Modeling of the equatorial electrojet during geomagnetic quiet periods
By utilizing the Equatorial Electrojet(EEJ)data observed by the Swarm-A satellite in the past decade from November 2013 to February 2023,an empirical model of EEJ is constructed.In this model the peak densities of EEJ for quiet geomagnetic activity(Kp ≤3)are characterized as a function of longitude,local time,season,solar radiation flux and moon phase.By taking advantage of our model,we can obtain the EEJ value corresponding to the EEJ value observed by Swarm-A.Statistically the correlation coefficient between the EEJ values calculated by our model and measured by Swarm-A satellite is about 0.76,and the average absolute error(the root mean square error)between the aforementioned two dataset is about 20.91(27.32)mA • m-1.It is indicated that the model can characterize the typical features of the EEJ observed by Swarm-A during the period from November 2013 to February 2023.These typical features include:(1)The modeled EEJ increases with the increasing of solar radiation flux;(2)EEJ has an obvious diurnal variation,reaching the maximum value at noon and usually presenting westward EEJ around sunrise;(3)EEJ shows a prominent longitudinal wave-like pattern;(4)the EEJ exhibits an obvious dependence on season,achieving the crests during equinox seasons and valleys for solstice seasons;(5)EEJ near noon has a maximum value for the new moon and full moon periods.In order to further verify the performance of our model,we validated it by using the EEJ current density data observed by Swarm-B from November 2013 to February 2023.And the results show that the model can reproduce well the variation of EEJ observed by Swarm-B.
Equatorial ElectrojetSwarm constellationEmpirical model
万方数据
维普
