Why doesn't this article use the term "Asian brown cloud"?

Brown clouds making Delhi, Mumbai darker: UN

Beijing: Vast "brown clouds" of pollution are making Asian cities, including New Delhi and Beijing, darker, melting Himalayan glaciers and intensifying regional monsoons, a UN report said on Thursday.

India as a whole had become darker by about two percent per decade between 1960 and 2000, while China had lost its natural light by about three percent to four percent per decade from the 1950s to the 1990s.

The natural light was between 10 percent and 25 percent dimmer in cities such as Karachi, Beijing, Shanghai and New Delhi, the report said.

A team of scientists highlighted the three effects after studying a "more than three-km thick layer of soot and other man-made particles that stretches from the Arabian Peninsula to China and the western Pacific Ocean", the United Nations Environment Programme (UNEP)said.

Even low levels of air pollution may pose stroke risk

The "atmospheric brown clouds" result from the burning of fossil fuels and biomass, and in some areas also worsen the impact of climate change caused by greenhouse gas emissions, the UNEP report said.

At least 13 major cities in Asia and other regions, including Beijing and New Delhi, get less sunlight because of the pollution, while its effects on air quality and agriculture in Asia pose "increasing risks to human health and food production for three billion people."

The other darker cities identified were Bangkok, Cairo, Dhaka, Karachi, Kolkata, Lagos, Mumbai, Seoul, Shanghai, Shenzhen and Teheran.

Asian brown cloud: Information from Answers.com

Viewed from satellite photos, the Asian Brown Cloud appears as a giant brown stain hanging in the air over much of Asia and the Indian Ocean.

Brown clouds making Asian cities 'dimmer': UN report- ET Cetera-News By Industry-News-The Economic Times

Globally, however, brown clouds may be countering or "masking" the effects of climate change by between 20 and up to 80 per cent, said the report.