Solar wind control of magnetosheath jet formation and propagation to the magnetopause
File(s)Lamoury_JGR_2021_submission2.pdf (1.48 MB)
Accepted version
Author(s)
LaMoury, Adrian T
Hietala, Heli
Plaschke, Ferdinand
Vuorinen, Laura
Eastwood, Jonathan P
Type
Journal Article
Abstract
Magnetosheath jets are localized high-dynamic pressure pulses originating at Earth's bow shock and propagating earthward through the magnetosheath. Jets can influence magnetospheric dynamics upon impacting the magnetopause; however, many jets dissipate before reaching it. In this study we present a database of 13,096 jets observed by the Time History of Events and Macroscale Interactions during Substorms spacecraft from 2008 to 2018, spanning a solar cycle. Each jet is associated with upstream solar wind conditions from OMNI. We statistically examine how solar wind conditions control the likelihood of jets forming at the shock, and the conditions favorable for jets to propagate through the magnetosheath and reach the magnetopause. We see that, for each solar wind quantity, these two effects are separate, but when combined, we find that jets are over 17 times more likely to reach and potentially impact the magnetopause when the interplanetary magnetic field (IMF) orientation is at a low cone angle, and approximately 8 times more likely during high speed solar wind. Low IMF magnitude, high Alfvén Mach number, and low density approximately double the number of jets at the magnetopause, while urn:x-wiley:21699380:media:jgra56749:jgra56749-math-0001 and dynamic pressure display no net effect. Due to the strong dependence on wind speed, we infer that jet impact rates may be solar cycle dependent as well as vary during solar wind transients. This is an important step towards forecasting the magnetospheric effects of magnetosheath jets, as it allows for predictions of jet impact rates based on measurements of the upstream solar wind.
Date Issued
2021-09
Date Acceptance
2021-09-01
Citation
Journal of Geophysical Research: Space Physics, 2021, 126 (9), pp.1-15
ISSN
2169-9380
Publisher
American Geophysical Union (AGU)
Start Page
1
End Page
15
Journal / Book Title
Journal of Geophysical Research: Space Physics
Volume
126
Issue
9
Copyright Statement
© 2021. American Geophysical Union. All Rights Reserved. This is the accepted version of the following article: LaMoury, A. T., Hietala, H., Plaschke, F., Vuorinen, L., & Eastwood, J. P. (2021). Solar wind control of magnetosheath jet formation and propagation to the magnetopause. Journal of Geophysical Research: Space Physics, 126, e2021JA029592, which has been published in final form at https://doi.org/10.1029/2021JA029592
Sponsor
Science and Technology Facilities Council (STFC)
Identifier
https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2021JA029592
Grant Number
ST/S000364/1
Subjects
0201 Astronomical and Space Sciences
0401 Atmospheric Sciences
Publication Status
Published
Date Publish Online
2021-09-22