Sun's magnetic field caused more lightning in Britain

Researchers in Britain have found that the country experienced around 50 percent more lightning strikes during the last five years as the Earth's magnetic field was bent by the Sun's own magnetic field.

The Sun plays a key role in the generation of lightning strikes on Earth by temporarily 'bending' the Earth's magnetic field and allowing a shower of energetic particles to enter the upper atmosphere.

"We have discovered that the Sun's powerful magnetic field is having a big influence on UK lightning rates," said Matt Owens from University of Reading and lead author.

"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," said Owens.

The Earth's magnetic field usually functions as an in-built force-field to shield against a bombardment of particles from space, known as galactic cosmic rays.

The Sun's spiral-shaped magnetic field called heliospheric magnetic field (HMF) is bent out as the Sun rotates.

This change can 'bend' the Earth's own magnetic field and this could expose some regions of the upper atmosphere to more galactic cosmic rays.

These rays are sent to different locations around the globe, which can trigger lightning in already charged-up thunderclouds, said Owens.

"This finding is an important step forward in our knowledge of how the weather on Earth is influenced by what goes on in space," said Giles Harrison, head of Reading's department of meteorology.

"We now plan to combine regular weather forecasts, which predict when and where thunderclouds will form, with solar magnetic field predictions. This means a reliable lightning forecast could now be a genuine possibility," said Owens.

The study appeared in the journal Environmental Research Letters.