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A new level of extreme weather is upon us: solar super storms

By news editor, on 10 June 2013

pencil-iconWritten by Emily Burns, a UCL PhD student working in the Structural Biology laboratory at the London Research Institute.

The surface of the Sun is a searing 5,500 degrees Celsius, with an ionised atmosphere that is brimming with magnetic fields. As activity levels rise, this giant ball of gas hurls its matter towards Earth, altering our own magnetic field and atmosphere.

Solar flares on the surface of the Sun.

Solar flares on the surface of the Sun.
Image courtesy of NASA Goddard Photo & Video.

The threat of extreme space weather wreaking havoc on our world all sounded a tad science fiction to me, until Dr Lucie Green explained all at the Cheltenham Science Festival.

As the audience was shown videos of the Sun releasing huge amounts of energy and expelling its atmosphere towards us, it became apparent that solar super storms – discussed a great deal in the media recently in light of a report released by the Royal Academy of Engineering – are a very real threat.

Scientists have monitored the activity of the Sun and can now give us an idea of how a solar storm is formed.

Initially, groups of sunspots appear on the surface, where activity levels are higher than the rest of the star. Bursts of light known as solar flares are then released from within these spots, taking just eight minutes to reach us. These flares change the ionising radiation in the Earth’s atmosphere and are the first component of solar activity driving a super storm.

Secondly, energetic particles are accelerated out as energy is released from the Sun. They reach us in approximately thirty minutes and can continue to shower Earth for days if further energetic eruptions occur.

The final component of solar activity – and by far the most impressive – is a coronal mass ejection (CME) of solar plasma. This bubble of solar activity erupts on the surface of the Sun and launches the charged atmosphere out into space.

It travels at a mere few hundred kilometres per second (practically snail pace compared to the initial flares) and reaches Earth in 15–72 hours. The charged gas of the CMEs hitting our atmosphere interferes with the Earth’s magnetic field and results in geomagnetic storms.

The level of impact these CMEs have on Earth depends on the speed that they travel at, how close they come to Earth and the orientation of the magnetic fields both within the CME and in the solar wind ahead of it.

Scientists are trying to understand the physics behind this solar activity so that they can predict when a solar super storm will occur, and how dramatic it will be. A spacecraft is currently being built (with a planned launch in 2017) to go into orbit closer to the Sun than ever before.

This spacecraft will hopefully allow scientists to understand better all three components of solar activity, how they reach the Earth and what their impact is upon arrival.

But what will happen to Earth if one of these super storms actually occurs? Luckily, Professor Paul Cannon was on hand to fill us in.

While small solar storms occur all of the time, the last super storm was in 1859 – and there’s a 50% chance that there will be another one in the next 50 years. The problem is that we haven’t experienced anything of this magnitude since we launched our satellites and started observing the world outside our own – which makes guessing the consequences of another rather difficult.

While scientists don’t know exactly how it’ll play out, they do know that some of our supergrid transformers will be damaged; which, in turn, effects everything from our lights to our sewage system.

We will lose 10% of the approximately 100 satellites we have in space for a few days; and all satellites will be aged by the storm. Air passengers at the time of the storm will be subject to the equivalent of three chest CT scans’ worth of radiation, with all other aircraft grounded due to loss of GPS.

That doesn’t just mean you can’t use your car’s satellite navigation for a few days – this will affect everything from the emergency services to financial trading. The internet in developed countries should withstand the hit and pacemakers are very unlikely to be affected. The real problem right now is how to protect those in the space stations. There is an area within the station that has more protection, but it won’t be enough in a large event and will probably result in a life-threatening dose of radiation.

Why are we hearing about this now? It turns out that the Sun is at the peak of its activity cycle and it will be for the next two years.

But while this means there will be more flares and CME, there just isn’t enough data on super storms to allow scientists to estimate whether that makes the likelihood of one occurring higher or not.

The good news seems to be that both scientists and the UK government are taking this very seriously. With continual advances in space research, our understanding of these colossal events – and when the next one may occur – can only get better.

As the riveting talk drew to a close, we were all told to be prepared. On that note, I’ll definitely be packing a map on my next road trip.

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