(AP) -- Britain has added volcanoes and solar storms to floods, flu and terrorism on a list of threats to national security.
The highest-priority risks to Britain are pandemic influenza, coastal flooding, terrorist attacks and - a new addition - volcanic eruptions in countries like Iceland, according to the recently published 2012 edition of the government's National Risk Register for Civil Emergencies.
"Severe space weather" poses a threat to communications systems, electronic circuits and power grids, the list said. Solar storms - eruptions of magnetic energy and charged particles - are part of the sun's normal 11-year cycle, which is expected to reach a peak next year.
The storms can't hurt people, but can disturb electric grids, GPS systems and satellites. In 1989, a strong solar storm knocked out the power grid in Quebec, cutting electricity to 6 million people. Last week, the strongest solar storm since 2004 passed without major disruptions.
Last month, Parliament's defense committee called on the government to prepare for disruptions to electrical supplies and satellites from electromagnetic pulses - whether caused by the sun or by a nuclear weapon exploded in space.
Space war is not included on the British government's risk register.
"We are becoming more and more reliant on technology, and that technology is becoming more and more delicate," the committee's chairman, Conservative lawmaker James Arbuthnot, told Sunday's edition of The Observer newspaper. "Be afraid, very afraid."
Launched in 2008, the risk register assesses threats that are likely to endanger human welfare, the environment or security in Britain. It is the public version of the National Risk Assessment, which is classified.
Volcanic eruptions have been added to the list since the last edition in 2010. Ash from the April 2010 eruption of Iceland's Eyjafjallajokull volcano grounded European air travel for days.
But the British government says a more serious risk is posed by an effusive, of gas-rich, eruption. The 1783-84 Laki eruption in Iceland sent out noxious gases that spread as smog across Europe, causing crop failures, famine and thousands of deaths. The government said such an eruption "is now one of the highest-priority risks" Britain faces.
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More information: National Risk Register of Civil Emergencies: http://bit.ly/AqN0uz