The Herald Sun
Beijing: A thick brown cloud of soot, particles and chemicals stretching from the Persian Gulf to Asia threatens the world's health and food supplies, the UN said yesterday, describing it as the newest threat from global warming.
The regional haze, known as atmospheric brown clouds, contributes to the melting of Himalayan glaciers, reduces sunlight, and helps create extreme weather conditions that impact agricultural production, according to the report commissioned by the UN Environment Program.
These "brown clouds,'' caused by the burning of fossil fuels, wood and plants, play a significant role in exacerbating the effects of greenhouse gases in warming up the Earth's atmosphere, the report said.
"Imagine for a moment a 3km-thick band of soot, particles, a cocktail of chemicals that stretches from the Arabic Peninsula to Asia,'' said Achim Steiner, UN undersecretary general and executive director of the UN program.
"All of this points to an even greater and urgent need to look at emissions across the planet because this is where the stories are linked in terms of greenhouse emissions and particle emissions and the impact that they're having on our global climate.''
The phenomenon complicates the climate change scenario globally because the brown clouds also help cool the Earth's surface and "masks'' the impact of global warming by an average of 40 per cent, the study said.
Though it has been studied closely in Asia, the latest findings, conducted by an international collaboration of scientists, reveal that pollution hotspots are also seen in North America, Europe, South Africa and South America.