2007-2009谷年期间高热层大气密度的变化  

Variation of the Upper Atmospheric Density During the Quiet Period of Solar and Geomagnetic Activity(2007—2009)

作　　者：李永平[1,2] 朱光武[1] 秦国泰[1] 

机构地区：[1]中国科学院空间科学与应用研究中心,北京100190 [2]中国科学院大学,北京100049

出　　处：《空间科学学报》2012年第6期829-833,共5页Chinese Journal of Space Science

摘　　要：在第23至第24太阳活动周的峰年之间,太阳活动谷年具有持续时间长,极低F_(10.7)太阳辐射通量(低至65)和超长期的零太阳黑子数记录等特点,因此是观测和研究在这种特殊背景下热层大气变化的极好机会.尤其是能充分理解和掌握在宁静环境下热层大气密度对弱太阳活动和小地磁扰动的响应特性.本文利用高度650 km以上星载大气密度探测器2007—2009年的连续探测数据进行分析,结果表明,在太阳辐射通量F_(10.7)极低值期间,较高热层大气密度对F_(10.7)的起伏具有更显著的响应变化.当F_(10.7)由70降至65时,日均大气密度会有4～5倍的显著降变,远大于通常大气模式中的降变值.同样在F_(10.7)极低值期间,较高热层大气密度对小地磁扰动也具有显著的响应增变,当日K_p指数之和由23增至30时,较高热层大气密度则会有80%～160%的强增变.The period of low solar activity between solar cycle 23 and 24 last a long time, having low F10.7 and long-term sunspot number record. So it is the time to study the change of upper atmospheric density in this quiet solar and geomagnetic activity conditions, especially for study of the response of upper atmosphere to variations in small geomagnetic disturbance and low solar activity. Atmospheric density detector mounted on the satellite near 650 km aims at getting measurement data with the change of geomagnetic and solar flux variability, whose data are available ranging from 2007 to 2009, the results are concluded as follows. Upper atmospheric density obviously responses to the F10.7 variation in condition of low solar activity. When F10.7 decreases from 70 to 65, daily atmospheric density decreases obviously for 4～5 times, which is much larger than the decrease in the model. Upper atmospheric density also obviously responses to the small geomagnetic disturbance.Atmospheric density is increased strongly by 80%～160% when the sum of Kp increases from 23 to 30.

关 键 词：热层大气密度 太阳活动谷年 F10 7 

分 类 号：P401[天文地球—大气物理学与大气环境]