Why in News? 

Human emissions of nitrous oxide (N2O) a greenhouse gas 300 times more potent than carbon dioxide (CO2) increased by 30 per cent between 1980 and 2016 based on a study. Nitrous Oxide Emission and Impact to be taken as a serious concern.

About the Study

• Its global concentration levels increased from 270 parts per billion (ppb) in 1750 to 331 ppb in 2018 — a jump of 20 per cent.
• The growth has been the quickest in the past five decades because of human emissions.
• The research was conducted through an international collaboration between the International Nitrogen Initiative (INI) and the Global Carbon Project of Future Earth, a partner of the World Climate Research Programme.
  • It involved 57 scientists from 48 institutions in 14 countries.
• The study, which analysed 21 natural and human sources of N2O, found that 43 per cent of the total emissions came from human sources.
• Reason Behind the Increased Emission
  • It found that a major proportion of the N2O emissions in the last four decades came from the agricultural sector, mainly because of the use nitrogen-based fertilisers.
    • The growing demand for food and feed for animals will further increase global nitrous oxide emissions.
  • Most N2O emissions have come from emerging countries like India, China and Brazil.

What is Nitrous Oxide ?

• Nitrous oxide is a dangerous gas for the sustainable existence of humans on Earth.
• It has the third-highest concentration after CO2 and methane in our atmosphere among greenhouse gases responsible for global warming.
• N2O can live in the atmosphere for up to 125 years.

How nitrogen based fertiliser trigger increase emission of Nitrous Oxide ?

• Nitrous oxide emission from agricultural soil is due to the natural biochemical process in the nitrogen cycle.
• Application of nitrogen-based fertilisers stimulates microbes in the soil to convert nitrogen to nitrous oxide at a faster rate than normal.

Nitrous Oxide Emission and Impact

• N2O is also the only remaining threat to the ozone layer, for it accumulates in the atmosphere over a long period of time, just like CO2.
• The increase in its emissions means that the climatic burden on the atmosphere is increasing from non-carbon sources as well while the major focus of global climate change negotiations is currently centred on carbon its emissions and mitigation.

Efforts By India to Tackle Nitrous Oxide Emission

• India had led the first-ever nitrogen resolution adopted in the fourth UN Environment Assembly with the help of INI.
• India adopted the National Mission for Sustainable Agriculture as one of the eight missions listed under National Action Plan on Climate Change.
  • One of the objectives of the mission is to reduce agricultural greenhouse gas emission.

Way Forward

Based on the study reducing emission og Nitrous Oxide is a must to reduce the GHG emission. Reducing greenhouse gas emissions also has the co-benefits of reduced air and water pollution. It is possible to slow down N2O emissions if countries implement the 2019 United Nations resolution on sustainable nitrogen management.

Source : Down To Earth

GS III : Conservation, environmental pollution and degradation, environmental impact assessment

Current Affairs Compilation : 17 October 2020