摘要
在台风期间,特别是台风登陆前后,强烈的海气、陆气相互作用会增强低层大气中的湍流活动,并可能导致大气湍流层顶的抬升,这种抬升会改变高层大气结构,从而影响高层大气中的光化学过程,最终造成对电离层的影响,在台风活动抬升了湍流层顶的前提下,利用一个一维电离层物理模型,模拟了日本中纬地区 (45°N,142°E)电离层F2区的响应．模拟结果很好地定性解释了如下观测事实,台风期间,电离层foF2会下降,对给定频率电波的反射面会抬升;同时还表明以上过程会导致hmF2上升,这表明台风期间湍流层顶的抬升可能是台风影响电离层F2区的一种十分有效的机制。
During the period of typhoon, especially when typhoon is approaching the mainland, violent interaction between the wind and the sea surface, the wind and the mainland will greatly strengthen the turbulence in the lower atmosphere, and it will possibly raise the turbopause in altitude. Thus it will change the structure of the earth＇s atmosphere and influence the photochemical process of the upper atmosphere, and consequently influence the ionosphere. Based on the assumption that typhoon will raise the turbopause in altitude, the response of F2 layer of the ionosphere over the middle latitude of Japan （45°N, 142°E） was simulated, by using the one dimensional ionospheric model. The results of the simulation can qualitatively explain the following phenomena very well： f0F2 of the ionosphere will decrease while the reflecting surface in the ionosphere of the radio wave with a certain frequency will increase during the time of typhoon, hmF2 increases due to the raise of turbopause in this simulation. These results suggest that the rising in altitude of turbopause by typhoon is a very reasonable mechanism of typhoon effects on the ionospheric F2 layer.
出处
《空间科学学报》
CAS
CSCD
北大核心
2006年第2期92-97,共6页
Chinese Journal of Space Science
基金
国家自然科学基金面上项目(40374058)
电波环境特性及模化技术国防科技重点实验室项目(51486010103JW0201)共同资助
关键词
台风
湍流层顶
F2区临界频率
F2区峰值高度
Typhoon, Turbopause, Peak density of F2 layer, peak altitude of F2 layer
