Thick gray haze blankets the North China Plain and the mountain landscape to its south in this image captured by the MODIS on the Aqua satellite on October 23, 2009. The haze also flows across the Yellow Sea to the Korean Peninsula. Much of China’s haze comes from burning coal in industry, power plants, and households. Burning coal releases both particles and sulfates. Water condenses on the tiny sulfate particles, creating a chemical fog or smog under the right weather conditions.
The haze is a health concern because the tiny particles can reach deep into the lung where they can cause damage. Haze also impacts climate by deflecting sunlight from the Earth’s surface.