According to ICCT, establishing a U.S. Monitoring, Reporting, and Verification (MRV) system would fill important data gaps in official U.S. maritime emissions estimates, align U.S. practices with the European Union, and enable the U.S. to track progress toward climate goals.
The ICCT brief finds that a U.S. MRV program could have covered approximately 11,100 ships that together emitted approximately 103 million tonnes (Mt) of carbon dioxide equivalent (CO2e) emissions on voyages to, from, or between U.S. ports. This total is higher than official U.S. estimates of maritime emissions.
Moreover, of the 103 Mt CO2e, 43% are from outbound voyages, 33% from inbound voyages, 14% from cabotage voyages, and 10% in ports. Similar to the European Union’s program, if half of the outbound and inbound emissions and all cabotage and in-port emissions were subject to a GHG price ranging from $70 (the EU MRV carbon price as of September 2024) to $230 per tonne of CO2e (EPA’s social cost of carbon estimate adjusted to 2024 dollars), the revenues could equal between $4.5 billion to $15 billion per year.
Container ships were responsible for the most emissions in 2022, accounting for more than 30 Mt CO2e, and were also responsible for the largest share of emissions of inbound and outbound voyages. Cruise ships were the second-highest emitting ship type, with 15 Mt CO2e of total emissions. Notably, cruise ships were the highest emitters for cabotage voyages.
In addition, tankers transporting LNG were the third-highest emitters in most voyage types (14 Mt CO2e), but the second-highest emitters for outbound voyages, reflecting U.S. exports of LNG. Together, container ships, cruise ships, and LNG tankers accounted for 58% of total emissions.
Bulk carriers ranked fourth in total emissions (13 Mt CO2e) and in cabotage voyages (1.3 Mt CO2e).
Other important ship types include oil tankers, which emitted 11 Mt CO2e in total, and chemical tankers, with emissions of about 10 Mt CO2e.
