Variations of the peak positions in the longitudinal profile of noon-time equatorial electrojet

Earth, Planets and Space

Vafi Doumbia¹  Zié Tuo¹  Abdel Aziz Kassamba¹  N’Guessan Kouassi¹  Pierdavide Coïsson² 

[1] Laboratoire de Physique de l’Atmosphère et de Mécanique des fluides, UFR-SSMT, Université Felix Houphouet Boigny;Université de Paris, Institut de Physique du Globe de Paris, CNRS;

关键词: Equatorial electrojet;    Longitudinal variation;    Seasonal dependence;   

DOI  :  10.1186/s40623-020-01305-z

来源: DOAJ

【 摘 要 】

Abstract 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.

【 授权许可】

Unknown