Brown cloud covering parts of India, China

BEIJING, Nov. 13 (UPI) -- A thick layer of soot and manmade particles stretches across parts of India and China, clouding the sky in some areas, a U.N. report said Thursday.

The combined effects of the atmospheric brown clouds and greenhouse gases is darkening cities such as Beijing and New Delhi and causing the Himalayas' glaciers to melt faster, the U.N. Environment Program said Thursday.

The brown clouds, which are the result of burning of fossil fuels and biomass, lead to the formation of particles like black carbon and soot that absorb sunlight and heat the air. The brown clouds may be masking the warming impacts of climate change by between 20 and up to 80 percent because the clouds contain particles that reflect sunlight and cool the surface, the report said.

Researchers said Bangkok, Beijing, Cairo, Karachi in Pakistan, Mumbai, New Delhi, Seoul, Shanghai, Shenzhen in China and Tehran are among the cities where soot levels are 10 percent of the total mass of all human-made particles.