节点文献
不同太阳活动及地磁条件下的电导率分布变化
Variations of the ionospheric conductivity with different solar activities and geomagnetic conditions
【摘要】 电离层电导率在不同的太阳活动和地磁条件下会发生变化.本文通过中性大气经验模式NRLMSISE00(Neutral Atmosphere Empirical Model2000,简称NRLMSISE00)和电离层经验模式IRI2001(International ReferenceIonosphere2001,简称IRI2001)计算电离层的电子、离子碰撞频率以及电导率,并简要讨论了120 km和300 km高度上的电导率在不同季节、不同太阳活动和地磁指数下的经纬分布.结果显示,电导率的分布与日照密切相关,且随太阳活动的变化而变化.磁暴时电导率随地磁活动的变化相对于随太阳活动的变化要小,在120 km高度,磁暴期间电导率在低纬地区和高纬地区发生不同变化,且Pedersen电导率和Hall电导率变化趋势相反,向两极靠近,电导率变化幅度略有增长;在300 km高度上,磁暴对低纬地区和高纬地区电导率的影响要比120 km处大,Pedersen电导率和Hall电导率变化趋势相同,且越向两极靠近电导率的变化幅度越大.
【Abstract】 The ionospheric conductivity is influenced by solar activities and geomagnetic conditions and has some changes. We calculated the conductivity and the collision frequency between the electrons and ions through models NRLMSISE-00(Neutral Atmosphere Empirical Model-2000) and IRI2001(International Reference Ionosphere-2001).We discussed the seasonal change of the conductivities at 120?km and 300?km and their changes under different solar activities and geomagnetic conditions.The result shows that the conductivity distribution is affected by the sunlight, and changes with solar activities.The geomagnetic disturbance can affect the ionospheric conductivity,but the effect is smaller than that of solar variations.At 120?km,the geomagnetic disturbance leads to the opposite change between Pedersen conductivity and Hall conductivity at different latitudes.At 300?km, the geomagnetic disturbance makes the same trend for Pedersen conductivity and Hall conductivity,and the change extent is bigger than that at 120?km.But the change becomes larger in the direction of pole either at 120?km or 300?km.
【Key words】 Ionospheric conductivity; Collision frequency; Solar activity index; Geomagnetic index;
- 【文献出处】 地球物理学报 ,Chinese Journal of Geophysics , 编辑部邮箱 ,2006年05期
- 【分类号】P352
- 【被引频次】10
- 【下载频次】160