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Updated: Sep 30, 2025
09:55
Surface Renewal: An Advanced Micrometeorological Method for Measuring and Processing Field-Scale Energy Flux Density Data
Published on: December 12, 2013
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Cross-scale energy cascade powered by magnetospheric convection
Aleksandr Y Ukhorskiy1,2, Kareem A Sorathia3, Viacheslav G Merkin3
1SES, Johns Hopkins University Applied Physics Laboratory, Laurel, 20723, USA. ukhorskiy@jhuapl.edu.
Scientific Reports
|March 16, 2022
Summary
Mesoscale dipolarization flows in Earth's magnetosphere drive suprathermal electron instabilities. These instabilities generate kinetic waves and structures, matching observations from the Magnetospheric Multiscale Mission spacecraft.
Area of Science:
- Space Physics
- Plasma Physics
- Magnetospheric Physics
Background:
- Plasma convection in Earth's magnetosphere involves mesoscale flows and magnetic field dipolarizations.
- Spacecraft observations link dipolarization flows to kinetic processes like Alfvén waves and whistler-mode waves.
Purpose of the Study:
- To investigate how mesoscale dipolarization flows generate suprathermal electron instabilities.
- To understand the energy source for observed kinetic waves and structures in the magnetosphere.
Main Methods:
- Utilized three-dimensional test-particle simulations of electron dynamics.
- Coupled simulations one-way to a global magnetospheric model.
- Compared simulation results with in situ observations from the Magnetospheric Multiscale Mission.
Main Results:
- Simulations revealed rapid growth of parallel and perpendicular electron temperature anisotropies.
- These anisotropies formed along the magnetic terrain of dipolarization flows.
- Observed wave activity in spacecraft data aligns with simulation-predicted anisotropies.
Conclusions:
- Mesoscale dipolarization flows are a likely source of free energy for generating magnetospheric plasma waves.
- Electron temperature anisotropies driven by dipolarization flows explain observed wave bursts.
- The study provides a kinetic explanation for wave phenomena in the magnetotail and inner magnetosphere.
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