磁暴期间OI 135.6 nm气辉经纬及高度分布的变化特征

Variation in the Longitude-latitude Distribution and Latitude-altitude Distribution of OI 135.6 nm Airglow during Magnetic Storms

利用GUVI探测器观测的OI 135.6 nm气辉辐射数据,研究了2003年10月和11月两次持续时间不同的强磁暴期间气辉辐射强度经纬度分布及纬度–高度分布的变化。结果表明,全球大部分区域内OI 135.6 nm气辉辐射强度在磁暴期间会随着Dst指数的降低而增强,与磁暴的剧烈程度呈现准正相关关系。从纬度上看,气辉辐射强度的增强会由磁静期的磁赤道两侧附近向高纬地区延伸至南北半球50°附近,增幅基本在80%以上,最大可超过200%,且经纬度分布在磁暴期间的变化情况呈现出南北不对称性和纬向不对称性;从高度上看,气辉辐射强度的增强会由磁静期的300~400 km(即电离层F2层高度)扩散至其他高度,特别是在100~200 km(即低热层高度)的部分纬度上会出现相比其他高度更为显著的增强,增幅超过300%;气辉辐射出现增强的时间与磁暴相位基本同步。

Variation in the latitude-longitude distribution and latitude-height distribution of airglow emission intensity during two intense magnetic storms in October and November 2003 were investigated using OI 135.6 nm airglow emission data observed by the GUVI detector.The results show that the intensity of OI 135.6 nm airglow emission in most regions of the world increases with a decrease in the Dst index during the magnetic storms and shows a quasi-positive correlation with the intensity of magnetic storms.Horizontally,the enhancement of airglow emission extends from both sides of the magnetic equator during the magnetic quiescence to the high latitudes to near 50°in the northern and southern hemispheres,and the increase is basically more than 80%,and the maximum can exceed 200%,and the variation of latitude and longitude distribution during the magnetic storms show north-south and latitudinal asymmetry.Vertically,the enhancement of the airglow emission spreads from 300 km to 400 km(i.e.,F2 layer height)to other heights,especially at some latitudes between 100 km to 200 km(i.e.,low thermosphere height),which is more significant than other heights,with an increase of more than 300%;the time of the enhancement of the airglow emission is basically synchronized with the magnetic storm phase.