中文摘要：

利用DMSP F13卫星离子漂移速度测量数据和Wind卫星行星际磁场测量数据,对极区顶部电离层离子整体上行进行研究,主要考察平静期和磁暴期离子上行强度,以及不同行星际磁场方向和季节对离子上行的影响。研究发现,无论是南半球还是北半球,磁暴期的上行发生率都超过平静期;无论磁暴期还是平静期,南半球在北向行星际磁场时上行发生率高于南向行星际磁场、北半球在南向行星际磁场时上行发生率高于北向行星际磁场,且该结论在磁暴期比平静期更为明显;南半球平静期在北向行星际磁场和南向行星际磁场时冬季的上行发生率都远高于夏季,超过2倍,北半球平静期在北向行星际磁场和南向行星际磁场时夏季的上行发生率高于冬季。

英文摘要：

Based on a large dataset of ion drift velocity measurements onboard the DMSP F13 satellite and interplanetary magnetic field measurements onboard the Wind satellite,a study is made of the plasma bulk upward flowing ions in the topside polar ionosphere,with an emphasis on the quiet-time and storm-time changes in the distribution of upward occurrence and the impact of different interplanetary magnetic fields and seasons on the upward occurrence.The results show that the storm-time occurrence possibility of upward events is higher than that during quiet times in both the Southern Hemisphere and Northern Hemisphere.In the Southern Hemisphere and north of the interplanetary magnetic field,the possibility of upward events is higher than south of the interplanetary magnetic field;and in the Northern Hemisphere and south of the interplanetary magnetic field,the possibility of upward events is higher than north of the interplanetary magnetic field.These conclusions are more obvious in the magnetic storm period than the quiet period.Seasonally,in the Southern Hemisphere,upward events in winter are twice as likely as in summer,and this is the case during quiet times and north of the interplanetary magnetic field as well as during storm times and south of the interplanetary magnetic field.Mean while,in the Northern Hemisphere,the possibility of upward events in summer is greater than in winter,and this is true for quiet times north and south of the interplanetary magnetic field.Large amounts of energetic particles are propagated by the dayside soft precipitating particles （1 keV for ions and 100 eV for electrons） and night side auroral sub-storm particle in jections.This causes the moment transfer and heating of the cold plasma in the polar cap area by fractional heating and the ambipolar diffusion topside the F region of the ionosphere.At the same time,plasma waves,such as extremely low-frequency broadband waves,and ion cyclotron and lower hybrid waves,are involved by the convective velocity shear and plasma instability