There are more solutions than obstacles. Nicolas Zart
Although we mostly focus on aviation and especially advanced air mobility (AAM), we wanted to talk about the appalling flight shaming. To put it into context, especially compared to other means of transportation systems that don’t receive the same amount of public scrutiny.
Historic IMO Net-Zero Framework and the Overlooked Realities of Transport Emissions
In April 2025, the International Maritime Organization (IMO) approved two critical policies aiming at cleaning up its emissions: the Net-Zero Framework for decarbonizing international shipping and the North-East Atlantic Emission Control Area (AtlECA), now the largest low-emission marine zone in the world. These measures aim to reduce annual maritime CO₂ emissions by up to 1 billion tonnes. Yet, while aviation remains the primary target of public scrutiny, the data reveals a more complex hierarchy of responsibility in transport emissions.
The Disproportionate Impact of Maritime and Road Transport
Aviation accounts for approximately 2.5% of global CO₂ emissions, a figure frequently cited in climate discussions. Although the number is low, its position high in the sky means it has a more global footprint than localized mobility emissions, such as the automotive industry and rail. However, this focus obscures larger contributors. Overall, the maritime shipping industry is responsible for 1,076 million tonnes of CO₂ annually, roughly 11% of global transport emissions. In other words, the maritime shipping industry emits more than most industrialized nations. A single large container ship can match the emissions of 76,000 passenger vehicles (Transport & Environment, 2023).
Road transport emissions led by SUVs and pick-ups, mainly light-duty trucks, contribute roughly 1,000 million tonnes of CO₂ a year, or 33% of all road transport emissions. This completely surpasses the entire aviation sector (IEA, 2024) with little to no news scrutiny.
The disparity in policy and public attention is striking. While aviation faces carbon pricing schemes and flight shaming, it isn’t uncommon to hear passengers wanting to take cruise ships across the oceans to reduce their carbon footprint, not realising they are increasing it exponentially. As of today, and unlike other industries, shipping has operated without a global carbon tax.
The IMO’s 2025 Net-Zero Framework: Key Components
The newly adopted framework establishes a structured approach to curbing and eventually eliminating shipping emissions by 2050. Its two primary mechanisms are:
- Greenhouse Gas Fuel Intensity Standard
A performance-based regulation requiring ships to progressively reduce emissions per unit of energy consumed. Compliance is assessed on a full lifecycle basis, from fuel production to combustion. - Economic Measures
A carbon pricing system that penalizes excess emissions while directing revenue into a Net-Zero Fund to support green maritime technologies. Ships outperforming targets may generate tradable credits.
Challenges Ahead
While the framework marks progress, its current targets fall short of aligning with the Paris Agreement’s 1.5°C threshold. Unaddressed issues, such as methane slip from LNG-powered vessels and unsustainable biofuel loopholes, could undermine its effectiveness.
The North-East Atlantic Emission Control Area (AtlECA)
Spanning 5 million square kilometers, the AtlECA goes beyond CO₂ and introduces stringent limits on sulfur and nitrogen oxides. Projected impacts include:
- An 82% reduction in sulfur oxides (SOₓ) and up to 71% less nitrogen oxides (NOₓ) by 2050.
- Prevention of an estimated 4,300 premature deaths and €19–29 billion in health cost savings (ICCT, 2025).
This initiative sets a precedent for future emission control areas in other heavily trafficked regions, such as the Pacific and Indian Oceans.
Why Aviation Dominates the Conversation—And Why That’s Misleading
Public discourse disproportionately singles out aviation despite its relatively modest emissions share. Like all vehicles, whether on rail, road, air, or water, is that vehicles use a lot of energy to pick up speed. Once in cruise mode, they become less power-hungry. The automotive problem relying on rubber tires on tar is one of constantly fighting against friction, a scenario made worse in water with hulls fighting to separate the ocean to split through. Overall, several factors contribute to this awareness imbalance:
- Visibility: Air travel is a consumer-facing industry, whereas shipping operates largely out of public view.
- Regulatory Asymmetry: Aviation has been subject to carbon pricing for over a decade (e.g., EU ETS, CORSIA), while maritime regulations have lagged.
- Media Narratives: High-profile campaigns like “flight shaming” simplify a complex issue, overshadowing larger polluters.
Meanwhile, SUVs emit 2.5 times more CO₂ per kilometer than standard passenger cars, according to the EPA, and face very minimal regulatory pushback outside Europe. The IEA notes that SUV sales growth between 2010 and 2022 offset all CO₂ reductions from electric vehicles in the same period.
Policy Implications and Future Directions
The IMO’s framework is an important step in the right direction for further efficiencies needed. Its success depends on addressing lingering gaps:
- Stricter Lifecycle Analysis: Closing loopholes for biofuels and synthetic fuels with high upstream emissions.
- Global Expansion of Emission Control Areas: Replicating the AtlECA model in other high-traffic zones.
- Cross-Sector Learning: Applying maritime’s carbon pricing mechanisms to aviation and road transport.
Global Emissions versus Efficiency
The decarbonization of international shipping represents one of the most consequential and underreported opportunities of this century. While the IMO’s new policies signal progress, their effectiveness hinges on rigorous implementation and broader policy alignment across transport sectors. For professionals in mobility and energy, the task is simple: become more efficient, save energy, lighten the emission burden on the planet, and reap more profits. Industries and entertainment news need to move beyond flight-shaming narratives and confront the larger challenges in maritime and road transport.
Will the IMO’s new policies accelerate the shift to zero-emission shipping? Share your thoughts below!
For further reading, see IMO’s meeting transcripts here.