Kelvin-Helmholtz instability and the variation of geomagnetic pulsation activity

Journal Article · Wed Oct 01 04:00:00 UTC 1980 · Geophys. Res. Lett.; (United States)

DOI:https://doi.org/10.1029/GL007i010p00777· OSTI ID:6878681

Lee, L C; Olson, J V

It is shown that the observed local time variation of dayside geomagnetic micropulsations is consistent with the Kelvin-Helmholtz generation mechanism operating at the magnetopause. The variation of the angle between the interplanetary magnetic field and the magnetopause around the magnetosphere causes variations in the magnetosheath magnetic field, which in turn lead to local time variations in micropulsation amplitudes. Morning sector pulsations are expected to be larger than afternoon sector pulsations. Furthermore, large-amplitude pulsations are expected to be more frequently observed when the angle between the interplanetary magnetic field and the solar wind velocity in front of the bow shock is small.

• Research Organization: Geophysical Institute, University of Alaska, Fairbanks, Alaska 99701
• OSTI ID: 6878681
• Journal Information: Geophys. Res. Lett.; (United States), Journal Name: Geophys. Res. Lett.; (United States) Vol. 7:10; ISSN GPRLA
• Country of Publication: United States
• Language: English

Related Subjects

640203* -- Atmospheric Physics-- Magnetospheric Phenomena-- (-1987)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
GEOMAGNETIC FIELD
HELMHOLTZ INSTABILITY
INSTABILITY
INTERPLANETARY MAGNETIC FIELDS
MAGNETIC FIELDS
MAGNETOPAUSE
MAGNETOSHEATH
PLASMA INSTABILITY
PLASMA MACROINSTABILITIES
PULSATIONS
SOLAR ACTIVITY
SOLAR WIND