在强地磁活动期间热层大气成份和密度的变化

CHANGE OF THE THERMOSPHERECOMPOSITION AND DENSITY DURING SEVEREGEOMAGNETIC ACTIVITIES

选用了１９７４－０７－０６、１９８２－０３－０２和１９８２－０９－０６Ｈ次强地磁活动时的Ａｐ值，由ＡＥ－Ｃ和ＤＥ－Ｂ卫星所测得的热层成份数据，进行统计分析，结果表明：在强地磁活动期间，热层大气密度涨落变化十分清晰，涨幅随高度增高而增大，高度６００ｋｍ附近涨幅可超过４倍；热层大气成份中Ｎ２的数密度涨幅最大，而原子氧的丰度在强地磁活动期间明显地下降．

In this papers the AP values for three geomagnetic activities of Jul. 6, 1974,Mar. 2, 1982 and Sept. 6, 1982, and thermospheric composition data from AEC and DE-B are used to search the change of the thermospheric composition anddensity during severe geomagnetic activities. The results show that the fluctuationof thermospheric density is very clear during severe geomagnetic activities. Andthe magnitude of this change increases as the altitude increases. At near 600km,the change can be four times of the original values, the change of N2 density is thelajrgest in all of the thermospheric compositions; while the abundance of O (No/Nall)decreases notably during severe geomagnetic activities.