The New Scientist offers new information about the relationship between car exhaust and lightning strikes, which is best illustrated during the work week when there is the most commuting.
In the south-eastern states, lightning strikes increased with pollution by as much as 25 per cent during the working week. The moist, muggy air in this region creates low-lying clouds with plenty of space to rise and generate the charge needed for an afternoon thunderstorm.
Surprisingly, the effect was not strongest within big cities with high pollution, but in the suburbs and rural areas surrounding them. “There is a misconception that if you get away from cities, you get away from the pollution. Actually, it follows you for hundreds of miles,” says Rosenfeld, who presented the research at the American Geophysical Union meeting in December.