The electro-magnetic pulse threat (EMP) is the danger of serious disruption to the national infrastructure caused by a sudden burst of electromagnetic radiation. Two potential causes were examined: a high altitude nuclear explosion and increased solar activity (space weather). In both cases the effect could be similar: disruption to power supplies, and damage to satellites and computer chips.
Until recently the greater threat was considered to be a nuclear explosion, and the EMT remit consequently fell to the Ministry of Defence (MoD). This threat is considered to be growing again, particularly “if nuclear non-proliferation efforts are not successful.” Iran is specifically mentioned. However, the committee is not satisfied with MoD preparations or attitude, commenting that “an appearance is given that the MoD is unwilling to take these threats seriously.” The MoD’s nuclear attitude is traditionally one of deterrence and reaction, but the report considers that this is “somewhat complacent”, and that “wargaming and planning is required to assess the likely involvement of MoD resources in dealing with the consequences of EMP events.”
Since 2008, the report notes, the potential effect of space weather has been included in the EMP threat to civil authorities. Space weather is defined as changes in the near earth space environment caused by solar activity. The report notes the approximately 11-year cycle in solar activity, and that the next ‘solar maximum’ is due in 2013. The National Security Strategy published in 2010 concluded that “The likelihood of a severe space weather event is assessed to be moderate to high over the next five years, with the potential to cause damage to electrically conducting systems such as power grids, pipelines and signalling circuits.”
It is difficult to quantify the potential effect of a major EMT incident, although the Carrington Event of September 1859 is used as a possible ‘worst case’ scenario. This is named after British astronomer Richard Carrington who observed a solar flare strong enough to be seen with the naked eye. “The huge coronal mass ejection (CME) that followed induced enormous electric currents that surged through telegraph systems, causing shocks to telegraph operators and setting fire to papers. Operators were able to disconnect their batteries and continue to send messages using only this induced current. The impact was so wide-ranging that auroras, normally limited to polar regions, were observed as far South as Hawaii and the Caribbean.”
It is generally considered that a nuclear EMT event would be more severe, if somewhat more localised, than a space weather event. The report notes that the “adoption of optical cables for most telephone and internet communications makes them largely immune to space weather effects.” The wireless internet and satellite communications are less resilient. However, the report is particularly concerned about potential damage to the national power grid. “A failure of the national grid for example, would inevitably have repercussions for a wide range of businesses and services, from energy supplies, water processing, traffic control and logistical systems and even parts of the finance sector.”
The report concludes that “a severe event could potentially have serious impacts upon UK infrastructure and society more widely. It is essential that this hazard is sufficiently recognised and addressed by the Government and relevant civil bodies.”