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Weather and emergency management officials spent two days in Colorado this week. They were preparing for a storm far bigger than Katrina, one that could leave millions of people without electricity, running water or phone service, but it wouldn't cause hurricanes or tornadoes.
As NPR's Jon Hamilton reports, this type of storm begins on the surface of the sun.
JON HAMILTON: The sun has a lot of minor storms. Its molten surface often erupts, producing bursts of radiation that can light up the Earth's northern skies and interfere with radio signals. But every few decades or so, there's a vastly bigger explosion on the sun, one as powerful as a billion hydrogen bombs. Officials from the Europe and the U.S. wanted to know what might happen on Earth when the next one of these occurs.
Mr. TOM BOGDAN (Director, Space Weather Prediction Center) What we think could be close to a worst-case scenario.
HAMILTON: Tom Bogdan directs the Space Weather Prediction Center in Boulder. He was one of the U.S. officials who took part in a tabletop exercise there this week. It was based on massive solar storms that struck the Earth in 1859 and 1921, but of course back then we weren't dependent on satellites and other electronic devices that are vulnerable to these kinds of storms.
In the exercise, Bogdan says, the first sign of trouble came when radiation began disrupting radio signals and GPS devices. Ten or 20 minutes later, he says, electrically charged particles began to arrive.
Mr. BOGDAN: Those particles typically will impact satellites, and the high fluxes that were in the exercise basically took out most of the commercial satellites.
HAMILTON: The same satellites that carry stuff like telephone conversations and TV shows. Bogdan says those satellites also relay data that we depend on for a lot of daily tasks.
Mr. BOGDAN: When you go into a gas station and put your credit card in and get some gas, that's a satellite transaction.
HAMILTON: Disabled satellites were just the beginning. The worst damage came many hours later, when the solar storm began to induce electrical currents in high-voltage power lines. Bogdan says the currents were strong enough to destroy transformers around the globe.
Mr. BOGDAN: Starting in Sweden and then Canada and the Northeast U.S. into the Ohio Valley, and that more or less took out large parts of critical infrastructure.
HAMILTON: Without electricity, many people lost running water, heat, air conditioning and phone service, and places like hospitals had to rely on emergency generators with fuel for only two or three days. Craig Fugate, the administrator of the Federal Emergency Management Agency, also took part in the tabletop exercise. He says it showed that in many ways, solar storms are a lot like storms on Earth, but Fugate says a solar Katrina would present at least one unique challenge for agencies like his.
Mr. CRAIG FUGATE (Administrator, Federal Emergency Management Agency): Unlike a lot of natural hazards that are point specific, this would actually occur, depending on the rotation of the Earth on the sunlit side, and then ultimately as the geomagnetic storm took place and the impacts on satellites, perhaps worldwide.
HAMILTON: So a lot more people in a lot more places would need help. Fugate says that individuals, though, don't need to make any special preparation for a solar storm. He says the standard emergency kit of water and food and first aid supplies will work just fine.
Mr. FUGATE: So if you're taking those steps, and you go on to ready.gov, and you've got your family disaster plan together, you've taken the steps, whether it be a space storm, whether it be a system failure, whether it be another natural hazard that knocks the power out.
HAMILTON: Disaster officials say a solar Katrina isn't very likely to happen in any given year, but neither was the Katrina that hit New Orleans.
Jon Hamilton, NPR News.