A paper in the journal Science being published tomorrow says that man-made air pollution may cause droughts. The researchers studied hilly areas in China, finding that air pollution from lower elevations can reduce water resources by 30 to 50 percent on mountain tops.
This study replicated the results of a similar one that was published in 2003 by Colorado and Nevada researchers based on work done near Steamboat Springs. Those researchers found that on days of heavy air pollution, snow deposition in the mountains can decline by as much as 50 percent.As with all things weather-related, the mechanisms that cause this are complicated. But essentially air pollution results in smaller particles in the air around which cloud droplets can form. Smaller particles mean less water content in the clouds, along with as much as half the amount of snow from a storm.
So air pollution may help cause droughts or, at a minimum, less water storage at high elevations.