Evaluation of the contribution of thunderclouds to the electrification of the troposphere and the formation of low altitude electrojet

Abstract:

The geomagnetic data used for this study are obtained from magnetic station of Yaounde, (AMBER Network) located at University of Yaounde 1 in Cameroon (3.87°N, 11.52°E), provide continuous recordings of geomagnetic field since 2009. The H component was used to calculate and analyze the diurnal and monthly Solar quiet variations Sq(H) observed at Yaounde-Cameroon during quiet magnetic days of 2015. The results obtained show that the Sq (H) variation exhibits a significant negative excursion during the night-time. This result leads us to the assumption of the existence of a strong induced current in Yaoundé or another type of current detected by our magnetometer, which could considerably influence the variation of the horizontal component of the magnetic field in Yaoundé. These negative values of the Sq (H) in our station could also be explained by the existence of a type of electrojet, recently discovered by (Mbane Biouele, C. 2015) called tropospheric equatorial electrojet. It is a phenomenon of electrification of the troposphere whose source could be some weather events such as thunderstorms. He reveals in his works the existence of electrons in the troposphere whose circulation in this layer of the atmosphere give birth to the equatorial tropospheric electro-ejector in a low layer denoted (LL-EEJ), could affect to ground-based instruments. Therefore the observations made at our station would be an ideal example. Our work aimed to evaluate the contribution of non-sun sources such as storm clouds to troposphere electrification and the role of the low-level equatorial electrojet (EEJ).