Space weather: a new hazard
Space weather: a new hazard
Increasingly, we are becoming more and more dependent on power and communication systems in many different aspects of our daily lives. This leaves us even more susceptible to disruption during particularly violent periods of solar weather.
Bad solar storms could potentially shutdown electricity power grids around the UK if the position of electrical power transformers is not moved in order to cope with powerful geomagnetic induced currents (GIC) caused by coronal mass ejections (CME) from the Sun.
Last month, several solar scientists discussed the potential hazards that we are faced with when the Sun ejects these massive bursts of solar wind. Speaking at the British Science Festival in Aberdeen, Professor Lucie Green from University College London, explained that coronal mass ejections are the result of the destabilisation of the ‘S’ shaped structures that can form in sun spots on the Sun’s surface due to a build-up of electrically-charged gas. The S shaped ‘magnetic flux rope’ tussles with opposing arch-like structures on the sun’s surface in an effective tug-of-war until one of the opposing forces gives way resulting in an eruption of geomagnetic gas.
Dr James Wild from Lancaster University went on to explain how the expelled magnetic gas, or solar wind, interacts with our planet’s magnetic field, and if the polarity of the two are parallel, the Earth’s radiation belts effectively ‘peel back’ and merge with the magnetic rays in the solar wind. This releases the plasma particles normally held within the Earth’s radiation belts into the planet’s atmosphere resulting in increased GIC activity.
Dr Alan Thomson from the British Geological Survey, told the Festival-goers that these currents can then move through the Earth’s atmosphere, and even the crust, mantle and core of the planet, causing our power and electricity supplies to be affected.
Modern electricity transformers have built-in safety devices designed to shut down the generator if there is a dangerous rise in GIC. Thomson used the example of the failure of the Hydro-Quebec grid in March 1989 to illustrate the impact the shutdown of the power grid had on the communities it supplied. The 90 second emergency shutdown of the generator left five million residents without power. It took engineers nine hours to restore power to the blacked-out communities and cost the operating company $12 million in direct costs. The cost to the economy was estimated to be around $2.5 billion.
Severe solar storms not only have the ability to shut down power grids, but can also cause damage to communication satellites above the Earth’s atmosphere. Bad space weather can cause the radiation belts around the Earth to swell in size, engulfing unprotected communication satellites sitting just outside the usual breadth of the belts. Modern life relies heavily on communication satellites in many different industries. Loss or damage of satellites could affect important systems like the stock market, GPS systems, as well as domestic and industrial power supplies.
Thomson pointed out that a lot of aging electrical transformers are ill-equipped to cope with the level of energy in geomagnetic currents and as a result, older generators may become unstable if affected during a geomagnetic storm. The creation of newer power stations complete with GIC safety mechanisms, in more closely-located clusters, can help to absorb and diffuse the impact of dangerous currents. He said that as the energy industry moves towards becoming more sustainable, the potential effects of GIC will have to inform the layout and capacity of future power stations to withstand regular geomagnetic activity in the Earth’s atmosphere.
The potential of bad space weather to interfere with our economy, power and communications, raises the questions of why we aren’t made more aware of the possibility of such events. The destruction caused by Hurricane Katrina in 2005 and the Japanese tsunami in 2011 should be seen as a wake-up call to global leaders of the devastating impact natural disasters can have on a country and its inhabitants, argued the panel. Dr Thomson reasoned the increased frequency of these so-called ‘black swan’ events had had an unlikely positive effect in raising the importance of research into the Earth’s weather and the impact of factors like climate change and increased solar storm activity. However, to be better equipped for future changes, he said that investment in this work needed to continue.
All the speakers made it clear that the message for policy makers is that research and development in the field of space weather needs to continue so that scientists can better predict when CMEs are likely to happen and the effect they could potentially have on the Earth’s power and communication systems. Governments around the world also need to consider the impact future solar storms will have on the infrastructure of our modern world.