Loading...
Please wait, while we are loading the content...
Similar Documents
Yearly variations in the low-latitude topside ionosphere (1999).
| Content Provider | CiteSeerX |
|---|---|
| Author | Bailey, G. J. Su, Y. Z. Oyama, K. -I. |
| Abstract | Abstract. Observations made by the Hinotori satellite have been analysed to determine the yearly variations of the electron density and electron temperature in the low-latitude topside ionosphere. The observations reveal the existence of an equinoctial asymmetry in the topside electron density at low latitudes, i.e. the density is higher at one equinox than at the other. The asymmetry is hemisphere-dependent with the higher electron density occurring at the March equinox in the Northern Hemisphere and at the September equinox in the Southern Hemisphere. The asymmetry becomes stronger with increasing latitude in both hemispheres. The behaviour of the asymmetry has no significant longitu-dinal and magnetic activity variations. A mechanism for the equinoctial asymmetry has been investigated using CTIP (coupled thermosphere ionosphere plasmasphere model). The model results reproduce the observed equinoctial asymmetry and suggest that the asymmetry is caused by the north-south imbalance of the thermo-sphere and ionosphere at the equinoxes due to the slow response of the thermosphere arising from the eects of the global thermospheric circulation. The observations also show that the relationship between the electron density and electron temperature is dierent for daytime and nighttime. During daytime the yearly variation of the electron temperature has negative correlation with the electron density, except at magnetic latitudes lower than 10°. At night, the correlation is positive. Key words: Ionosphere (equatorial ionosphere; iono-sphere-atmosphere interactions; plasma temperature and density) 1 |
| File Format | |
| Publisher Date | 1999-01-01 |
| Access Restriction | Open |
| Subject Keyword | Yearly Variation Electron Density Electron Temperature Low-latitude Topside Ionosphere Equinoctial Asymmetry Magnetic Latitude Low-latitude Topside Magnetic Activity Variation Northern Hemisphere Observed Equinoctial Asymmetry March Equinox Slow Response North-south Imbalance Plasmasphere Model Negative Correlation Global Thermospheric Circulation Topside Electron Density September Equinox Iono-sphere-atmosphere Interaction Model Result Hinotori Satellite Low Latitude Southern Hemisphere |
| Content Type | Text |
| Resource Type | Article |
