NIO finds laughing gas on west coast
18 November 2000 22:58 IST The National Institute of Oceanography situated in Goa has found high contents of nitrous oxide - popularly known as laughing gas - in the Arabian Sea, expressing concern over ecological imbalance it is creating especially all along the western coast.
A team of scientists led by Dr S W A Naqvi, the first Indian whose research paper in this regard has appeared in the prestigious British science journal 'Nature', has found out highest accumulation of nitrous oxide and hydrogen sulphide after conducting research for the last three years off Goan coast.
"Primarily it appears to be the result of a natural process, but we also need to find out through more extensive research to what extent human activity has contributed to it", Dr Naqvi told this correspondent while explaining in detail about the findings of his landmark research.
Basically what he has found out is low oxygen and high nutrients in the sea water, the phenomena found all along from Gujarat to Kerala coast, covering around 1,80,000 sq kms of area. "It adds to global warming we witness nowadays", he states.
Dr Naqvi also does not rule out the possibility of the high content of nitrous oxide being the prime cause of global warming phenomena found along the coasts at over 50 sites in the USA, Japan and European countries, where industrial activity and chemical fertilisers was initially found to be the cause of it.
As a result of deep sea water getting more oxygen deficient and cooler due to occurrence of hydrogen sulphide, the fish like prawns and pomfrets runs away for life while what we fine nowadays in the market is plenty of sardines and mackerels which are found in upper level of the sea. This could thus affect the fishing industry extensively.
Probably this is the reason, says Dr Naqvi, the Mahim-Bandra causeway gets the foul smell due to the increased content of hydrogen sulphide. The study however demands further evaluation to know the rate of intensification, which is still unknown.
The study primarily reveals that the Arabian Sea water contains around 533 nanomoles of nitrous oxide (the laughing gas), which is around 5 nM in the normal water while the highest one recorded till date in the world was 173 nM in Peru in the early '80s.
"It is three times more than what was the world record till date", says Dr Naqvi. He feels the much higher rainfall recorded in the last few years along the western coast also needs to be evaluated taking into consideration the high concentration of the nitrous oxide in the sea water.
Though nitrous oxide is one of the green house gases along with carbon dioxide, methane etc, around 12 million tonnes of nitrous oxide is produced naturally in the sea water and on the earth and emitted in the stratosphere, which reacts with the ozone layer.
While the mother nature was taking care of this emission for thousands of years by perfectly maintaining the ecological balance, almost 4 MT of additional content of nitrous oxide is found in the atmosphere due to 'advanced' human activity like production of nylon, fertilisers etc, resulting into ecological imbalance.
According to Dr Naqvi, it is definitely a matter of concern as the green house concentration is building up world-wide, resulting into heating up of the earth and water temperature while the ice cover at both the poles is reducing since these green house gases contain properties to absorb the heat of the earth.
Meanwhile, a national daily, quoting Dr Raghunath Mashelkar, director general of the Council of Scientific and Industrial Research, has reported that the CSIR has decided to give a special grant of Rs five lakh to undertake more research on the same topic since they had been able to get their work published in such a `top notch' publication.
