Posted: May 13, 2014 6:35 PM by Pat Shingleton
Researchers originally believed that pollution increased convection inside thunderheads, encouraging deeper, longer lasting clouds. Original observations depicted taller, larger anvil-shaped clouds but recent studies have altered that belief. According to researchers at the Department of Energy's Pacific Northwest National Laboratory pollution decreases the size of cloud particles and increases the lifespan of ice crystals. These ingredients cause anvil clouds to last longer as opposed to clear air development. Polluted air has more aerosols which attract water droplets. The study showed that small water droplets and ice crystals, in polluted air, are too light to fall, linger longer and lead to longer lasting clouds.