Fighting Climate Change in the Civil Aviation and the Shipping Sector

Table of Contents
Civil Aviation Sector
Civil aviation is one of the fastest-growing sources of greenhouse gas (GHGs) emissions worldwide. With increasing international passenger and cargo flights, the sector faces mounting pressure to align with global climate goals. To address this, the International Civil Aviation Organization (ICAO) introduced the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA)—a landmark initiative aimed at reducing aviation’s carbon footprint.
What is CORSIA?
- Adopted in 2016 during the 39th ICAO General Assembly attended by 191 countries.
- First global deal to limit greenhouse gas emissions from international aviation.
- Applicable to civilian passenger and cargo flights (excluding humanitarian, medical, and firefighting operations).
How Does CORSIA Work? From 2021 onwards, any increase in airline COâ‚‚ emissions beyond 2020 levels must be offset through climate-friendly activities such as tree planting and carbon absorption projects.
How Does CORSIA Work?
From 2021 onwards, any increase in airline COâ‚‚ emissions beyond 2020 levels must be offset through climate-friendly activities such as tree planting and carbon absorption projects.
Phases of Implementation
| Phase | Timeline | Nature |
| Pilot Phase | 2021-2023 | Voluntary |
| First Phase | 2024-2025 | Voluntary |
| Second Phase | 2027-2035 | Mandatory for all member states |
- Voluntary till 2026, but most major nations are expected to participate.
- Review every 3 years to ensure transparency.
- Prevents double counting of offsets (e.g., forest protection projects cannot be reused to negate aviation emissions elsewhere).
Why Did Developing Countries Oppose CORSIA? Countries like India, China, and Brazil raised concerns:
- Equity Issues: Developed nations historically contributed more to emissions, yet developing countries face equal obligations.
- Economic Burden: Aviation growth is crucial for emerging economies; mandatory offsets may increase operational costs.
- Technology Gap: Limited access to sustainable fuels and advanced aircraft technology compared to developed nations.
ICAO’s Broader Climate Goals: CORSIA is part of ICAO’s strategy to halve aviation carbon emissions by 2050 compared to 2005 levels. Other measures include:
- Sustainable Alternative Fuels (SAF): Biofuels and synthetic fuels to replace conventional jet fuel.
- Efficient Aircraft Operations: Improved designs, lightweight materials, and fuel-efficient engines.
- Infrastructure Improvements: Modernized air-traffic management systems to reduce fuel wastage.
Shipping Sector
The shipping industry plays a crucial role in global trade, but it also contributes significantly to climate change. Between 2016–2023, the sector was responsible for 2.3% of global anthropogenic CO₂ emissions. Unlike aviation, shipping is not covered under the UNFCCC framework, making international regulation essential.
To address this, the International Maritime Organization (IMO) has introduced strategies and mechanisms to reduce greenhouse gas emissions from ships, including the 2023 IMO Greenhouse Gas Strategy and proposals for a global carbon tax on shipping.
The 2023 IMO Greenhouse Gas Strategy
The IMO adopted a comprehensive framework in 2023 to reduce emissions from international shipping.
Key Targets
- 40% reduction in carbon intensity (COâ‚‚ emissions per transport work) by 2030.
- Adoption of zero or near-zero GHG technologies and fuels to represent at least 5% (striving for 10%) of total energy use by 2030.
- Focus on large ocean-going ships, which dominate industry emissions.
Measures
- Deployment of alternative fuels (biofuels, hydrogen, ammonia).
- Energy-efficient ship designs and improved operations.
- Modernized port and logistics infrastructure to reduce fuel wastage.
First Global Carbon Tax on Shipping – Delayed (October 2025)
In April 2025, IMO’s sub-committee approved a framework for new fuel standards and a global carbon pricing mechanism. Countries were scheduled to vote in October 2025 to enforce measures from 2027.
Aim Encourage ships to adopt low-emission fuels or pay a carbon fee starting 2028.
Expected Impact
- Estimated revenue: $40 billion by 2030.
- Funds ring-fenced for maritime decarbonization projects (not for broader climate finance).
Criticism
- Limited impact: Expected to reduce emissions by only 10% by 2030, short of IMO’s 20% target.
- Equity concerns: Does not address climate finance needs of developing countries.
Opposition Oil-rich nations (Saudi Arabia, UAE, Russia, Venezuela) resisted the deal.
Delay in Implementation In October 2025, countries voted to delay carbon-free shipping measures. Political opposition, including statements from U.S. leadership, influenced the decision.
Conclusion
Both civil aviation and shipping are critical sectors in the fight against climate change. ICAO’s CORSIA and IMO’s Greenhouse Gas Strategy represent landmark global efforts to regulate emissions beyond the UNFCCC framework. While aviation focuses on offsetting and sustainable fuels, shipping emphasizes carbon intensity reduction and taxation mechanisms. However, challenges remain – equity concerns, political opposition, and limited impact of current measures.
FAQs
1.What is CORSIA in aviation?
CORSIA stands for Carbon Offsetting and Reduction Scheme for International Aviation, introduced by ICAO in 2016. It is the first global framework to limit greenhouse gas emissions from international civil aviation.
2.How does CORSIA connect to ICAO’s climate goals?
CORSIA is part of ICAO’s broader plan to halve aviation emissions by 2050 compared to 2005 levels. Alongside offsetting, ICAO promotes sustainable fuels, efficient aircraft operations, and modernized air-traffic management.
3.Is CORSIA relevant for UPSC preparation?
Yes. CORSIA is highly relevant for GS Paper 3 (Environment & Sustainable Development), Essay Paper (Climate Change, Global Governance), and International Relations. It’s a prime example of global cooperation in tackling climate change.
4.What is the global carbon tax on shipping?
A pricing mechanism where ships must either adopt cleaner fuels or pay a fee for emissions starting 2028.
5.Why is the shipping sector important in climate change discussions?
Because it contributes 2.3% of global COâ‚‚ emissions and is not covered under UNFCCC, requiring separate regulation.


