The IMO has addressed the issue of GHG from shipping for several years, resulting in the adoption of a “Revised GHG Strategy” at MEPC80 in 2023. Before the adoption of the revised strategy, years of negotiations and studies have paved the way for this adoption.
The IMO has conducted several comprehensive studies to understand and quantify GHG emissions from shipping, including:
- IMO GHG Study 2009: This study provided a baseline of GHG emissions from international shipping, estimating emissions for 2007 at approximately 1,046 million tonnes of CO2, representing about 3.3% of global emissions.
- Third IMO GHG Study 2014: This study updated previous estimates, revealing that shipping contributed around 2.2% of global CO2 emissions in 2012. It also highlighted the increasing trend in emissions and projected future scenarios.
- Fourth IMO GHG Study 2020: The latest study indicated that in 2018, international shipping accounted for approximately 2.89% of global CO2 emissions, with an increase in emissions compared to the previous study period. The report also explored various pathways to decarbonization, emphasizing the need for immediate and long-term actions.
Impact of GHG Emissions from Shipping on Climate
Shipping is a significant contributor to global GHG emissions, primarily CO2, methane (CH4), and nitrous oxide (N2O). These emissions contribute to global warming and climate change, causing rising sea levels, extreme weather events, and disruptions to marine ecosystems. The IMO recognizes that without intervention, emissions from the shipping sector could increase substantially by 2050, exacerbating climate change impacts. However, shipping was not included in the Paris Climate Agreement, wherefore a seperate agreement (strategy) nedded adoption at IMO level.
Initial GHG Strategy
Adopted in April 2018, the IMO’s Initial GHG Strategy aims to reduce GHG emissions from international shipping and phase them out as soon as possible. Key targets include:
- Reducing CO2 emissions per transport work by at least 40% by 2030 and pursuing efforts towards 70% by 2050 compared to 2008 levels.
- Reducing total annual GHG emissions by at least 50% by 2050 compared to 2008 levels, with the aim of phasing them out entirely.
Revised GHG Strategy
The IMO is working towards revising the Initial GHG Strategy, with the updated strategy expected to be adopted in 2023. The revised strategy will likely include more ambitious targets and a broader range of measures to achieve decarbonization. The focus will be on strengthening regulations, enhancing technological innovations, and promoting alternative fuels. The updated targets include:
- Interim Targets:
- Reducing carbon intensity by at least 40% by 2030 compared to 2008 levels.
- Achieving a reduction in total GHG emissions from international shipping of at least 30% by 2030 compared to 2008 levels.
- Final Targets:
- Pursuing efforts towards phasing out GHG emissions from international shipping entirely by 2050.
- Reducing total annual GHG emissions by at least 70% by 2050 compared to 2008 levels.
Short-, Medium-, and Long-Term Measures
The IMO categorizes measures to reduce GHG emissions into three timeframes:
- Short-term measures (2018-2023): These include enhancing energy efficiency standards, implementing operational measures, and promoting the use of cleaner fuels.
- Medium-term measures (2023-2030): These involve developing and deploying new technologies, improving operational efficiencies further, and establishing market-based measures (MBMs) such as carbon pricing.
- Long-term measures (beyond 2030): These focus on the widespread adoption of zero-emission fuels and technologies, achieving a fully decarbonized maritime sector.
Measures Already Adopted
Several key measures have been adopted by the IMO to reduce GHG emissions from shipping:
- Ship Energy Efficiency Management Plan (SEEMP): SEEMP requires ships to implement plans to improve energy efficiency through operational measures and best practices.
- Energy Efficiency Design Index (EEDI): EEDI sets mandatory energy efficiency standards for new ships, ensuring that new vessels are designed and built to be more energy-efficient.
- Energy Efficiency Existing Ship Index (EEXI): EEXI applies similar energy efficiency standards to existing ships, requiring modifications to meet efficiency targets.
- Carbon Intensity Indicator (CII): CII measures the operational carbon intensity of ships, providing annual ratings and promoting continuous improvement in energy efficiency.
Measures About to Be Adopted
The IMO is also working on additional measures to further reduce GHG emissions:
- Fuel Standard: The IMO is considering the adoption of fuel standards to regulate the carbon content of marine fuels, promoting the use of low-carbon and zero-carbon fuels.
- Pricing Mechanism: A market-based measure, such as a carbon pricing mechanism, is being explored to provide economic incentives for reducing GHG emissions. This could include carbon taxes or emissions trading schemes.
Other Regulatory IMO Measures Impacting GHG Emissions
In addition to the aforementioned measures, the IMO has implemented various regulations that indirectly impact GHG emissions:
- Fouling: Regulations on antifouling and biofouling are crucial as hull growth increases friction, leading to more fuel burned and higher GHG emissions. The IMO has adopted guidelines to manage biofouling to minimize this impact.
- Underwater Noise Reduction: The IMO is addressing underwater noise pollution, which can disturb marine life. Measures to reduce noise also often lead to improved propulsion efficiency and reduced fuel consumption, thereby lowering GHG emissions.
- MARPOL Annex VI: This annex regulates air pollution from ships, including NOx and SOx emissions, and promotes the use of energy-efficient technologies and cleaner fuels. Learnings from enforcement of these Annex VI emission regulation through UNCLOS (Part XII) will also apply to enforcement of IMO GHG measures.
Conclusion
The IMO’s efforts to reduce GHG emissions from shipping are crucial in mitigating the sector’s impact on climate change. Through various studies, strategies, and regulatory measures, the IMO is driving the maritime industry towards a more sustainable future. Continued innovation, international cooperation, and robust regulatory frameworks will be essential to achieving the ambitious targets set forth by the IMO and ensuring a significant reduction in GHG emissions from shipping.