S.K. Satheesh, associate professor at the Centre for Atmospheric and Oceanic Sciences, Indian Institute of Science, Bangalore, was honoured last week by the Third World Academy of Sciences with its 2011 prize in Earth Sciences that carries a prize of 15,000 dollars.
For over 19 years, Dr. Satheesh has been studying atmospheric aerosols, the tiny suspended particles comprising natural elements like sea salt, desert sand, and volcanic ash and the soot released by human activities like burning biomass and fossil fuels.
The announcement from Trieste, Italy, said Dr. Satheesh was chosen for the award for his contribution to the understanding of atmospheric aerosols and their impact on the radiation balance of the earth-atmosphere system and climate.
He shared the prize with Wu Fuyuan of the Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing. Talking to The Hindu on a visit to his parents' house at Perungadavila, a suburb of Thiruvananthapuram, Dr. Satheesh said he was proud to be the first Malayali scientist to bag the award.
Aerosols, Dr. Satheesh explains, are one of the two major causes for global warming, the other being carbon dioxide. “While developed countries are responsible for most of the carbon dioxide emissions, developing nations account for a major share of the black carbon aerosol caused by industrial and automobile emissions and biomass burning,” he says.
On completing his MSc. in Physics from the University of Kerala in 1992, Dr. Satheesh joined Vikram Sarabhai Space Centre as a research fellow in the Atmospheric Sciences division. “Aerosol study was an emerging field at that time. It was a risky subject for a Ph.D. since there was not much of studies on the subject. But I saw it as a challenge,” he recalls.
He went on to do post-doctoral research in atmospheric radiation at the University of California before returning to India to join the Indian Institute of Science.
The study of aerosols has exposed Dr. Satheesh to some of the most demanding environments, from the frozen expanses of the Antarctic region to the tropical seas and the rarefied heights of the atmosphere above the Earth. He has sailed to the southern ocean in the Antarctic on board a research vessel, flown dozens of sorties on a specially-equipped aircraft and has spent two years on a small island in the Arabian Sea.
Black carbon aerosol, Dr. Satheesh says, can influence cloud formation and alter rainfall pattern. It may also enhance atmospheric warming by green house gases. “Observations over India for the last two decades show a five-fold increase in aerosol abundance,” he points out.
Dr. Satheesh feels that there is much to learn about the way aerosols affect regional and global climate and their influence on the Indian monsoon.
According to him, the fast increase in aerosol abundance and its distribution in high altitudes close to the Himalayan region is disturbing because of its potential to cause faster melting of glaciers.
Dr. Satheesh is the lead author of chapter seven on ‘Aerosols and Clouds' in the fifth assessment report of the Inter governmental Panel on Climate Change (IPCC) slated to be released in 2013. “It is an honour for an Indian scientist to be selected for this role,” he says.
He feels that India and China, the two countries that contribute about 60 per cent of black carbon, need tight restrictions, including industrial licensing, to bring down aerosol emissions. “The National Carbonaceous Aerosol Programme, a joint venture between the Indian Space Research Organisation and the Union Ministry of Environment and Forests, involving observations at 100 stations across the country, will provide India with valuable inputs for climate modelling,” he says.
He says the next stage of research on the topic would be the impact of aerosols on ozone depletion.