Brown Cloud: the rest sings our tune

India and the world have buried their differences over what was called the ‘Asian Brown Cloud’ and are now going to work on a joint scientific study that aims to get to the bottom of it. ‘‘It is important that we embark on a study that is based on scientific principles,’’ said Prodipto Ghosh, secretary, Ministry of Environment and Forests. After a three-day workshop on what has been re-named on India’s insistence as ‘Atmospheric Brown Cloud’, Paul Crutzen, Nobel Laureate and professor, Scripps Institution of Oceanography, admitted that it was a bit ‘‘alarmist’’ the way the first experiment had been reported and he ‘‘regretted it’’. In 2001, days before the Johannesburg Summit, United Nations Environment Programme (UNEP) came up with the finding that a dirty cloud of dust, soot and aerosol hung over the Indian Ocean and was a result of excessive fuelwood burning in the sub-continent. The Indian government reacted with anger mixed with denial as this line was used by developed nations to strengthen their argument that it was not just their Greenhouse Gases (GHG) that were responsible for climate change. Crutzen agreed that there was a ‘‘haze’’ over America and Europe but it was not as ‘‘black’’ as the one the Indoexp study found over India. The study was conducted by 200 scientists under the UNEP umbrella. But why Asia was India’s line. ‘‘There is also evidence that a similar phenomenon exists over Brazil and Africa, but we have started looking at it here first,’’ he said.

‘‘This is what we call ‘poor-man’s pollution’ — from burning biomass — and that is what is responsible for this brown cloud,’’ he said. At the workshop in Delhi, scientists were divided over whether the cloud was a result of biomass burning or from fuel. Come October, Indian scientists along with those of Sri Lanka, Nepal, Korea, Bangladesh, Thailand and China will embark on an instrument calibration exercise in the Maldives.

‘‘Only when we have checked, caliberated and compared the measurements of the radiometres will we know that they are working properly,’’ said Crutzen. The other anchor station would be set up in Korea.