Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.13/25237

OpenURL Link
Title
North-south asymmetry of the amplitude of high-latitude Pc 3-5 pulsations: Observations at conjugate stations
Author/Creator
Obana, Y.;  Yoshikawa, A.;  Olson, J. V.;  Morris, R. J.;  Fraser, Brian J.;  Yumoto, K.
Description
The north-south asymmetry of the amplitude of ULF pulsations in the Pc 3-5 band is studied using magnetic field data from the magnetically conjugate stations at L similar to 5.4: Kotzebue (KOT) in the northern hemisphere and Macquarie Island (MCQ) in the southern hemisphere. We obtained the following results for the northward (H) component of magnetic pulsations: (1) The north to south power ratio shows a maximum in the northern winter and a minimum in the northern summer. This "seasonal variation'' is stronger at higher frequencies (Pc 3 and Pc 4 frequencies). (2) The north to south power ratio for the Pc 4 and Pc 5 frequency band is basically greater than 1.0 for all seasons. This "positive offset'' is stronger at lower frequencies. The "seasonal variation'' implies that the magnetohydrodynamic (MHD) waves incident from the magnetosphere are more strongly shielded when the ionospheric conductivity is higher. The "positive offset'' may result from the difference of the background magnetic field intensity between KOT and MCQ.
Relation
Journal of Geophysical Research-Space Physics Vol. 110, no. A10, p. A10214
Date
2005
Publisher
American Geophysical Union
Keyword(s)
finite ionosphere conductivities;  period magnetic pulsations;  field;  line oscillations;  divergent hall-current;  standing alfven waves;  pc;  3,4 pulsations;  geomagnetic-pulsations;  ulf waves;  hydromagnetic-waves;  magnetometer-array
Resource Type
journal article
Identifier
http://hdl.handle.net/1959.13/25237
Identifier
ISSN:0196-6928
Language
eng
Reviewed
Reviewed
25 Visitors 26 Hits 0 Downloads
Save/E-mail Citation
Citation Format
E-mail Address
Subject
"Journal of Geophysical Research-Space Physics"
 
OR