AIR pollution may help to form clouds but it inhibits rain, according to
Daniel Rosenfeld of the Hebrew University of Jerusalem. Data from weather
satellites show that streaks of cloud form downwind of polluted urban and
industrial areas, he says. Yet few of these clouds produce any rain.
The reason for this paradox is that pollution provides plenty of particles
which water condenses on to form the droplets that make up clouds. So clouds
form in the polluted air. But the large number of particles disperses the water
finely, causing many small droplets to form.
The result is that none…
