The
1859 event didn't cause as much damage as it would today--electrical
engineering was in its infancy--but it was globally felt. Here's how a 2008 space-weather report from the National Academy of Sciences described that year's storm:
From
Aug. 28 through Sept. 4, auroral displays of extraordinary brilliance
were observed throughout North and South America, Europe, Asia, and
Australia, and were seen as far south as Hawaii, the Caribbean, and
Central America in the Northern Hemisphere and in the Southern
Hemisphere as far north as Santiago, Chile. Even after daybreak, when
the aurora was no longer visible, its presence continued to be felt
through the effect of the auroral currents. Magnetic observatories
recorded disturbances in Earth's field so extreme that magnetometer
traces were driven off scale, and telegraph networks around the
world--the "Victorian Internet"--experienced major disruptions and
outages.... In several locations, operators disconnected their systems
from the batteries and sent messages using only the current induced by
the aurora.
In other words, they literally ran the telegraphs from the electrical fields generated by the storm.
The
1859 event may be an extreme case, but there are more-recent examples
of such space weather: in March 1989 a geomagnetic storm took down
northeastern Canada's Hydro-Quebec power grid in just 90 seconds,
leaving millions without power in the cold for up to nine hours. And a
set of "Halloween" solar storms between October and November of 2003
sparked a National Academy of Sciences-led meeting on the societal and
economic impact of space weather, which served as the basis of the
report.
But it's not just scientists who are concerned about space
weather. Lloyd's of London, the giant insurer, issued a report on the
issue in 2010. In the foreword to the report, Lloyd's Tom Bolt warned
of a scientist-predicted spike between 2012 and 2015. "In terms of
cycles, we are in late autumn and heading into winter," he wrote then. A
severe space-weather event could prove devastating, according to the
Lloyd's report.
In the worst case it can permanently
damage transformers. In most cases, systems protecting power grids will
detect problems and switch off before serious damage occurs. However,
this may lead to a cascade effect in which more and more systems are
switched off, leading to complete grid shutdown. In these situations it
will take many hours to restore grid operation, causing disruption to
operations and services, and potential loss of income.
The
1989 storm permanently damaged a $12 million New Jersey transformer. In
1921, a storm 10 times as bad struck. Today, that storm would
permanently damage roughly 350 transformers, causing blackouts that
would affect as many as 130 million people, according to a Metatech
estimate.