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Historic Background


IMO and the UNFCCC policy framework

It fell to scientists to draw international attention to the threats posed by global warming.  Evidence in the 1960s and '70s that concentrations of carbon dioxide (CO2) in the atmosphere were increasing first led climatologists and others to press for action.  It took years before the international community responded.

In 1988, an Intergovernmental Panel on Climate Change (IPCC) was created by the World Meteorological Organization and the United Nations Environment Programme (UNEP), which issued a first assessment report in 1990 which reflected the views of 400 scientists.  The report stated that global warming was real and urged that something be done about it.

The Panel's findings spurred governments to create the United Nations Framework Convention on Climate Change (UNFCCC), which was ready for signature at the 1992 United Nations Conference on Environment and Development - more popularly known as the "Earth Summit" - in Rio de Janeiro.

The Kyoto Protocol adopted in Kyoto, Japan, in 1997 is an international agreement linked to the UNFCCC, which major feature is binding targets for 37 industrialized countries and the European community for reducing greenhouse gas (GHG) emissions.  The detailed rules for the implementation of the Protocol were adopted at COP 7 in Marrakesh in 2001, and are called the "Marrakesh Accords".  The Kyoto Protocol entered into force on 16 February 2005.

The Kyoto Protocol contains provisions for reducing GHG emissions from international aviation and shipping and treats these sectors in a different way to other sources due to their global activities that is, pursuing though the International Civil Aviation Organization (ICAO) and the International Maritime Organization (IMO) respectively.  Emissions from domestic aviation and shipping are included in national targets for Annex I countries.  ICAO and IMO regularly report progress on their work to UNFCCC.

No reference to IMO (nor ICAO) is made in either the articles of the 2015 Paris Agreement on Climate Change (the Paris Agreement) or the decisions to implement the agreement, including on the pre-2020 ambition.

MEPC 69 (April 2016) welcomed the Paris Agreement and acknowledged the major achievement of the international community in concluding the agreement, recognized and commended the current efforts and those already implemented by IMO to enhance the energy efficiency of ships, widely recognized and agreed that further appropriate improvements related to shipping emissions can and should be pursued, and recognized the role of IMO in mitigating the impact of GHG emissions from international shipping.

As requested by Assembly resolution A.963(23), the IMO Secretariat continuously reports to UNFCCC SBSTA under the agenda item on "Emissions from fuel used for international aviation and maritime transport" and participates in related United Nations system activities.

IMO begins work on GHG emissions

In September 1997, an International Conference of Parties to the MARPOL Convention, which adopted the Protocol of 1997 to amend the MARPOL Convention (MARPOL Annex VI), also adopted resolution 8 on CO2 emissions from ships.  This resolution invited the Marine Environment Protection Committee (MEPC) to consider what CO2 reduction strategies might be feasible in light of the relationship between CO2 and other atmospheric and marine pollutants.  The resolution also invited IMO, in cooperation with the UNFCCC, to undertake a study of CO2 emissions from ships for the purpose of establishing the amount and relative percentage of CO2 emissions from ships as part of the global inventory of CO2 emissions.

In December 2003, the IMO Assembly adopted resolution A.963(23) on IMO Policies and practices related to the reduction of greenhouse gas emissions from ships, which urged MEPC to identify and develop the mechanism(s) needed to achieve the limitation or reduction of GHG emissions from international shipping.  In the ensuing years, MEPC has since been energetically pursuing measures to limit and reduce GHG emissions from international shipping.

IMO GHG studies

In 2000, the First IMO GHG Study on GHG emissions from ships was published, which estimated that ships engaged in international trade in 1996 contributed about 1.8 per cent of the world total anthropogenic CO2 emissions.

The Second IMO GHG Study, published in 2009, estimated international shipping emissions in 2007 to be 880 million tonnes, or about 2.7% of the global total anthropogenic CO2 emissions.

The Third IMO GHG Study, published in 2014, estimated international shipping emissions in 2012 to be 796 million tonnes, or about 2.2% of the global total anthropogenic CO2 emissions. The Study also updated the CO2 estimates for 2007 to 885 million tonnes, or 2.8%.

Energy efficiency of international shipping

In July 2011, IMO adopted mandatory measures to improve the energy efficiency of international shipping through resolution MEPC.203(62), representing the first-ever mandatory global energy efficiency standard for an international industry sector, the first legally binding instrument to be adopted since the Kyoto Protocol that addresses GHG emissions and the first global mandatory GHG-reduction regime for an international industry sector.

The amendments adopted by resolution MEPC.203(62) added a new chapter 4 entitled "Regulations on energy efficiency for ships" to MARPOL Annex VI. This package of technical and operational requirements which apply to ships of 400 GT and above, are known as the Energy Efficiency Design Index (EEDI), applicable to new ships, which sets a minimum energy efficiency level for the work undertaken (e.g. CO2 emissions per tonne-mile) for different ship types and sizes, and the Ship Energy Efficiency Management Plan (SEEMP), applicable to all ships. These mandatory requirements entered into force on 1 January 2013.

The EEDI has been developed for the largest and most energy-intensive segments of the world merchant fleet and, following the inclusion of additional ship types, will embrace approximately 85% of emissions from international shipping. EEDI reduction factors are set until 2025 to the extent that ships constructed in 2025 will be required to be at least 30% more energy efficient than those constructed in 2014. The SEEMP establishes a mechanism for operators to improve the energy efficiency of existing ships against business-as-usual operations, in a cost-effective manner and also provides an approach for monitoring ship and fleet efficiency performance over time.

A study undertaken following the adoption of the mandatory energy efficiency measures indicates that the uptake of SEEMP measures will have a significant effect in the short to medium term, while EEDI measures should have a greater impact in the longer term, as fleet renewal takes place and new technologies are adopted. Estimates suggest that a successful implementation of this energy efficiency framework by 2050 could reduce shipping CO2 emissions by up to 1.3 gigatonnes per year against the business-as-usual scenario.

MEPC 70 (October 2016) agreed on the need for a thorough review of EEDI Phase 3 (1 January 2025 and onwards) requirements, including discussion on its earlier implementation and the possibility of establishing a Phase 4. Phase 3 requirements provide that new ships be built to be 30% more energy efficient compared to the baseline. MEPC 71 established a Correspondence Group on EEDI review beyond phase 2, under the coordination of Japan, and instructed it to submit a progress report to MEPC 72, an interim report to MEPC 73 and a final report to MEPC 74 in 2019.

Adoption of a mandatory fuel oil consumption data collection system

At MEPC 65 (May 2013) several delegations recognized the importance of enhancing energy efficiency and reducing fuel consumption with subsequent reductions of CO2 emissions and other pollutants emitted to air. The Committee noted considerable support for the development of further measures to enhance the energy efficiency of shipping and to use a three-step approach, i.e. data collection and data analysis, followed by decision-making on what further measures, if any, are required (the three-step approach).

MEPC 70 (October 2016) adopted mandatory MARPOL Annex VI requirements for ships to record and report their fuel oil consumption. Under the amendments, starting from 2019, ships of 5,000 GT and above (representing approximately 85% of the total CO2 emissions from international shipping) will be required to collect consumption data for each type of fuel oil they use, as well as, additionally, other specified data, including proxies for "transport work". The aggregated data will be reported to the flag State after the end of each calendar year and the flag State, having determined that the data have been reported in accordance with the requirements, will issue a Statement of Compliance to the ship. Flag States will be required to subsequently transfer this data to an IMO Ship Fuel Oil Consumption Database. The Secretariat is required to produce an annual report to the MEPC, summarizing the data collected.

Development of a comprehensive IMO Strategy on reduction of GHG emissions from ships

MEPC 70 also approved a Roadmap for developing a comprehensive IMO strategy on reduction of GHG emissions from ships, which foresees an initial GHG reduction strategy to be adopted in 2018. The Roadmap contains a list of activities, including further IMO GHG studies and significant intersessional work with relevant timelines and provides for alignment of those new activities with the ongoing work on the aforementioned three-step approach to ship energy efficiency improvements. This provides a way forward to the adoption of a revised strategy in 2023 to include short-, mid-, and long-term further measures, as required, with implementation schedules.

MEPC 70 also agreed to hold a series of intersessional meetings of the working group on reduction of GHG emissions from ships.  The first intersessional meeting was held back-to-back with MEPC 71 in June 2017. The second intersessional meeting held in October 2017 made progress in starting to shape the draft initial IMO GHG Strategy. The third intersessional meeting will be held the week before MEPC 72 in April 2018 where the working group is instructed to finalize a draft text of the initial IMO GHG Strategy that MEPC 72 is expected to adopt.