HR: 11:50h
AN: SA42A-07    [Abstracts]
TI: October 29-31, 2003 geomagnetic storm: geomagnetically induced currents and their relation to problems in the Swedish high-voltage power transmission system
AU: * Pulkkinen, A A
EM: antti.pulkkinen@gsfc.nasa.gov
AF: NASA/GSFC, Code 692, Greenbelt, MD 20771 United States
AU: Lindahl, S
EM: sture.x.lindahl@se.abb.com
AF: Lund Institute of Technology, P.O. Box 118, Lund, 22100 Sweden
AU: Viljanen, A
EM: ari.viljanen@fmi.fi
AF: Finnish Meteorological Institute, Vuorikatu 15 A, P.O. Box 5o3, Helsinki, 00101 Finland
AU: Pirjola, R
EM: risto.pirjola@fmi.fi
AF: Finnish Meteorological Institute, Vuorikatu 15 A, P.O. Box 5o3, Helsinki, 00101 Finland
AB: In October 30, 2003, an ongoing geomagnetic superstorm knocked down a part of the high-voltage power transmission system in southern Sweden operated by the Sydkraft company. The blackout lasted for an hour and left about 50000 people without electricity. The incident was probably the most severe GIC failure observed since the well-known March 1989 Qu\'ebec blackout and thus the problems in a Swedish system deserve a closer look. The geophysical background and the impacts on the Swedish high-voltage power transmission system of the October 29-31, 2003 geomagnetic storm are described in the study at hand. It was seen that athough no serious problems in North-America have been reported, the "three-phase" storm produced exceptionally large geomagnetic activity at the Fennoscandian auroral region. It was also seen that GIC modeled for southern Sweden region using very simplistic methods were able to explain the times of the failures in the Swedish system thus confirming the sources of experienced problems and adding also GIC to the long list of causes of technological impacts of the storm. Though the great diversity of the GIC drivers are addresses in the study, the problems in operating the Swedish system during the exceptionally intense storm of October 29-31, 2003 are attributed geophysically to substorms, SSCs and enhanced ionospheric convection all of which were creating large and complex geoelectric fields capable of driving large GIC. Based on the basic two-fold nature of the failure-related geoelectric field characteristics, a semi-deterministic approach for forecasting GIC-related geomagnetic activity in which average overall activity is supplemented with statistical estimations of the amplitudes of GIC fluctuations is suggested.
DE: 2409 Current systems (2708)
DE: 2788 Storms and substorms
DE: 1515 Geomagnetic induction
SC: SPA-Aeronomy [SA]
MN: 2004 AGU Fall Meeting