Britain has added volcanoes and solar storms to floods, flu and terrorism on a list of threats to national security. The 2012 edition of the government\'s National Risk Register for Civil Emergencies says the highest-priority risks to Britain are pandemic influenza, coastal flooding, terrorist attacks and volcanic eruptions in countries like Iceland. And it adds \"severe space weather\" as a newly assessed risk that could disrupt communications systems, electronic circuits and power grids. 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. Last week, the strongest solar storm since 2004 passed without major disruptions.