Much of the debate within IMO is about the extent to which the decarbonisation of shipping can stagnate and how quickly it is possible. Last week, a report by the International Transport Forum and the Organisation for Economic Co-operation and Development (OECD) indicated that international shipping could be almost entirely decarbonised by 2035, with maximum deployment of known technologies. This is the same target year that the Marshall Islands pushed towards IMO. Traut M, Larkin A, Anderson K, McGlade C, Sharmina M, Smith T. CO2 reduction targets for international navigation. Clim Pol. 2018;18(8):1066–75. While IMO adopted two technical energy efficiency measures in 2011 and requires ships to report on their fuel consumption from 2019, no overall caps or reductions in ship emissions have been set. Discussions on a market-based mechanism also failed in 2013.
“Every year we allow emissions from shipping to increase, it destroys the carbon budget. After that, more radical action will have to be taken,” Comer said. The report indicates that a combination of different measures would be the most cost-effective way to reduce marine emissions, including renewables and alternative fuels such as advanced biofuels, methanol, ammonia and hydrogen. While IMO has adopted certain energy efficiency standards for shipping, emissions are not expected to decrease without additional effort due to the expected strong growth in the international maritime sector. However, discussions have always been stalled. There are several problems to overcome. There is concern that the effects of an agreement may be disproportionate to flag states with many registered vessels. Only six flag states – Panama, China, Liberia, Marshall Islands, Singapore and Malta – account for more than half of the ship`s global CO2 emissions. Gilbert P, Bows A. Explore the possibilities of a complementary subglobal policy to reduce CO2 from shipping. energy policy.
2012;50:613–22. The other end of the spectrum is mainly dominated by emerging countries, such as Brazil, which want to postpone decarbonization efforts in the sector until the second half of this century. They have not set specific targets for emissions in shipping. Rogelj J, Forster PM, Kriegler E, Smith CJ, Seferian R. Estimate and track the rest of the carbon budget for strict climate targets. nature. 2019;571(7765):335–42. This study provides a new assessment of the scale of the climate change agenda for the shipping sector and the need to significantly accelerate efforts to implement a targeted CO2 policy within the existing global fleet. Based on Tong et al.
, we have recently analysed CO2 data for EU vessels that have sectoral data on ship life and estimate that the emissions promised for this EU dataset are twice as high as in their study.