It was the terrifying prospect of lightning striking a historic windmill that troubled Andrew Farrell. A bolt five times hotter than the surface of the sun that instantly steamed the moisture in one of the mill’s wooden sections, causing it to explode. What if a raging fire engulfed the 160-year-old building? Perhaps most disturbing of all, he couldn’t shake the thought that this nightmare might be becoming more likely with each passing year—because of climate change.
Farrell of the Broads Authority, a British public authority, therefore decided to install a lightning protection system Sheep MillA 19th century windmill standing in a flat, broad expanse of wetland in eastern England known as the Norfolk Broads.
“These mills stand out as excellent conductors of the sky,” says Farrell. Inside Mutton’s Mill is a sporadic waterwheel, once used to drain marshes for farming. The mill itself is a protected Grade II listed building, 75 feet high including the sails. Thousands have been spent on its restoration in recent years.
Now, the mill’s four sails have hooked conductive rods on their ends, ready to catch a lightning strike and transmit it harmlessly to rods buried in a nearby bog. Farrell believes this could save the historic structure. But, he adds, “You know, if it gets hit, it’ll probably spook the owl that’s hanging out there.”
According to the Royal Meteorological Society in the UK, for every degree of atmospheric warming the air can hold about 7 percent more moisture. Warmer, wetter air means a greater risk of thunderstorms, and therefore lightning strikes, the society adds. Farrell says he has already noticed an anecdotal escalate in electrical storm activity in Norfolk. Scientists are still unsure how much lightning strikes might escalate globally. But organizations are already taking the threat seriously — and are quietly taking steps to protect buildings and critical infrastructure from future strikes.
According to information found in online documents, among the bodies currently considering the risk is Scottish Water, which has considered the possibility of an increased likelihood of lightning strikes at biogas production sites – such incidents could harm workers or members of the public. The International Civil Aviation Organisation, for its part, has considered the possibility of more repeated lightning strikes causing disruption to flight schedules, damage to aircraft or the immobilisation of radar towers. Network Rail in the UK also discusses the risk to signalling and electrical equipment on railways in a presentation document.
In a 2021 report, National Grid Electricity Transmission, the company that maintains the high-voltage network in England and Wales, said it had already gathered “evidence that lightning strikes around our assets are increasing in some areas”. While the system is currently largely resilient, the report added that “the impact of increased lightning strikes will need to be considered in the future”.
The U.S. Department of Defense is also concerned about lightning, says Caroline Baxter, a senior adviser at the Council on Strategic Risks. “Something that’s been underestimated is the risk that military installations face from the effects of climate change — including things like lightning,” she says, noting that some states that are particularly prone to lightning, such as Louisiana and Georgia, are also home to enormous military bases.