Should we be worried about geomagnetic storms caused by solar activity? Some experts say that we should and claim that huge explosions stemming from the magnetic field and plasma from the sun's corona - called coronal mass ejections (CMEs) - could produce powerful geomagnetic storms with the potential to cause severe damage to Earth.
When CMEs come into contact with Earth's atmosphere, they disturb its magnetic field temporarily through geomagnetic storms that affect power grids and can lead to citywide blackouts and inhibited radio communications. They even have the ability to disrupt satellites in orbit. But are these interruptions dangerous enough that we should worry?
"The short answer to this is absolutely," said Doug Biesecker of the National Oceanic and Atmospheric Administration's (NOAA) Space Weather Prediction Center. "The possibility of an extreme CME causing a very powerful geomagnetic storm is real. There's considerable uncertainty to how frequent such storms are at the level where we worry about huge impacts on the power grid and the resulting impacts that a lack of electricity would have. Is it a one in 50, one in 100 or one in 1,000 year event? We just don't know."
The strongest geomagnetic storm ever recorded in Earth's history took place in 1859. Dubbed the "Carrington Event" or "1859 Superstorm," it damaged telegraph systems across Europe and North America and stimulated the formation of auroras across the world.
Scientists believe that if such an event were to hit the Earth now, it would devastate us even more due to our increased reliance on technology such as mobile devices, Internet and satellite navigation systems.
In response to the increased danger of such threats, the U.S. government released the National Space Weather Strategy and the National Space Weather Action Plan in October 2015. The plans outline various ways to improve our understanding of space weather hazards, including monitoring, prediction and mitigation techniques.
"There was a new National Space Weather Strategy published by the White House in October, 2015," Biesecker said. "This and an accompanying Action Plan specify what federal agencies and industry must do in the coming years to be prepared for not only forecasting an extreme event, but ensuring the nation is resilient to the impacts of such an extreme event."
Despite these dangers, we are now past the maximum of the current solar cycle, which took place in April of last year. Does this mean that we're in the clear?
"While solar activity such as solar flares and CMEs roughly correlate with the solar cycle, as we consider more extreme events, this correlation gets weaker," Biesecker concluded. "So, while we are headed toward fewer flares and CMEs on average, the likelihood of extreme events is always present. Even in the last solar cycle, the most extreme events in that cycle occurred two to four years after the maximum of the solar cycle."
