The International shipping and transport sector is vital for the global economy, but also contributes significantly to climate change due to greenhouse gas emissions and air pollution. According to the International Energy Agency (IEA), transport emissions from international shipping accounted for about 2% of global energy and transportation-related carbon dioxide emissions in 2021. Reducing emissions from international shipping and road transport is critical to meeting global climate goals. This will require a shift away from fossil-based fuels to low or zero-carbon alternatives, as well as technological innovation to improve efficiency and performance.

Smoke exhaust gas emissions from a large cargo ship — *Emissions from international shipping accounted for about 2% of global energy and transportation-related carbon dioxide emissions in 2021*

Reducing Transportation Emissions: Strategies to Meet Global Climate Goals and the Impact of the Paris Climate Agreement

As the Paris Climate Agreement requires, the maritime industry must adopt low- and zero-carbon fuels and technologies for oceangoing vessels to achieve net-zero transportation emissions by 2050. One of the measures that can help address carbon dioxide emissions from international shipping is “Slow Steaming”, which means operating ships at lower than their maximum design speed. Slow steaming can reduce fuel consumption and CO2 emissions by up to 30%, depending on the ship type and speed reduction. Slow steaming also has other benefits, such as lower maintenance costs, improved safety, and reduced noise and vibration. However, it also has challenges, such as longer transit times, higher capital costs for new ships, and potential impacts on cargo quality and supply chains.

International Shipping and Greenhouse Gas Emissions

International shipping has become one of the major contributors to global greenhouse gas (GHG) emissions, accounting for about 2% of global energy-related CO2 emissions in 2021. This is largely due to the burning of fossil fuels such as marine diesel, which produces carbon dioxide emissions (CO2), nitrous oxide emissions (N2O), and methane emissions (CH4). With global temperatures rising at an alarming rate, it is essential that steps are taken to reduce GHG emissions from the maritime sector. The IEA targets that low-carbon fuels should represent about 15% of international shipping’s total energy demand by 2030 and almost 100% of total transportation sector emissions, by 2050 in order to achieve net-zero global transport emissions by mid-century.

A thermometer in the sky, showing a hot temperature. Temperatures globally are rising due to climate change. — *With global temperatures rising at an alarming rate, it is essential that steps are taken to reduce GHG emissions from the maritime sector*

International Maritime Organization Regulations on the Transportation Sector & Carbon Dioxide Emissions

Another measure that can help address climate change by reducing emissions of greenhouse gases from the transportation sector is the implementation of the new regulations from the International Maritime Organization (IMO). These regulations limit the sulfur content of marine fuels to 0.5% by weight, down from the previous limit of 3.5%. The new regulations, known as IMO 2020, came into force on January 1, 2020, and aim to reduce sulfur oxide emissions from ships by 77%, an annual reduction of about 8.5 million tonnes. Sulfur oxide emissions harm human health and the environment, causing respiratory problems, acid rain, and ocean acidification. The new regulations also positively affect CO2 emissions, as low-sulfur fuels tend to have lower carbon intensity than high-sulfur fuels.

IMO 2020 Compliance Options for Maritime Industry: Pros and Cons

However, IMO 2020 also poses some difficulties for the maritime industry, such as higher fuel costs, availability and quality issues of low-sulfur fuels, and compliance and enforcement mechanisms. To comply with IMO 2020, ship owners and operators have three main options: switch to low-sulfur fuels such as marine gas oil (MGO) or very low sulfur fuel oil (VLSFO), install exhaust gas cleaning systems (EGCS) or scrubbers that remove sulfur from the exhaust gas before it is released into the atmosphere, or use alternative fuels such as liquefied natural gas (LNG), biofuels, hydrogen, or ammonia that have low or zero sulfur content.

Towards Zero-Emission Shipping: IEA’s Targets for Low-Carbon Fuels and Technological Innovation

While these measures can help reduce emissions from international shipping in the short term, they are not enough to achieve the long-term decarbonization goals of the transport sector. According to the IEA, low-carbon fuels must represent about 15% of total energy demand in international shipping by 2030, and almost 100% by 2050, to align global transport emissions with the net-zero scenario. This will require technological innovation, supportive policies, and collaboration across the transportation sector to enable the development and deployment of zero-emission oceangoing vessels.

A cargo container ship makes its way across the atlantic ocean as the sun rises. — *The maritime transportation industry will need to embrace more radical changes to adequately address climate change and ensure a sustainable future for itself and the planet.*

International Shipping Must Embrace Radical Changes for a Sustainable Future

In conclusion, international shipping is facing a significant transformation to reduce its carbon footprint and global emissions and comply with the global climate agenda. Slow steaming and IMO low sulfur fuel standards are two important measures that can help achieve this goal in the near term, but they are insufficient in the long run. The maritime transportation industry will need to embrace more radical changes in fuel choice, freight transport, and vessel design to adequately address climate change and ensure a sustainable future for itself and the planet.

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