There are many ways this can happen, but the two most troubling ones have to do with electrical power blackouts and human radiation exposure.
The March 24, 1940 solar storm caused a temporary disruption of electrical service
in New England, New York, Pennsylvania, Minnesota, Quebec and Ontario. A storm on February 9-10, 1958 caused a power transformer failure at the British
Columbia Hydro and Power Authority. On August 2, 1972, the Bureau of
Reclamation power station in Watertown, South Dakota was subjected to large
swings in power line voltages up to 25,000 volts. Similar voltage swings were
reported by Wisconsin Power and Light, Madison Gas and Electric, and
Wisconsin Public Service Corporation. A 230,000-volt transformer at the
British Columbia Hydro and Power Authority exploded, and Manitoba Hydro in
Canada recorded power drops from 164 to 44 megawatts in a matter of a few
minutes, in the power it was supplying to Minnesota.
Perhaps the most dramatic, recent impact occurred in March 1989 during the
peak of the last sunspot cycle, when the sun produced one of the most
powerful storms ever recorded. On March 13, 1989 Alaskan and Scandinavian
observers were treated to a spectacular auroral display. In fact, this display
was seen as far south as the Mediterranean and Japan. Although many millions
of people marveled at this beautiful spectacle, many millions more were not so
happy about it. Hydro-Quebec on Saint James Bay did the best it could to
stabilize the power surges its lines received but ultimately failed the challenge.
For 9 hours, large portions of Quebec were plunged into darkness.
According to John Kappenman, who is in charge of Transmission Power
Engineering at Minnesota Power and Electric, the frequency of transformer
failures is higher in geographic regions where magnetic storms are also more
common such as the Northeastern US region which had 60% more
transformer failures. Moreover, the number of failures follow a solar activity
pattern of roughly 11 years. A conservative estimate of the damage done by
geomagnetic storms to transformers by Minnesota Power and Electric was
$100 million. Oak Ridge National Laboratories estimated that the collateral
impact to the economy of another March 1989 storm of only slightly greater
severity would produce a Northeast United States blackout, and cause $6
billion in damage. The North American Electric Reliability Council placed the
March 1989 and October 1991 storm events in a category equivalent to
Hurricane Hugo or the San Francisco earthquake in their impact upon the
national economy.
Although the atmosphere protects most airline flights well from space radiation, transcontinental flights taking the polar route pass through regions of Earth's magnetic field where particles become concentrated. Airline flight crews who travel these routes frequently can accumulate as many as .9 rem a year. This is more than the allowed annual dosages for nuclear plant operators and comparable to what shuttle astronauts receive during a typical one-week mission.
For more details about these effects, read the accompanying article
Solar Storms by Dr. Sten Odenwald (NASA/IMAGE)
