southern Asia threatens the lives of millions of people. Scientists say the pollution could increase lung disease and cause early death. The cloud is also damaging agriculture and affecting rainfall levels. It has affected many countries in southern Asia. The pollution cloud is three kilometers high. Scientists say it can move halfway around the world in a week.
The cloud is the result of forest fires, the burning of agricultural waste, and huge increases in the burning of fuels by vehicles, industries, and power stations.
Pollution from millions of bad cooking stoves has made the problem worse.
Many poor people burn fuels like wood and animal waste in such stoves.
Scientists say the cloud of pollution appears to cool the land and oceans by blocking sunlight.
They say it reduces the amount of sunlight reaching the Earth's surface by as much as 15 percent.
At the same time, heat inside the cloud warms the lower parts of the atmosphere.
Harmful chemicals from the cloud are mixing with rainfall.
This acid rain damages crops and trees and threatens public health. Scientists are concerned that the pollution will intensify during the