GHG Emissions from International Shipping: Tentative Signs of Progress at Recent IMO Meetings

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Paris Agreement, Climate Change, International Maritime Organization


Until recently, efforts to reduce greenhouse gas (GHG) emissions from international shipping were periodically raised under the UN climate regime, while the International Maritime Organization (IMO) focused on air pollution and energy efficiency of new and existing ships. The result was an absence of meaningful action under the UN climate regime and principal IMO attention remained focused on air pollution from sulphur oxides (SOx), nitrogen oxides (NOx) and particulate matter (PM), with limited outcomes addressing GHGs. The Paris Climate Agreement, negotiated in 2015, and in force since November 2016, does not allocate responsibility for emissions from international shipping to any party, but does include emissions from this sector in its overall accounting of global emissions and in global emission reduction goals. Since Paris, it has become clear that the expectation of the global community is that the IMO will implement an effective strategy to reduce GHG emissions from this sector in line with the collective long-term goals of the Paris Agreement to keep global average temperatures well below 2 degrees above pre-industrial levels, while making efforts to keep them within 1.5 degrees, a goal that will require all reasonable efforts from all sectors, including international shipping, to decarbonize as quickly as is reasonably possible.

The initial IMO effort in addressing GHGs consisted of the first study on the subject presented at the Marine Environment Protection Committee (MEPC)’s 45th session in 2000. The MEPC is the Organization’s lead structure for the regulation of the environmental aspects of shipping. The study led to the adoption in 2003 of the Organization’s policies and practices related to the reduction of GHGs from ships, triggering an ongoing review of the issue and two further GHGs from shipping studies, the most recent in 2014. At its 57th session in 2008, the MEPC adopted nine fundamental principles as reference for future discussion, namely that the future framework: “(1) must be effective in contributing to the reduction of total global greenhouse gas emissions; (2) binding and equally applicable to all flag States in order to avoid evasion; (3) cost-effective; (4) able to limit, or at least, effectively minimize competitive distortion; (5) based on sustainable environmental development without penalizing global trade and growth; (6) based on a goal-based approach and not prescribe specific methods; (7) supportive of promoting and facilitating technical innovation and R&D in the entire shipping sector; (8) accommodating to leading technologies in the field of energy efficiency; and (9) practical, transparent, fraud free and easy to administer.” The ongoing debate has been marked by substantial concern over issues of equity, absence of reliable fuel use and emissions data, and divergent views on whether technical and operational measures are sufficient to substantially reduce emissions, or whether there is also need for a market-based mechanism(s)(MBM).