Sunshine: friend or foe?
Our sun warms the planet and gives us life, but it also threatens to blitz our IT, communications and power systems. Joshua Chambers investigates the danger of solar storms, and talks to the officials working to counter the risks
A cosmic belch 93 million miles out in space could cause chaos here on Earth. The lights could go out; our power networks fail; our communication grids go down; our navigation systems collapse; and our aeroplanes’ avionics falter, while their passengers would receive a substantial dose of radiation. In short, an explosive eruption of plasma from the sun could bring Britain to a standstill and cause long-term damage to its infrastructure.
Sometimes people think this scenario is science fiction, says Professor Mike Hapgood, head of the Space Environment Group at the Rutherford Appleton Laboratory – but the risks posed by extreme space weather events are real.
In recent years, government has woken up to the threat. In 2011, solar storms were added to the National Risk Register of Civil Emergencies, and for the past two years they’ve remained classified as a serious threat to the United Kingdom. After investigating the risks, the Civil Contingencies Secretariat in the Cabinet Office this year began developing the national structures and strategies required to counter the threat of extreme space weather events. This work involves a large number of departments, agencies, space scientists and industry groups; CSW has spoken with many of them to understand the progress that civil servants have made so far, and the lessons that can be drawn from their work.
It’s best to begin with a very brief science lesson.Dr Mike Willis, head of space weather at the UK Space Agency, explains that the main risk is from “coronal mass ejections [CMEs], which basically are eruptions from the surface of the sun that interact with the earth.”
How does something so far away interact with the earth? It all comes down to magnetism: just as the earth has magnetic north and south poles, generated by flows of hot liquid iron in the planet’s core, the sun also generates its own magnetic fields. Hot plasma and clouds of gas flow through it in loops, and due to the turbulent nature of the sun, they can become unstable and break down, exploding out from the star’s surface and taking with them the sun’s magnetic charge.
These clouds travel out from the sun at around 400km a second, Hapgood says, but sometimes reach 1,000km or even 2,000km a second. These are the “dangerous” ones, because they’ve got more energy and could have a big effect if they reach Earth. CMEs do occur regularly – and they’re particularly common this year, because the sun is at the peak of its 11-year cycle of activity – but most of them miss our planet completely. If they hit us, though, they can interact with our own magnetic field, causing electrical currents to flow around the planet and generating a magnetic storm.
The last true CME superstorm was the 1859 Carrington Event, named after the astronomer who guessed what was happening. But then, of course, electrical science and engineering was in its infancy, whereas today we’re utterly dependent on these technologies. Since the dawn of the space age, we’ve had only a couple of smaller CME strikes and some near misses – though even these have had a substantial impact. In 1989, a solar storm damaged a chunk of the Canadian energy grid, plunging the whole of Quebec into darkness for more than nine hours. A near miss happened last year, slamming into a couple of satellites but missing Earth itself. Large CMEs are fairly uncommon, then, but the scientific consensus is clear: the chances of the earth being hit by one the size of the Carrington Event “is inevitable: a matter not of if, but of when,” according to a comprehensive piece of research by the Royal Academy of Engineering.
It’s worth noting here that we could be hit by a substantial CME without experiencing any effects – and again, this comes back to magnetism. If the charge of the cloud matches that of Earth, with its own north and south poles lining up with those of our planet, then the cloud will be repelled away. However, if the charges are reversed, it’ll be pulled into Earth and cause havoc – unless proper mitigation strategies have been put in place.
It can take anything from 8-16 days for a cloud of plasma to arrive at Earth from the sun, but a really big one would get here in 24 hours, Hapgood says. We’d only know whether it has a south-north magnetic charge – and so would affect Earth – 20 minutes before it gets here. However, forecasting and better understanding of the sun means that these days we should have a pretty good indication a week or so in advance of any major CMEs set to erupt from the star’s surface.
The effects of any solar storm on Earth are variable and varied. Yet while a week’s notice isn’t a particularly long time – and 20 minutes is hopelessly short – many of the potential problems can be mitigated long in advance through good planning, extra capacity in systems, and coordination between scientists, government and industry.
Three main risks stand out: damage to aircraft; damage to satellites and communications infrastructure; and damage to the electricity grid. The last of these is the most severe – and potentially the most costly to the British economy.
The threat to aircraft is twofold: passengers can be exposed to harmful radiation; and electronic avionics systems can malfunction. The Royal Academy of Engineering (RAE) examined these risks in a paper this year on the impacts of extreme space weather on engineered systems and infrastructure.
A solar storm would increase pilot workload, it said, but modern aircraft have been designed to cope with the functional failure of components, equipment and systems. The health risks are greater, as passengers would be exposed to 20 times the radiation they’d be given in a planned exposure. Further, there could be panic amongst the passengers, their relatives and the press if people were exposed to this level of risk; the report notes that “an event of this type would generate considerable public concern.”
Aircraft would also be affected by the second major risk: damage to satellites and communications infrastructure. Any aircraft caught out by an electrical storm would not be able to communicate with an airport, because they rely on high frequency communications, which the RAE says would go down for several days. While there are “well-defined procedures” for aircraft in the air that lose communications, “there does not appear to be a defined mechanism for closing airspace or reopening [it] once communications have recovered,” it says.
Navigation systems would also be brought down by a solar storm. Satellites themselves can be badly damaged by the extreme radiation of a CME, and so might malfunction or meet the end of their lifespan far sooner than anticipated at a cost of many millions, Hapgood says. And if navigation satellites were taken down, aircraft and shipping would struggle. Further, global positioning systems are now used in a whole range of other areas, including providing accurate timing technologies for the majority of electronic systems, while broadcasting would struggle – leaving citizens unaware of what was happening and adding to the potential for mass panic.
The final risk is the biggest, given how widely it would affect the UK: the threat to the power networks. This was experienced in 1989 in Canada, and since then Britain’s National Grid has been working to mitigate the risks of it happening here. Andrew Richards, severe risk analyst for the National Grid, explains that the magnetic charge of a CME can cause power systems to overload. The transformers in a power grid, which are used to convert electricity from the high voltage in large power cables down to the level needed by kitchen kettles, can overheat and the oil that surrounds them start to boil. Some of them will switch off automatically when this occurs, but if they fail to do so and the overheating continues they will cost £3m each to replace.
A second problem could be that the magnetic charge interferes with the voltages running along power cables. Electricity levels could start to fluctuate, and when a voltage falls on one part of a grid, physics dictates that other voltages also plummet until the current drops to zero, causing a localised blackout on a whole section of the grid.
The threat has only been on government’s agenda since 2011, and its response has been split into three phases: understanding the threat and assessing the risks; finding weaknesses and gaps in our current capability; and building extra capability to mitigate those risks.
The first phase is reliant on monitoring for potential threats, and modelling to understand the nature of the problem. Monitoring is an international effort: the UK Space Agency coordinates its work with the European Space Agency (ESA), which has the technology to provide much of the monitoring. ESA has invested £38m in building new instruments and techniques to understand how to respond to space weather events, the UKSA’s Willis says. The Americans also have the National Oceanographic and Atmospheric Administration, which provides daily forecasts – and that’s what the National Grid uses.
Further, since government classified space weather as a risk, the UK’s Met Office has been given ownership of the national risk assessment, and is building its own forecasting service for British government and industry.
Modelling work is also vital, and this work is led by the Space Environment Impacts Expert Group (SEIEG), chaired by Hapgood. That board meets a couple of times a year, he says, and contains representatives from the Met Office, British Antarctic Survey, Defence Science and Technology Laboratory, Royal Academy of Engineering, and Civil Aviation Authority. Formed in 2010, it works with the Cabinet Office, Government Office for Science, and National Grid to provide expert advice on potential risks, and coordinate modelling work to build a better understanding of CMEs.
It also feeds into the Cabinet Office’s own project board, which was established in April this year. This board “provides guidance and assurance to the project, and is – in-turn – overseen by a programme board that looks at the two newest high priority National Risk Assessment hazards: effusive volcanoes and severe space weather,” explains Kirsty Rouillard of the Civil Contingencies Secretariat. The project board meets every 6-8 weeks to oversee and steer the project (see box for membership details).
Rouillard’s project board is a temporary structure, which is designed to build capability before handing responsibility over to other agencies and departments – who will be overseen by the Met Office. This transition is anticipated to take place in the middle of 2014. Decisions are yet to be taken on how exactly all the various new structures will look and interact, but in the event of a CME, the contingencies secretariat would coordinate all civil emergency responses, with officials working alongside a COBRA group of ministers.
Local government is also included in the response structures, Rouillard says. “The project recognises the importance of mitigation at the local level, and is working with the DCLG [Department for Communities and Local Government] Resilience and Emergencies Division and the devolved administrations to raise awareness of the risk and identify impact areas, [and] with local resilience forums and local responders to help them plan for the potential impacts.”
The major risks can potentially be mitigated, in advance of any CME event, through good planning, coordination and investment.
For example, National Grid has worked with the Department for Energy and Climate Change to build resilience into their systems. “You can never design a system to be absolutely 100% reliable,” explains Richards, but “National Grid operates to ridiculously high levels of reliability.” Through modelling, they’ve managed to understand the potential effects of a CME, and built redundancy into their system. “We don’t need to use every single bit of equipment that we have. If something breaks down, we can switch in a replacement.” They’ve modelled ways of spreading the extra voltage throughout the system so that individual transformers don’t get overloaded.
With early warning systems in place, power stations can be ready to divert more power to areas that are likely to be affected if the storm causes a voltage collapse. This power can be channelled along the spare cables that the National Grid has across the UK.
Once a CME has hit, the grid has been designed to monitor current power levels and provide feedback to National Grid staff. Monitoring devices aren’t placed at every transformer – “They are quite difficult to install so we don’t have that many of them,” Richards admits – but they are scattered across the network to provide an understanding of the broad picture.
To counter aviation risks, the Cabinet Office, Department for Transport, and Civil Aviation Authority have been working together to draw up mitigation strategies. With monitoring and modelling providing indications of the timing of a CME, and of the area likely to be affected, they can divert flights to avoid those areas. They’re also working to understand the longer-term health risks of being exposed to a CME while in flight, and working with industry to help minimize them.
On the satellite side of things, Professor Paul Cannon – author of the RAE report, and formerly for 25 years the head of space weather at the Ministry of Defence – says the key problem is that satellites would greatly age, and so satellite operators need to prepare for these risks and ensure they’re ready to replace their fleet more quickly than anticipated.
The second problem identified by Cannon is that of GPS: “We know [a CME] will have an impact on GPS systems, but it’s very hard to understand where GPS fits in our infrastructure. You know it’s in the car, but GPS timing is almost ubiquitous these days,” he says. Government is still trying to drill down into these risks. Meanwhile, the RAE recommends that ships and planes also have alternative navigation devices and methodologies as a backup.
How it’s shaping up
Cannon’s paper has formed the basis for much of government’s preparatory work. He believes that “we’re probably not sufficiently ready, but we’re getting there.” The National Grid has been preparing for this threat for years, he notes, but “others are in their infancy in dealing with it” – notably those using GPS systems.
That said, “I have been very, very impressed with the way that government has got stuck into this and has recognised it as a risk,” he stresses. “You know how reports quite often get swept under the carpet – this one certainly wasn’t.” The Cabinet Office has taken steps to include a wide range of organisations, and “while clearly government can’t open up to the advisory group and myself outside of government on everything, it has been very much a communal activity.”
The majority of recommendations made by the RAE have been taken up by the Cabinet Office, but one is still outstanding. Cannon’s report called for a UK Space Weather Board to provide overall leadership of all UK space weather activities. The Cabinet Office’s temporary project board isn’t quite the same thing, he notes. The Cabinet Office is still considering whether to establish a permanent board once its current work has finished, CSW understands.
A large CME event could, if it caught us unprepared, be catastrophic. However, the government has recognised the risks, and is coordinating preparatory work across industry, academia and departments. The work will take some time, but it’s a good case study of cross-departmental working.
Further, there could even be some opportunities for the UK from any CME event. As Willis notes, when CMEs hit the atmosphere, they produce luminous light shows called auroras. With better understanding of when and where a CME will hit, a new industry could develop: space weather tourism.
This article started by describing chaos, and it’s ending with government officials suggesting how, in fact, space weather events could help stimulate business growth. So there is opportunity here as well as risk: even in a bad mood, the sun is still our friend.