Rising Nitrous Oxide Emissions

Context:

According to a new study by the Global Carbon Project (GCP) titled “Global Nitrous Oxide Budget (1980-2020),” nitrous oxide emissions have been rising continuously between 1980 and 2020. The study found that in 2021 and 2022, nitrous oxide was released into the air faster than ever before, despite the need to cut greenhouse gases to combat global warming.

Relevance:

GS III: Environment and Ecology

Dimensions of the Article:

1. Key Findings of the Study
2. Implications of Rising Nitrous Oxide Emissions
3. Solutions to Reduce Nitrous Oxide Emissions
4. Conclusion

Key Findings of the Study

• Nitrous Oxide (N₂O) Emissions:
  • Human activities have led to a 40% increase in N₂O emissions (3 million metric tons annually) from 1980 to 2020.
  • The top five emitters of N₂O are China (16.7%), India (10.9%), the US (5.7%), Brazil (5.3%), and Russia (4.6%).
  • India ranks as the second largest emitter of N₂O globally, following China.
• Per-Capita Emissions:
  • India’s per capita emission of N₂O is the lowest at 0.8 kg/person, compared to China (1.3 kg/person), the US (1.7 kg/person), Brazil (2.5 kg/person), and Russia (3.3 kg/person).
• Atmospheric Concentration:
  • The concentration of atmospheric N₂O reached 336 parts per billion in 2022, a 25% increase over pre-industrial levels, surpassing IPCC estimates.
  • Currently, there are no technologies available to remove N₂O from the atmosphere.
• Sources of Nitrous Oxide Emissions:
  • Natural Sources:
    • Oceans, inland water bodies, and soil contribute 11.8% of global N₂O emissions (2010-2019).
  • Human-Driven Sources (Anthropogenic):
    • Agricultural activities account for 74% of human-driven N₂O emissions, mainly due to the use of chemical fertilizers and animal waste on croplands.
    • The growing use of nitrogen fertilizers in food production is increasing N₂O concentrations.
    • Other significant sources include industry, combustion, and waste treatment.
    • Increased demand for meat and dairy products has led to higher N₂O emissions through increased manure production.
• Emission Trends:
  • Agriculture: Emissions from agriculture continue to rise, while those from other sectors, such as fossil fuels and the chemical industry, are stable or declining.
  • Aquaculture: Emissions from aquaculture are growing rapidly, especially in China, though they are only a tenth of those from chemical fertilizers on land.
  • Regional Patterns: Of the 18 regions studied, only Europe, Russia, Australasia, Japan, and Korea showed decreasing N₂O emissions. Europe experienced the largest decrease (1980-2020), while China and South Asia saw the largest increases (92% from 1980 to 2020).

Implications of Rising Nitrous Oxide Emissions

• Global Warming Potential:
  • N₂O is about 300 times more effective than CO₂ at trapping heat over 100 years, significantly impacting global warming.
• Ozone Layer Damage:
  • N₂O breaks down in the stratosphere, releasing nitrogen oxides that damage the ozone layer, leading to increased UV radiation exposure.
  • This increased UV radiation can cause higher rates of skin cancer, cataracts, and harm to ecosystems reliant on UV protection.
• Agricultural Impact:
  • The use of nitrogen-based fertilizers in agriculture is a major contributor to N₂O emissions.
  • Growing food demand is likely to increase N₂O emissions further, creating a conflict between food security and climate goals.
• Climate Agreement Challenges:
  • Rising N₂O emissions pose a significant challenge to achieving the goals of the Paris Climate Agreement, which aims to keep global warming below 2°C compared to pre-industrial levels.

Solutions to Reduce Nitrous Oxide Emissions

• Optimized Fertilizer Use:
  • Utilizing soil sensors to optimize fertilizer application can reduce unnecessary nitrogen input, thereby minimizing N₂O formation.
  • Precision agriculture techniques can cut N₂O emissions by up to 50%, as noted in a Journal Nature study.
• Nitrification Inhibitors:
  • These additives slow down the conversion of ammonium in fertilizers to nitrate, which is a readily available form for N₂O-producing microbes.
• Cover Crops:
  • Planting cover crops during fallow periods helps retain soil moisture and nitrogen, reducing the risk of N₂O release.
• Anti-Methanogenic Feed:
  • Using feeds like ‘Harit Dhara’ (HD) or developing similar anti-nitrogen feeds for cattle will help reduce methane and nitrogen emissions.
• Cyclic Fuel Gas Generation:
  • Implementing a cyclic method to generate fuel gas from cattle dung, instead of allowing nitrogen emissions from anaerobic degradation, can minimize N₂O formation.
• Nano Fertilizers:
  • These fertilizers deliver nutrients directly and slowly to plant roots, minimizing excess nitrogen and reducing nitrous oxide emissions. They enhance nutrient absorption, potentially requiring less fertilizer overall.
• Emission Trading Schemes:
  • Implementing a cap-and-trade system for N₂O emissions can encourage industries and farmers to adopt cleaner practices. The European Union’s success with similar schemes for other greenhouse gases provides valuable insights.
• Financial Support for Farmers:
  • Governments can offer financial assistance to farmers transitioning to sustainable practices that minimize N₂O emissions. China’s significant reduction in N₂O emissions since the mid-2010s has been partly due to targeted subsidies for improved fertilizer management.
• Increased Research Funding:
  • Increasing funding for research on N₂O mitigation strategies, including improved fertilizers and waste management techniques, is essential for long-term progress.
• Stricter Regulations and Cleaner Technologies:
  • Implementing stricter regulations and promoting cleaner technologies can reduce N₂O emissions from industrial sources such as nylon production and nitric acid manufacturing.
• Combustion Process Optimization:
  • According to the IPCC Climate Change 2021 report, optimizing combustion processes in vehicles and power plants can help reduce N₂O emissions as a by-product.
• Waste-to-Energy Conversion:
  • The World Bank report highlights that advancements in waste-to-energy conversion and effective treatment of wastewater and agricultural waste can significantly lower N₂O emissions from these sources.

Conclusion

Mitigating nitrous oxide emissions effectively requires a comprehensive approach that combines technological innovations, regulatory frameworks, financial incentives, and international cooperation. By adopting these strategies, substantial progress can be made in reducing N₂O emissions and mitigating their impact on global warming and climate change.

-Source: The Hindu