摘要
利用常规的地面、高空观测资料、物理量场资料对两次春季冷空气大风过程进行了对比分析。结果表明,中高层的西南急流自西向东影响,不稳定大气层结的加强和发展,是两次大风天气的触发和启动机制,中层冷空气的侵入,有利于强对流大风的发生;揭示了两次过程由于高低层辐合辐散差异而引起的大风区上空两类不同的高低空垂直下沉速度分布特征,指出动量下传作用在地面造成风速的加大主要决定于对流层中低层的下沉速度,这可能也是两次大风过程地面气压梯度接近,而实际风力却差一级的原因。
According to the analysis of windy weather caused by two spring cold fronts Using conventionalground, aerial observation data and the physical field, the results showed that the high-level southwestjet effect from west to east, unstable atmospheric stratification strengthening and development is thetrigger mechanism,the middle intrusion of cold air is conducive to the occurrence of severe convectivewinds;reveals the process of the high and low convergence and divergence caused by differences over thetwo different types of wind zone low altitude vertical sinking velocity distribution, the role that themomentum in the ground caused by the downstream speed is mainly determined by the increase in thelower troposphere sinking speed, which could also be the surface pressure gradient approaching gale, butthe actual difference between wind speed.
出处
《科技通报》
北大核心
2014年第9期38-41,共4页
Bulletin of Science and Technology
关键词
冷空气
大风
物理量场
垂直下沉
cold air
heavy wind
physical field
Vertical sinking
