In the wake of a recent EMP scare, both scientists and politicians alike have taken another look at the possible catastrophe that an Electromagnetic Pulse would be. Electromagnetic pulses, also known as EMPs, are massive surges of energy that can come from a severe solar flare or from a high altitude nuclear explosion. A large EMP is would induce high currents and voltages in electrical systems across power lines, which could cause major blackouts over a large area for a long period of time.  An article at science.nasa.gov describes how ground currents induced during geomagnetic storms can actually melt the copper windings of transformers at the heart of many power distribution systems. Sprawling power lines act like antennas, picking up the currents and spreading the problem over a wide area.  While military and intelligence networks may be shielded against EMP, the rest of the country’s technological infrastructure is not.

According to Michael Del Rosso, the former chairman of the Institute of Electrical and Electronics Engineers’ in an article at Newsmax.com, To make matters worse, as Critical Infrastructure Protection Committee, added - even if no hostile power responds catastrophically to our vulnerability to EMP, a similar level of devastation can be caused by natural phenomena. Specifically, intense solar flaring of the kind currently occurring could, according to an estimate by Lloyds of London, leave up to 40 million Americans without power for as long as two years. On September 1-2, 1859, the largest recorded geomagnetic storm in history, called the Carrington Event, occurred. Basically this was a gigantic solar flare followed by an extreme geomagnetic storm where people saw Aurora as far south as the Caribbean. Geomagnetic activity triggered by the solar event electrified telegraph lines shocked technicians and set their telegraph papers on fire.

Modern electronics are much more susceptible to the threat of EMP, especially because of how interconnected the modern electric grid is..
"A contemporary repetition of the Carrington Event would cause … extensive social and economic disruptions," the report warns. Power outages would be accompanied by radio blackouts and satellite malfunctions; telecommunications, GPS navigation, banking and finance, and transportation would all be affected. Some problems would correct themselves with the fading of the storm: radio and GPS transmissions could come back online fairly quickly. Other problems would be lasting: a burnt-out multi-ton transformer, for instance, can take weeks or months to repair. The total economic impact in the first year alone could reach $2 trillion, some 20 times greater than the costs of a Hurricane Katrina or, to use a timelier example, a few TARPs.

An article in the Washington Times says that,

“A number of rogue states and strategic competitors are actively investing in the development of precisely this sort of capability. Thus, Russia, which during the Cold War carried out extensive experiments relating to EMP, has actively contemplated its use on a number of occasions since the Soviet collapse. China, too, is investing in EMP weapons as part of its “assassin’s mace” - an asymmetric military arsenal through which Beijing seeks to challenge U.S. primacy in the Asia-Pacific region. North Korea, for its part, is believed to have tested a “super-EMP” weapon powerful enough to create massive disruption in the continental United States back in 2009. Iran, which carried out EMP-related ballistic-missile tests in the Caspian Sea in the late 1990s, has since publicly explored the possibility of using such a capability against America.”

Although a nuclear EMP attack is much less likely than terrorists using biological or chemical weapons, the repercussions are so massive that the USA and other countries may need to take a look at hardening infrastructure. Fortunately, protecting electronics and critical infrastructure against an EMP is doable. It involves enclosing every electronic component with a metallic cage that blocks out electromagnetic waves.  Fortunately, many computers and data centers are already shielded – many need to in order to work properly and some shielding is required by the FCC.  Much of this shielding might not be enough though, so more robust shielding materials, especially for the cords, cables, and/or wires that connect devices to external entities such as power supplies or networks will be needed.

To address this threat, Congressman Trent Franks and former House Speaker Newt Gingrich introduced a bill Tuesday to protect the grid. Called the SHIELD Act, or the Secure High-voltage Infrastructure for Electricity from Lethal Damage, the bill would push the federal government to install grid-saving devices, surge protectors that could save the transformers and power system from EMPs.

  
http://www.newsmax.com/FrankGaffney/EMP-Vulnerability-Rumsfeld-grid/2013/08/05/id/518700#ixzz2bIn1e6yD

http://www.dailymail.co.uk/sciencetech/article-2382527/A-near-miss-Earth-Devastating-electromagnetic-pulses-knocked-power-cars-phones-occured-weeks-ago.html#ixzz2bINQgENo

http://www.washingtontimes.com/news/2011/dec/15/electromagnetic-pulse-a-real-threat/#ixzz2bJV2eRex

http://www.csmonitor.com/2005/1219/p25s02-stct.html

http://www.foxnews.com/science/2013/06/18/shield-act-to-protect-from-solar-catastrophes-electromagnetic-pulses/#ixzz2bJp6pmK

http://science.nasa.gov/science-news/science-at-nasa/2009/21jan_severespaceweather/