Communication Division

Office of Critical Infrastructure Protection and Emergency Preparedness

Ottawa, Ontario, Canada

Date: 30 April 2002

Threat Analysis Number: TA02-001

This report has been compiled to assist Canadian critical infrastructure
(CI) owners and operators with their emergency management planning by
discussing how geomagnetic storms can impact CI and by addressing ways
in which industry can mitigate the impacts of these potentially
dangerous storms. This report also illustrated some of the proactive
practices that Canadian industry has implemented to avoid prolonged
negative effects from geomagnetic storms. This document was derived
primarily from open sources and draws on a variety of public and
private information current to 29 April 2002.


* Geomagnetic storms have the potential to severely impair critical

* Consequences of geomagnetic storm activity can include widespread
power failures, pipeline corrosion, the shutdown of cable systems,
an increased drag on satellites, inaccurate navigational sensors
and the loss of millions of dollars in revenue.

* In Canada, it has been demonstrated that power systems, pipelines
and communications are at risk from the damaging effects of coronal
mass ejections (CME) and geomagnetically induced currents (GIC).

* Canadian infrastructure owners and operators have developed
effective operating procedures to deal with the threat of
geomagnetic storms. Advance warning systems provide infrastructure
owners and operators with the necessary information to prevent
the negative consequences of GICs through the implementation of
proactive conservative operating procedures.


The phenomenon of geomagnetic currents was first noticed in 1847.
In this year, the telegraph was the primary method of communication
and relied on batteries for power. Once, however, while an Aurora
Borealis was occurring, telegraph operators observed a disruption in
the transmission of communications. When the power was switched off,
the geomagnetically induced currents (GIC)[1] or "celestial power"
allowed transmissions to be conducted at a better quality than with
the use of batteries.

GICs are a result of erupting sunspots. Sunspots are massive dark
areas on the surface of the sun that lie on top of hurricanes of
electrified gas. When sunspots erupt, they release a coronal mass
ejection (CME)[2] at approximately 2 million miles per hour.
Geomagnetic storms occur when the CME impacts the Earth’s
magnetosphere, thereby disturbing the solar wind and reducing the
global magnetic field. While these powerful storms usually trigger
auroras, they can also damage energy and communication systems.

[1] According to Faraday’s law of induction, a temporal change of a
magnetic field is always accompanied by an electric field. Therefore,
an electric field is associated with geomagnetic activity. The
geomagnetic variation and the geoelectric field observed at the
earth’s surface depend primarily on ionospheric-magnetospheric
currents and secondarily on currents and charges induced in earth. A
part of the earth currents can flow into man-made conductors, like
power transmission systems, pipelines, telecommunication cables and
railroads. Such currents are called geomagnetically induced currents

[2] An observable change in coronal structure that occurs on a time
scale between a few minutes and several hours, and involves the
appearance of a new, discrete, bright white-light feature in the
coronograph field of view. They are associated with the large-scale,
closed magnetic structures in the corona. When a coronal mass
ejection occurs, a large quantity of material (10^15 – 10^16 g) is
sporadically ejected from the Sun into interplanetary space. The
speed of the leading edge of the coronal mass ejection may vary from
50 km/s to 1200 km/s. Average speed is about 400 km/s. The average
heliocentric width is about 45 degrees. Large geomagnetic storms are
caused by coronal mass ejections.

Full analysis is available at