Laughing gas largest threat to Ozone layer

NEW DELHI: Laughing gas or Nitrous Oxide (N2O) is the most abundant ozone depleting substance in the 21st century as the emissions of CFC (Chloro-Fluoro Carbon), another green house gas, has come down, a new study suggests.

"Although N2O is roughly 160th of CFC-11 in terms of ozone depleting potential, it has become the largest ozone depleting substance as Montreal Protocol has considerably reduced emission of others," said A R Ravishankara, Director Chemical Sciences Division, National Oceanic and Atmospheric Administration (NOAA), USA.

The research, which will be published in the latest issue of the Science magazine, studied N2O emissions through human activities especially by usage of fertilisers in agriculture.

"Our findings analyse the continuous emissions of N2O compared to that of CFC-11 from anthropogenic source, especially agriculture, he said. Speaking about the harmful effects of ozone depletion Ravishankara said, "The phenomenon of ozone depletion will increase the harmful UV radiation on earth, besides damage to infrastructure, plant life, among others."

Using an atmospheric model 'Garcia and Solomon 2 Dimensional model', scientists at Earth System Research Laboratory NOAA, have calculated the ozone depletion potential of Nitrous Oxide as compared to other harmful chemicals at steady state.