Thursday, 15 Jan, 2009 Environment

Besides warming our planet, exhaust fumes from cars were found to increase lightning strikes for many miles around.

Each working day the level of air pollution increases due to a lot of vehicles on the road. The pollution was noticed to change the rainfall patterns during the whole week by producing powerful updraft of air and more intense clouds. Recent findings suggest that pollution may cause lightning as well as rain.

Using ground-based National Lightning Detection Network, Daniel Rosenfeld and his team from the Hebrew University of Jerusalem calculated lightning strikes registered across the United States during the period between 1998 and 2008.

Researchers noticed that during the working week lightning strikes, recorded in south-eastern states, increased with pollution by about 25 percent. This region features a muggy air that creates low-lying clouds, the latter having enough space to rise and produce the charge necessary for a thunderstorm, informs New Scientist.

However, scientists were surprised to discover that the effect was not that strong in big cities with an increased level of pollution. Increased lightning strikes were registered in the suburbs and rural areas that surround these cities.

"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," outlines Rosenfeld. The researcher presented his study at the American Geophysical Union meeting in December 2008. According to Rosenfeld, the heat produced by urban areas is able to override the influence of pollution on lightning.