The push and pull of the sun's magnetic field may encourage lightning strikes by bending the Earth's own magnetic field, allowing an influx of electric particles. Over a five-year period, researchers at the University of Reading recorded a 50 percent increase in lightning strikes when the Earth's magnetic shield was manipulated by the sun.

Earth is mostly shielded from cosmic radiation by its own magnetic shield. But galactic cosmic rays are thought to supercharge the Earth's own force field, instigating a chain reaction that results in the high-powered electric link between thundercloud and the ground.

Now, researchers suggest the positioning of the sun's magnetic field may influence the concentration, positioning and prolificacy of lightning storms. The sun's spiral-shaped magnetic field -- called the heliospheric magnetic field (HMF) -- acts like a bar magnet, sometimes pushing and sometimes pulling the Earth's own magnetic field. The nature of the sun's HMF and its effect on the Earth's field is dependent on the sun's rotational spin and the position of the Earth's orbit around the sun.

"We've discovered that the sun's powerful magnetic field is having a big influence on UK lightning rates," lead study author Matt Owens said in a press release. "The sun's magnetic field is like a bar magnet, so as the sun rotates its magnetic field alternately points toward and away from the Earth, pulling the Earth's own magnetic field one way and then another."

When analyzing data from the United Kingdom's Met Office, Reading researchers found that between 2001 and 2006, the U.K. witnessed 50 percent increase in thunderstorms when the sun's magnetic field was streaming toward the sun and away from Earth.

"From our results, we propose that galactic cosmic rays are channelled to different locations around the globe, which can trigger lightning in already charged-up thunderclouds," Owens said. "The changes to our magnetic field could also make thunderstorms more likely by acting like an extra battery in the atmospheric electric circuit, helping to further 'charge up' clouds."

If the researchers' new observations hold up under scrutiny and are legitimized by further analysis, it may signal a new chapter in meteorology as weather predictors begin factoring in the effects of solar radiation on dangerous lightning storms.

The work of Owens and his colleagues was published last week in the journal Environmental Research Letters.