Kelvin-Helmholtz instability at the magnetopause: energy flux into the magnetosphere

Journal Article · Tue Feb 01 04:00:00 EST 1983 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JA088iA02p00853· OSTI ID:6248569

Pu, Z; Kivelson, M G

A magnetohydrodynamic approach is used to investigate how compressional linearly unstable Kelvin-Helmholtz surface waves on the magnetopause extract energy from the velocity shear and radiate that energy away from the boundary in the separate rest frames of the plasmas on the two sides. On the magnetospheric side, the energy transport velocity normal to the magnetopause may become comparable with the Alfven speed. The energy flux, for typical conditions on the dayside magnetopause, is found to be approx. =10/sup -3/ ergs/cm/sup 2/ s, and the total energy flux over the unstable region on the dayside magnetopause is estimated to be approx. =10/sup 17/ ergs/s in magnetic quiet times, or > or approx. =10/sup 18/ ergs/s in disturbed times. The discussion of energy input into the magnetosphere illuminates how surface waves on the magnetopause provide the power to drive resonant regions within the magnetosphere at large distances from the boundary.

• Research Organization: Department of Earth and Space Sciences, and Institute of Geophysics and Planetary Physics, University of California, Los Angeles, California 90024
• OSTI ID: 6248569
• Journal Information: J. Geophys. Res.; (United States), Journal Name: J. Geophys. Res.; (United States) Vol. 88:A2; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640203* -- Atmospheric Physics-- Magnetospheric Phenomena-- (-1987)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ALFVEN WAVES
EARTH ATMOSPHERE
ENERGY TRANSFER
FLUID MECHANICS
HELMHOLTZ INSTABILITY
HYDRODYNAMICS
HYDROMAGNETIC WAVES
INSTABILITY
MAGNETOHYDRODYNAMICS
MAGNETOPAUSE
MAGNETOSHEATH
MAGNETOSPHERE
MECHANICS
PLASMA INSTABILITY
PLASMA MACROINSTABILITIES
PLASMA WAVES
SHEAR
WAVE PROPAGATION