Source: adapted from T.S. Molinski, W.E. Feero and B.L. Damsky (2000) “Shielding grids from solar storms”, IEEE Spectrum.
The geomagnetic north pole is located approximately at 80 degrees of latitude on Ellesmere Island in Canada. Because of the structure of the earth’s electromagnetic field, a geomagnetic storm creates field disturbances that impact various power systems such as electric grids, global positioning systems, and telecommunications. The above map represents the probability of a significant geomagnetic storm with a pattern shaped like concentric circles from the geomagnetic north. The highest risk area is roughly between 50 and 65 degrees north over the North American continent and between 60 and 75 degrees north over the European continent.
The higher risk areas also cover both the transatlantic and transpacific great circle air routes, which in case of a serious geomagnetic storm, could expose passengers to high radiation levels and may disrupt the aircraft navigation system. Still, the main risk concerns electric distribution systems that are ill-prepared to deal with large-scale events.
In 1989 a severe geomagnetic storm caused the collapse of Quebec’s power grid, leaving 6 million people without power for 9 hours. An important reason why this Canadian province was hit is that a large share of its electricity is generated by hydroelectric plants in Northern Quebec (mostly around James Bay), which is at the threshold of the highest electromagnetic storm probability area.