The largest solar storm in five years is currently bombarding Earth. The brunt of the coronal mass ejection (CME) – a massive burst of charged particles hurtling from the sun at 4 million mph – struck our atmosphere at 11.00 GMT on Thursday 8th March. Space experts are warning of disruptions to satellites and power grids, but it’s still too soon to tell what the damage will be.

There’s a lot of uncertainty around the risk of geomagnetic storms, which can be prompted when magnetic energy stored in the sun’s atmosphere is suddenly released in a burst. The Forum’s 2012 report on Global Risks measured the perception of 469 experts, asking them to rate geomagnetic storms in terms of potential likelihood and impact over the next 10 years. Results showed very low concern over this risk relative to others. Out of the 10 environmental risks, geomagnetic storms were perceived as having the lowest impact. Out of all 50 global risks, geomagnetic storms also came in as one of the lowest concerns, perceived as the fourth lowest in terms of potential severity.

However, the OECD considers geomagnetic storms as one of five concerning possible future global shocks. The economic costs associated with geomagnetic storms are potentially very high, ranging from damage to space assets, which are hard to repair, damage to transnational infrastructure and the halting or redirection of air and water transport in the case of GPS failure. They do carry the potential to damage or disrupt our critical communication, navigation and electrical infrastructures – banging up our satellites and burning out components in electrical grids – but because storms which are powerful enough to do just that have occurred so rarely, it makes it hard to judge their impact.

According to reports, the CME impact today kicked off a geomagnetic storm classified as “minor”, meaning that weak power grid fluctuations can occur, minor impact on satellite operations are possible, migratory animals are affected at this and higher levels, and aurora will be commonly visible at high latitudes. So for now the hype about space weather seems to be overrated. However, it’s still too soon to say that the storm won’t pick up in intensity.

The real risk may be that of the boy who cried wolf – more research is needed to accurately assess the level of risk from geomagnetic storms, so that we aren’t sounding alarms for no reason. In the case of today’s storm, though, the biggest impact will probably be a beautiful light show for northern towns this evening.

For real-time updates on the CME, visit http://www.spaceweather.com, that is, unless it really does flare up.

Pictured: A NASA image of the solar flare (Reuters)

David Gleicher is a researcher with the Forum’s Risk Response Network.