Kelvin–Helmholtz Instability at the Magnetopause: A Parameter Space Study with MAGE
The Kelvin–Helmholtz instability (KHI) occurs in regions of strong velocity shear in fluids and magnetized plasmas. At Earth’s magnetopause, KHI is routinely observed by various spacecraft missions. Chandrasekhar (1961) demonstrated that KHI growth is expected when the velocity shear is sufficiently strong to overcome magnetic stabilization, thereby contributing to the transport of momentum and energy from the solar wind into Earth’s magnetosphere. Kavosi and Raeder (2015) showed, using THEMIS observations, that Kelvin–Helmholtz waves occur at the magnetopause approximately 19% of the time. Although KHI is a common occurrence at the magnetopause, satellite observations alone are insufficient to fully understand its onset and coupling with solar wind conditions.
In this study, we investigate the parameter space governing KHI growth using MAGE simulations of the magnetosphere under strictly northward and southward interplanetary magnetic field (IMF) conditions. We analyze the occurrence and dawn–dusk asymmetry of KHI at the magnetopause. Our results show that KHI is suppressed on the dusk flank and occurs more frequently on the dawn flank. We present a preliminary analysis suggesting that this asymmetry is likely due to stabilization associated with the plasmaspheric plume on the dusk side, along with a statistical analysis of KH occurrence within our parameter space.
Oshina Jagtap is a Newkirk fellow and PhD student at University of Texas at Arlington. Her research area is magnetospheric plasma physics. Her current work uses MAGE simulations to study Kelvin-Helmholtz Instability at magnetopause of Earth.