Abstract
The daytime equatorial electrojet is a narrow band of enhanced eastward current flowing in the 100–120 km altitude region within ±2° latitude of the dip equator. A unique way of determining the daytime strength of the electrojet is to observe the difference in the magnitudes of the Horizontal (H) component between a magnetometer placed directly on the magnetic equator and one displaced 6–9° away. The difference between these measured H values provides a direct measure of the daytime electrojet current, and in turn, the magnitude of the vertical E×B drift velocity in the F region ionosphere. This paper emphasizes two major topics related to the title: (1) Describes and summarizes the techniques developed for obtaining the daytime, E×B drift velocities from ground-based magnetometer observations, and (2) Describes and summarizes the equatorial, ionospheric physical transport mechanisms that have been addressed using these techniques.
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Acknowledgements
We thank Dr. Koki Chau, Director of the Jicamarca Radio Observatory, for providing the Jicamarca and Piura magnetometer data. The Jicamarca Radio Observatory is a facility of the Instituto Geofisico del Peru, Ministry of Education, and is operated with support from the NSF Cooperative agreement ATM-o432565. We also thank Prof. Kiyo Yumoto, Dept. of Earth and Planetary Sciences, Kyushu University, Fukuoka, Japan for supplying the Davao and Muntinlupa magnetometer observations.
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Anderson, D. (2011). Daytime Vertical E×B Drift Velocities Inferred from Ground-Based Equatorial Magnetometer Observations. In: Abdu, M., Pancheva, D. (eds) Aeronomy of the Earth's Atmosphere and Ionosphere. IAGA Special Sopron Book Series, vol 2. Springer, Dordrecht. https://doi.org/10.1007/978-94-007-0326-1_14
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DOI: https://doi.org/10.1007/978-94-007-0326-1_14
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