• P-ISSN 0974-6846 E-ISSN 0974-5645

Indian Journal of Science and Technology


Indian Journal of Science and Technology

Year: 2021, Volume: 14, Issue: 6, Pages: 541-546

Original Article

Observations of long period HF Doppler oscillations over the dip equatorial ionosphere in the Indian longitudinal sector

Received Date:07 November 2020, Accepted Date:22 December 2021, Published Date:22 February 2021


Background/ Objective: The signatures of long period High Frequency Doppler (HFD) oscillations over a dip equatorial station, Trivandrum (8.33◦N, 77◦E, dip 0.4◦N) in the Indian longitudinal sector have been investigated. Methods: High cadence vertical plasma drift measurements obtained using a Multi frequency HF Doppler Radar over Trivandrum along with ground based magnetometer observations over several latitudes/longitudes have been used to address this very aspect. Findings: It has been observed that long period (~15 min.) oscillations of high latitude origin can instantaneously reflect over the equatorial latitudes in the form of coherent HFD oscillations. The study is very important as it provided a unique opportunity not only to understand various characteristics of HFD oscillations, but also expected to have significant implications in the understanding of equatorial ionospheric variability in context of solar wind-magnetosphere-ionosphere coupling. Novelty: In a complementary point of view, the study also highlights the potential of HF Doppler measurements to capture such transient events originating from interplanetary medium with an unprecedented temporal resolution.

Keywords: HF Doppler radar; equatorial ionosphere; HF Doppler oscillations


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© 2021 Susanth.This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Published By Indian Society for Education and Environment (iSee)


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