In this study, the seasonal variations of the EEJ longitudinal profiles were examined based on the full CHAMP satellite magnetic measurements from 2001 to 2010. A total of 7537 satellite noon-time passes across the magnetic dip-equator were analyzed. On the average, the EEJ exhibits the wave-four longitudinal pattern with four maxima located, respectively, around 170° W, 80° W, 10° W and 100° E longitudes. However, a detailed analysis of the monthly averages yielded the classification of the longitudinal profiles in two types. Profiles with three main maxima located, respectively, around 150° W, 0° and 120° E, were observed in December solstice (D) of the Lloyd seasons. In addition, a secondary maximum observed near 90° W in November, December and January, reinforces from March to October to establish the wave-four patterns of the EEJ longitudinal variation. These wave-four patterns were divided into two groups: a group of transition which includes equinox months March, April and October and May in the June solstice; and another group of well-established wave-four pattern which covers June, July, August of the June solstice and the month of September in September equinox. For the first time, the motions in the course of seasons of various maxima of the EEJ noon-time longitudinal profiles have been clearly highlighted.

中文翻译：

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正午时赤道电射流纵向剖面峰值位置的变化

在这项研究中，基于 2001 年至 2010 年的完整 CHAMP 卫星磁测量检查了 EEJ 纵向剖面的季节性变化。总共分析了 7537 颗卫星中午时间穿过磁倾角赤道。平均而言，EEJ 表现出四波纵向模式，其中四个最大值分别位于西经 170°、西经 80°、西经 10°和东经 100°附近。然而，对月平均值的详细分析产生了两种类型的纵向剖面分类。在劳埃德季节的十二月至日 (D) 观察到三个主要最大值的剖面，分别位于西经 150°、东经 0°和东经 120°附近。此外，在 11 月、12 月和 1 月，在 90° W 附近观测到一个次要最大值，从 3 月到 10 月加强以建立 EEJ 纵向变化的四波模式。这些第四波模式被分为两组：一组过渡，包括春分三月、四月和十月以及六月至日的五月；以及另一组完善的四浪模式，涵盖了六月至日的六月、七月、八月和九月春分的九月。首次清楚地突出了EEJ正午纵向剖面各最大值的季节变化过程。六月至八月和九月的九月春分。首次清楚地突出了EEJ正午纵向剖面各最大值的季节变化过程。六月至八月和九月春分的九月。首次清楚地突出了EEJ正午纵向剖面各最大值的季节变化过程。