The longitude dependence of the dayside F region trough: A detailed model-observation comparison

摘要: The nighttime main F region trough extends into the sunlit afternoon sector. This feature exhibits both a strong magnetic activity dependence and longitude (UT) dependence. Whalen (1987), using International Geophysical Year (IGY) ionosonde data, showed that of these effects are readily extracted from f{sub 0}F{sub 2} observations. In this study authors show effect is same as contained in Utah State University time-dependent ionospheric model. It arises offset geomagnetic axis geographic axis. dependency associated with westward convection also model via empirical magnetospheric one-to-one observational-model agreement unique; to date no other dependent has been simulated systemtically.