When emergency managers think of all-hazards disaster response, the most common scenarios include events like tornado outbreaks and chemical spills.
Preparedness for severe weather on the Sun does not typically fall at the top of the list, but NOAA’s National Weather Service is currently working to monitor a solar radiation storm which has the potential to disrupt power grids, GPS applications, airline communications, and even oil and gas pipelines.
The National Weather Service’s Space Weather Prediction Center is the nation’s official source of space weather alerts, watches and warnings for solar events which could impact the Earth. To put the importance of this work in perspective, a 2008 report of the National Research Council [leaves this blog] estimated that a powerful solar storm could cause $1 to $2 trillion in damage globally.
Science of Solar Storms
The Sun goes through cycles of high and low activity that repeats about every 11 years, with the next period of high activity expected in 2013. As we approach this period of high solar activity, the number of darker sunspots is increasing.
The magnetic field in sunspots stores energy that is released in solar flares — the most violent events in our solar system that can release a million times more energy than the largest earthquake.
How Does Severe Weather on the Sun Affect Us?
When solar flares occur on the side of the Sun facing Earth, geomagnetic field disturbances from these events may damage power systems and disrupt communications.
Although TV and commercial radio broadcasts are rarely affected, longer distance communication like navigation systems used by airplanes and ships can be “jammed” by increased levels of radio output from the Sun. Ships at sea require excellent navigation signals, and navigation errors caused by geomagnetic field disturbances can lead to wasted fuel, groundings, and spilled cargo.
During strong geomagnetic storms, electric power grids can experience fluctuating currents which can damage transformers and lead to widespread blackouts. In 1989, the entire province of Quebec, Canada, suffered an electrical power blackout after a severe geomagnetic storm, leaving millions of people without power for 12 hours.
A somewhat surprising result of solar storms is damage to oil and gas pipelines. At ground level, the result of geomagnetic storms is a changing magnetic field which induces currents that usually flow through the ground unnoticed. However, when good conductors, such as metal pipelines, are present, the currents travel through these as well. Eventually, these currents can cause enough corrosion in pipelines that they begin leaking and require spill response and environmental cleanup.
What Can We Do About It?
Using a large number of ground-based observatories and satellite sensors from around the world, NOAA receives solar data in real time which is then used to predict solar and geomagnetic activity and issue worldwide alerts of extreme events. When a space weather storm is predicted, satellite operators can temporarily halt communication with the spacecraft in orbit to prevent the jumbling of messages. If navigators are alerted that a geomagnetic storm is in progress, they can switch to a backup system. Airlines have even rerouted planes on polar routes where pilots depend on radio communications that are especially vulnerable to disruptions by space weather.
NOAA’s advance warning systems provide information needed to prepare and respond to severe weather systems, whether here on Earth, or on the Sun.
Get up-to-date space weather alerts, watches, and warnings from NOAA’s Space Weather Prediction Center [leaves this blog].