London, August 11
A 3 km brown cloud hanging over South Asia could have thrown the monsoon rains off course, says a major study by the United Nations Environmental Programme (UNEP).
“The global models used in the report suggest the haze may reduce precipitation over northwest India, Pakistan, Afghanistan, western China and neighbouring western central Asian region by between 20 and 40 per cent,” the report says.
“There have been two consecutive droughts in 1999 and 2000 in Pakistan and the northwestern parts of India while increased flooding in the high rainfall areas of Bangladesh, Nepal and the northeastern states of India.”
The massive brown cloud is becoming devastating for India, says the UNEP study, conducted between 1995 and 1999 in an experiment involving 200 scientists from India, Europe and the USA.
Air pollution caused by the cloud is leading to at least half a million deaths a year. Agricultural production has begun to decline as a result of the cloud.
This haze, which pilots have been talking about for a long time, is clearly visible over much of South Asia and is not just dust and gases, the UNEP report shows.
It is manmade particles “made up of sulphates, sulphuric acid, black carbon, fly ash, nitrates and the like,” Prof V. Ramamurthy of the University of California, who was associated with the project, told reporters here on Friday.
The haze was “reducing the amount of direct sunlight reaching the earth surface in these areas by 10 to 15 per cent,” Prof Ramamurthy said.
This has had radical consequences. It is reducing evaporation and cloud formation and rainfall. The reduced sunlight is also reducing photosynthesis and therefore agricultural productivity.
The report says the Asian Brown Cloud, as it has come to be called, is “modifying rainfall patterns including those of the mighty monsoon” and also “triggering droughts in western parts of the Asian continent”.
The report says research in India indicates the haze may reduce the winter harvests by as much as 10 per cent.
“The haze is the result of forest fires, burning of agricultural wastes, dramatic increases in burning of fossil fuels in vehicles, industries and power stations and emissions from millions of inefficient cookers burning wood, cow dung and other bio fuels,” says UNEP’s executive director Klaus
Toepfer. IANS
