GLOBAL NITROUS OXIDE BUDGET
Nitrous oxide (N₂O) is a potent greenhouse gas, significantly contributing to global warming and ozone layer depletion. A recent study by the Global Carbon Project (GCP) titled “Global Nitrous Oxide Budget (1980-2020)” highlights the alarming rise in N₂O emissions, particularly from human activities.
Key Findings of the Study
Alarming Rise in Emissions:
- N₂O emissions from human activities increased by 40% between 1980 and 2020, adding 3 million metric tons of N₂O annually.
Top Emitters:
- The top five emitters of N₂O are China (16.7%), India (10.9%), the United States (5.7%), Brazil (5.3%), and Russia (4.6%).
- India is the second-largest emitter globally after China.
Per-Capita Emissions:
- India has the lowest per-capita N₂O emissions (0.8 kg/person) compared to China (1.3 kg), the US (1.7 kg), Brazil (2.5 kg), and Russia (3.3 kg).
Concentration Increase:
- Atmospheric N₂O levels reached 336 parts per billion in 2022, a 25% rise over pre-industrial levels.
Lack of Removal Technologies:
- Currently, no technologies exist to remove N₂O from the atmosphere.
Sources of Emissions:
- Natural Sources: Oceans, inland water bodies, and soil contributed 11.8% of global N₂O emissions (2010-2019).
- Human-Driven Sources: Agriculture accounts for 74% of human-driven N₂O emissions, mainly due to chemical fertilizers and animal waste on croplands. Industry, combustion, and waste treatment are other significant sources.
Rate of Emissions:
- Agricultural emissions continue to grow, while emissions from fossil fuels and the chemical industry are stable or declining globally.
- Aquaculture emissions, though smaller, are rapidly increasing, especially in China.
Regional Emission Patterns:
- Europe, Russia, Australasia, Japan, and Korea have decreasing N₂O emissions. Europe saw the largest decrease due to reduced fossil fuel and industrial emissions.
- China and South Asia experienced the largest increases in N₂O emissions from 1980 to 2020, at 92%.
Implications of Rising Nitrous Oxide Emissions
Intensified Global Warming:
- N₂O is 300 times more effective than CO₂ at trapping heat over 100 years, significantly contributing to global warming.
Threat to Ozone Layer:
- In the stratosphere, N₂O decomposes, releasing nitrogen oxides that harm the ozone layer.
- Increased UV radiation due to ozone depletion can lead to higher rates of skin cancer, cataracts, and ecological harm.
Challenge to Food Security:
- The agricultural sector is a major N₂O emitter. Growing food demand will likely increase N₂O emissions, conflicting with climate goals.
Challenge to Paris Climate Agreement:
- Rising N₂O emissions pose a challenge to achieving the Paris Agreement goals of limiting global warming to below 2°C above pre-industrial levels.
Proposed Solutions to Mitigate Nitrous Oxide Emissions
Innovative Agricultural Practices:
- Precision Agriculture: Using technologies like soil sensors to optimize fertilizer application, reducing unnecessary nitrogen input and minimizing N₂O formation. Precision agriculture methods have the potential to reduce N₂O emissions by as much as 50%.
- Nitrification Inhibitors: Additives that slow the conversion of ammonium to nitrate, reducing N₂O production.
- Cover Cropping: Planting cover crops during fallow periods to retain soil moisture and nitrogen, reducing N₂O release.
- Anti-Methanogenic Feed: Using feeds like ‘Harit Dhara’ to reduce methane and nitrogen emissions from cattle. Developing similar anti-nitrogen feeds can minimize N₂O formation.
Using Nano-Fertilisers:
- Nano fertilizers deliver nutrients directly and slowly to plant roots, minimizing excess nitrogen and reducing N₂O emissions.
- They enhance nutrient absorption, potentially requiring less fertilizer overall.
Effective Policy Measures:
- Emission Trading Schemes: Implementing cap-and-trade systems for N₂O emissions to incentivize cleaner practices. The EU’s successful greenhouse gas emission trading schemes offer valuable lessons.
- Targeted Subsidies: Providing financial support for farmers transitioning to sustainable practices that minimize N₂O emissions. China’s reduction in N₂O emissions since the mid-2010s is partly due to targeted subsidies for improved fertilizer management.
- Research and Development: Investing more in research on N₂O mitigation strategies, such as enhanced fertilizers and advanced waste management techniques, is essential.
Addressing Emissions from Other Sources:
- Industrial Processes: Implementing stricter regulations and promoting cleaner technologies can minimize N₂O emissions from industrial sources like nylon production and nitric acid manufacturing.
- Combustion: Optimizing combustion processes in vehicles and power plants can help reduce N₂O emissions as a by-product.
- Waste Management: Advancements in waste-to-energy conversion and efficient treatment of wastewater and agricultural waste can greatly reduce N₂O emissions from these sources.
Conclusion
Addressing the rising nitrous oxide emissions is critical for mitigating global warming and protecting the ozone layer.
Implementing innovative agricultural practices, effective policy measures, and advancements in technology can significantly reduce N₂O emissions.
Global cooperation and dedicated efforts are essential to achieve the goals of the Paris Climate Agreement and ensure a sustainable future.