gleaned from composite environments from observed cases, small increases in moisture were applied to the model initial conditions over a layer either 600 m or 1 km deep. The precipitation produced by the MCS increased with larger moisture perturbations as expected, but the rainfall changes were disproportionate to the magnitude of the moisture perturbations. The experiment with the largest perturbation had a water vapor mixing ratio increase of approximately 2 g kg−1 over the lowest 1 km, corresponding to a 3.4% increase in vertically integrated water vapor, and the area-integrated MCS precipitation in this experiment increased by nearly 60% over the control. The locations of the heaviest rainfall also changed in response to differences in...