2011 SuperDARN Workshop       

Magnetometer and radar study of the ionospheric convection response to sudden changes in the interplanetary magnetic field

R.A.D. Fiori (1,2), D. Boteler (1), A.V. Koustov (2)
(1) Natural Resources Canada, Geomagnetic Observatory, Ottawa, ON, Canada
(2) University of Saskatchewan, Institute for Space and Atmospheric Studies, Saskatoon, SK, Canada

abstract. Both magnetometer and SuperDARN data sets are examined in detail for two separate events to investigate the ionospheric response to the sudden southward turning of the interplanetary magnetic field (IMF). Initially, the IMF perturbation wavefront impinges the magnetosphere near noon, dragging field lines across the front-side magnetosphere into the magnetotail over a period of 5-6 minutes. This translates into a noon-to-midnight progression of the ionospheric onset of the observed magnetic and electric field response to the transition wavefront. Once the southward oriented field lines reach the magnetotail, the ionospheric convection pattern responds simultaneously across the entire high-latitude region. The reverse convection cells established on the dayside due to the period of northward IMF prior to the transition break down, and the foci of the new dawn and duskside convection cells begin a progression from their nightside location toward the dayside which lasts for a periods of 8-10 minutes. These results support an idea that convection reconfiguration associated with a southward turning of the IMF is a two-stage process.

Sakaguchi KaoriNICT Japan