Day-to-day Variation of Equatorial Electrojet Controlled by Mid-latitude Sq Current System
Abstract
A dense network of geomagnetic field observations along the 210-degree magnetic meridian during 2000-2002 enabled us to determine daily values of (1) the total current intensity of the equivalent Sq current system Jtotal in kilo-amperes and (2) the distance between the northern and southern foci of the equivalent Sq current system dNS in degrees. It is found that the daily range of the north-south component of the geomagnetic field at Davao (a dip-equatorial station in Philippines) can be well described in this simple form: (Jtotal+76.379)(-0.007dNS+0.8217). The results suggest that day-to-day variation of equatorial electrojet is largely controlled by the intensity and shape of the mid-latitude Sq current system and local effects are often of secondary importance (under 20%).
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2011
- Bibcode:
- 2011AGUFMSA23A1883Y
- Keywords:
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- 2400 IONOSPHERE;
- 2409 IONOSPHERE / Current systems;
- 2411 IONOSPHERE / Electric fields;
- 2415 IONOSPHERE / Equatorial ionosphere