A Comparison of Auroral Oval Proxies With the Boundaries of the Auroral Electrojets

Walker, S.J.; Laundal, K.M.; Reistad, J.P.; Ohma, A.; Hatch, S.M.; Chisham, G. ORCID: https://orcid.org/0000-0003-1151-5934; Decotte, M.. 2024 A Comparison of Auroral Oval Proxies With the Boundaries of the Auroral Electrojets. Space Weather, 22 (4), e2023SW003689. 19, pp. https://doi.org/10.1029/2023SW003689

Before downloading, please read NORA policies.

Preview

Text (Open Access) ©2024.The Authors. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. Space Weather - 2024 - Walker - A Comparison of Auroral Oval Proxies With the Boundaries of the Auroral Electrojets.pdf - Published Version Available under License Creative Commons Attribution 4.0. Download (3MB) | Preview

Abstract/Summary

The boundaries of the auroral oval and auroral electrojets are an important source of information for understanding the coupling between the solar wind and the near-earth plasma environment. Of these two types of boundaries the auroral electrojet boundaries have received comparatively little attention, and even less attention has been given to the connection between the two. Here we introduce a technique for estimating the electrojet boundaries, and other properties such as total current and peak current, from 1-D latitudinal profiles of the eastward component of equivalent current sheet density. We apply this technique to a preexisting database of such currents along the 105° magnetic meridian, estimated using ground-based magnetometers, producing a total of 11 years of 1-min resolution electrojet boundaries during the period 2000–2020. Using statistics and conjunction events we compare our electrojet boundary data set with an existing electrojet boundary data set, based on Swarm satellite measurements, and auroral oval proxies based on particle precipitation and field-aligned currents. This allows us to validate our data set and investigate the feasibility of an auroral oval proxy based on electrojet boundaries. Through this investigation we find the proton precipitation auroral oval is a closer match with the electrojet boundaries. However, the bimodal nature of the electrojet boundaries as we approach the noon and midnight discontinuities makes an average electrojet oval poorly defined. With this and the direct comparisons differing from the statistics, defining the proton auroral oval from electrojet boundaries across all local and universal times is challenging.

Item Type:	Publication - Article
Digital Object Identifier (DOI):	https://doi.org/10.1029/2023SW003689
ISSN:	1542-7390
Date made live:	08 Apr 2024 10:49 +0 (UTC)
URI:	https://nora.nerc.ac.uk/id/eprint/537231

Actions (login required)

View Item

Document Downloads

More statistics for this item...