Argentina deposited the instrument of accession to MARPOL Annex VI on 8 June 2021 and became the 100th State Party to Annex VI, which now covers 96.65 per cent of world merchant shipping by tonnage.

The IMO’s Marine Environment Protection Committee (MEPC 76), meeting from 10 to 17 June 2021, adopted amendments to the International Convention for the Prevention of Pollution from Ships (MARPOL) Annex VI that will require ships to reduce their greenhouse gas emissions. All ships will be required to calculate their Energy Efficiency Existing Ship Index (EEXI) following technical means to improve their energy efficiency and to establish their annual operational carbon intensity indicator (CII) rating. Carbon intensity links the GHG emissions to the amount of cargo carried over distance travelled. Ships will get a rating of their energy efficiency (A, B, C, D, E, where A is the best). A ship rated D for three consecutive years, or E, is required to submit a corrective action plan, to show how the required index (C or above) would be achieved.

The amendments to MARPOL Annex VI (adopted in a consolidated revised Annex VI) will enter into force on 1 November 2022, with the requirements for EEXI and CII certification coming into effect from 1 January 2023. The first annual reporting will be completed in 2023, with the first rating given in 2024. A review clause requires the IMO to review the effectiveness of the implementation of the CII and EEXI requirements, by 1 January 2026 at the latest, and, if necessary, develop and adopt further amendments.

The MEPC also adopted related guidelines to support the implementation of the amendments. The guidelines include the 2021 Guidelines on the operational carbon intensity reduction factors relative to reference lines (CII Reduction factor Guidelines, G3). This includes the required reduction (Z) factor, which is set at a rate, relative to 2019,