x Abu Dhabi, UAEThursday 27 July 2017

Solar storm blows in but Earth is unmoved

For many, the most noticeable effect of the solar storm seems to have been a rather pleasant one with a magnificent display of the aurora borealis reported in northern latitudes.

LONDON // Earth appears to have emerged almost unscathed from a powerful solar storm that started battering the planet yesterday.

Although scientists warned the effects could linger until today, fears proved unfounded yesterday that satellites, GPS systems and even power networks could be affected by radiation bursts in space and geomagnetic storms.

Some interference with radio communication was reported, however, by aircraft flying over the Arctic.

But for many, the most noticeable effect seems to have been a rather pleasant one with a magnificent display of the aurora borealis reported in northern latitudes by the Finnish Meteorological Office.

The storm, the biggest in more than five years, was triggered by two huge solar flares that began on Tuesday and that sent charged particles hurtling towards Earth at 6.4 million kilometres an hour, the bulk of them due to arrive over a four-hour period starting at about 10am UAE yesterday.

But by yesterday afternoon, the US government's Space Weather Prediction Centre said there had been no noticeable effects on Earth beyond airliners' communication problems, with only a slight rise in low-energy particles detected by satellites.

Although there was no direct threat to human health, Paul Cally, a professor of solar physics at Monash University in Melbourne, said passengers on high-flying airliners might be subjected to a small increase in radiation, while "astronauts don't want to be out on spacewalks".

"There was a large explosion on the Sun and a large release of magnetic energy," he said.

"Along with that, there were these coronal mass ejections, like a big bubble of gas, that shot out into space and hit the Earth."

Increased radiation associated with these ejections put satellite systems, including GPS, at risk of disruption while the geomagnetic storms had the potential to interfere with communication systems and even cause surges in power grids, knocking out transformers.

The poles and northern latitudes were always going to be the areas most affected while those least at risk were tropical and subtropical regions around the earth's centre, including the Gulf.

Scientists at the US National Oceanic and Atmospheric Administration (Noaa) warned airlines to consider re-routing flights over polar regions because of the possible effects on communications and navigation systems.

A spokesman for British Airways in London said yesterday that the airline was monitoring the situation. When a smaller solar storm hit the planet in January, both United and Delta airlines diverted some flights to avoid communications problems.

Doug Biesiecker, a scientist at Noaa, told the BBC yesterday that the charged particles from the storm would create a geomagnetic storm in the Earth's protective magnetic field.

"This magnetic field keeps harmful radiation out. Now, the geomagnetic storm isn't going to take that magnetic field away from the Earth, but it's going to shake it," he said.

"And if you shake a magnetic field, you generate things like electric currents in the atmosphere and, say, in the power grid that criss-crosses pretty much every country on the planet now."

Mike Lockwood, a professor of solar-terrestrial science at Reading University in the UK, said that the impact of the storm depended on the direction of its magnetic field and whether it scored a direct hit on Earth or merely gave it a passing blow.

The 11-year cycle of sunspots - the intense magnetic activity that creates the storms - has been unusually quiet in recent years and has only recently emerged from a long solar "minimum" where there have been few if any sunspots, Mr Lockwood said.

"The indications are that we are now reaching a sunspot maximum, but it's still been very feeble. Up to now the sunspot cycle has been remarkably weak, so this may be the peak of this particular cycle," he said.

The worst effects of a solar storm in recent times were felt in Canada in 1989 when the power grid in Quebec was knocked out leaving six million people without electricity.

 

dsapsted@thenational.ae