Power to the magnetosphere: May 4, 1998
Farrugia, C.J.; Burlaga, L.F.; Jordanova, V.K.; Freeman, M.P.; Lawrence, G.; Matsui, H.; Cocheci, C.C.; Arnoldy, R.L.; Scudder, J.D.; Ogilvie, K.W.; Lepping, R.P.. 2003 Power to the magnetosphere: May 4, 1998. Advances in Space Research, 31 (4). 1117-1122. 10.1016/S0273-1177902000891-8Full text not available from this repository.
An extraordinary powering of the magnetosphere by the solar wind occurred in a 3-hour burst early on May 4 when the IMF was very intense and pointed south (≈-35 nT; “erosion phase”). Examining solar wind streams over 3 months, we found that May 4 represented a very fast, hot, non-corotating stream overtaking an interplanetary coronal mass ejection (ICME), thus forming a compound stream. By integrating the “epsilon” parameter over time, we find that the energy deposited in the magnetosphere during the erosion phase on May 4 (of order 7.5 J m−2) was higher to that deposited during the previous 3-day period, itself a very geoeffective interval. We compare the energy and power supply to the magnetosphere on May 4 with 13 other events, mainly ICMEs and magnetic clouds, during the period 1995–2000. Specifically, we examine (a) the total energy input over 3 days, and (b) the average power over a 3-hour period near maximum power of the respective configurations. As regards (a), we find the energy of the May 4 stream to be comparable to that of the strong events observed during the 6-year period. As regards (b), we find May 4 to represent a large fluctuation from the norm, exceeded only by the Bastille Day event (July 15, 2000). The ability to predict a concentration of electromagnetic power and energy such as that in the May 4 fast stream poses a challenge to our ability to predict space weather.
|Programmes:||BAS Programmes > Antarctic Science in the Global Context (2000-2005) > Magnetic Reconnection, Substorms and their Consequences|
|Date made live:||04 Apr 2012 10:42|
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