Journal cover Journal topic
Annales Geophysicae An open-access journal of the European Geosciences Union
Ann. Geophys., 29, 1305-1315, 2011
© Author(s) 2011. This work is distributed under
the Creative Commons Attribution 3.0 License.
22 Jul 2011
IMF By effects in the plasma flow at the polar cap boundary
R. Lukianova1,2 and A. Kozlovsky3 1Arctic and Antarctic Research Institute, St. Petersburg, Bering Str. 38, 199397, Russia
2Space Research Institute, Moscow, Profsoyuznaya Str. 84/32, 199397, Russia
3Sodankylä Geophysical Observatory of the University of Oulu, P.O. Box 3000, 90014, Finland
Abstract. We used the dataset obtained from the EISCAT Svalbard Radar during 2000–2008 to study statistically the ionospheric convection in a vicinity of the polar cap boundary as related to IMF By conditions separately for northward and southward IMF. The effect of IMF By is manifested in the intensity and direction of the azimuthal component of ionospheric flow. The most significant effect is observed on the day and night sides whereas on dawn and dusk the effect is essentially less prominent. However, there is an asymmetry with respect to the noon-midnight meridian. On the day side the intensity of By-related azimuthal flow is maximal exactly at noon, whereas on the night side the maximum is shifted toward the post-midnight hours (~03:00 MLT). On the dusk side the relative reduction of the azimuthal flow is much larger than that on the dawn side. Overall, the magnetospheric response to IMF By seems to be stronger in the 00:00–12:00 MLT sector compared to the 12:00–24:00 MLTs. Quantitative characteristics of the IMF By effect are presented and partly explained by the magnetospheric electric fields generated due to the solar wind and also by the position of open-closed boundary for different IMF orientation.

Citation: Lukianova, R. and Kozlovsky, A.: IMF By effects in the plasma flow at the polar cap boundary, Ann. Geophys., 29, 1305-1315,, 2011.
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