From the Issue Brief: "Geomagnetic storms -- a type of space weather that creates disturbances that affect the planet's magnetic field --have the potential to cause significant damage across the globe with a single event. Severe geomagnetic storms can disrupt the operation of electric power transmission systems and critical infrastructures relying on space-based assets. A geomagnetic storm that degrades the electric power grid would affect not only the energy sector but the transportation, communications, banking, and finance sectors, as well as government services and emergency response capabilities. Despite the potentially serious consequences of a severe geomagnetic storm, a literature review indicates that the state of the art for assessing the security risk from geomagnetic storms is still in development. There are examples of analyses that describe threat, vulnerability, and consequence, but they are not integrated, primarily because of the weakness in the threat analysis. Without a sense of the likelihood of such events or at least a mechanism for relative comparisons, cost-benefit analyses have been unable to demonstrate the utility of investing either in hardening or in testing and maintaining operational procedures. The Federal government lacks comprehensive national-level geomagnetic storm risk management assessments and strategies, and no standing entity exists to coordinate cross-Federal government geomagnetic storm risk analysis. This Issue Brief suggests that the Federal government should consider whether it is appropriate to conduct a formal, comprehensive risk assessment regarding severe geomagnetic storms."
United States Dept. of Homeland Security: http://www.dhs.gov/