These are the main conclusions of the Fourth IMO Study on Greenhouse Gases, prepared for the International Maritime Organization by an international consortium made up of ten consultancies, research institutes and universities from four continents and led by CE Delft (Netherlands) , in alphabetical order ClassNK (Japan), Dalian Maritime University (China), Fudan University (China), the Economic Research Institute Foundation, the University of São Paulo (Brazil), the International Council for Clean Transportation, the Manchester Metropolitan University (UK), the National Institute for Maritime Research, the National Institute of Maritime, Port and Aviation Technology (Japan), Purdue University (USA) and UMAS, University College London (UK). United).
- Greenhouse gas (GHG) emissions - including carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O), expressed in CO2e - from total shipping (international, domestic and fishing) have increased by 977 million tons in 2012 to 1,076 million tons in 2018 (9.6% increase). In 2012, 962 million tons were CO2 emissions, while in 2018 this amount grew by 9.3% to 1,056 million tons of CO2 emissions.
- The share of marine transport emissions in global anthropogenic emissions increased from 2,76% in 2012 to 2,89% in 2018.
- Under a new travel-based allocation for international shipping, CO2
have also increased during this same period from 701 million tonnes in 2012 to 740 million tonnes in 2018 (an increase of 5.6%), but at a lower rate than total emissions from maritime transport, and represent a growth rate a constant share of global CO2 emissions during this period (approximately 2%), as shown in Table 1. Using the IMO's ship-based allocation, CO2 emissions have been increased over the period from 848 million tons in 2012 to 919 million tons tons in 2018 (increase of 8.4%). - Due to the evolution of data and inventory methods, this study is the first IMO study on GHGs can produce greenhouse gas inventories that distinguish domestic shipping from international emissions on a voyage in a way which, according to the consortium, is exactly consistent with the IPCC guidelines and definitions.1
- Projecting the same method to 2008 emissions, this study estimates that GHG emissions from international shipping in 2008 (in CO2e) were 794 million tonnes (using the method used in the IMO's Third GHG Study, the were of 940 million tons of CO2e).
