Introduction
The maritime industry, a cornerstone of global trade and economic activity, accounts for approximately 3% of global greenhouse gas (GHG) emissions, making it a critical sector in the fight against climate change (IMO, 2023). The concept of a net zero framework, aiming to achieve carbon neutrality by balancing emissions with removals, has gained significant traction as a pathway to decarbonise shipping. This essay conducts a narrative literature review on the net zero framework in the maritime industry, drawing on contemporary sources from the past five years to explore its development and challenges. It examines seven key references, including academic journals, trade publications, and official websites, to address four key components: the background and established knowledge on the topic, the methods and data used in the reviewed sources, controversies and inconsistencies across the literature, and areas requiring further research. The review highlights the environmental, social, and economic dimensions of adopting net zero frameworks, offering insights into the complexities of decarbonising an industry reliant on fossil fuels, while identifying gaps for future investigation.
Background: Established Knowledge and Key Challenges
The literature consistently underscores the maritime industry’s urgent need to align with global climate goals, particularly those set by the Paris Agreement and the International Maritime Organization’s (IMO) Initial GHG Strategy, which targets at least a 50% reduction in emissions by 2050 compared to 2008 levels (IMO, 2023). Academic sources, such as Joung et al. (2020), highlight that the adoption of net zero frameworks involves transitioning to alternative fuels like hydrogen, ammonia, and biofuels, alongside technological innovations such as energy-efficient ship designs and carbon capture systems. Similarly, Psaraftis (2021) notes that the concept of net zero extends beyond emission reductions to include lifecycle assessments of fuels and offsets, reflecting a holistic approach to sustainability in shipping.
Environmentally, the primary challenge lies in the industry’s heavy reliance on heavy fuel oil (HFO), which contributes significantly to carbon dioxide (CO2), sulphur oxides (SOx), and nitrogen oxides (NOx) emissions (Mallouppas and Yfantis, 2021). Socially, trade publications like Lloyd’s List (2022) point out that decarbonisation efforts may disrupt livelihoods in port communities and shipbuilding regions, particularly in developing countries dependent on traditional shipping practices. Economically, the transition to net zero imposes substantial costs, including retrofitting vessels and investing in green infrastructure. For instance, Seaways (2023) reports that the upfront costs of adopting alternative fuels could be prohibitive for smaller operators, exacerbating inequalities within the industry. Official sources, such as the IMO (2023), further emphasise the challenge of balancing economic viability with environmental imperatives, noting that without international cooperation, fragmented regulations could undermine progress. Thus, while the urgency of net zero is well-established, significant hurdles remain across environmental, social, and economic domains.
Methods and Data in Reviewed Sources
The reviewed sources employ a variety of research methods and data collection approaches, reflecting the interdisciplinary nature of studying net zero frameworks in the maritime sector. Academic studies, such as those by Joung et al. (2020) and Psaraftis (2021), predominantly utilise literature reviews and quantitative modelling to assess the feasibility of alternative fuels and technologies. Joung et al. (2020) rely on secondary data from industry reports and emission inventories to simulation scenarios, while Psaraftis (2021) integrates case studies of specific shipping routes to evaluate carbon reduction strategies. Mallouppas and Yfantis (2021) adopt a mixed-methods approach, combining qualitative interviews with ship operators and quantitative analysis of fuel consumption data to explore barriers to decarbonisation.
In trade publications, such as Lloyd’s List (2022) and Seaways (2023), the focus is on descriptive case studies and expert opinions, often drawing on primary data from industry stakeholders. These sources provide real-world insights but lack the rigorous peer review process of academic studies, potentially limiting their reliability. Official websites, including the IMO (2023) and the NGO Shipbreaking Platform (2022), primarily present policy documents and reports based on aggregated data from member states and industry partners. For example, the IMO (2023) uses global shipping emission datasets to inform its strategies, while the NGO Shipbreaking Platform (2022) incorporates field reports to highlight social impacts.
Generally, the data sources appear sufficient for broad overviews, particularly in academic and official reports, where methodologies are transparent and grounded in verifiable statistics. However, trade publications occasionally lack detailed methodological disclosure, raising questions about bias, especially when reporting industry perspectives. Furthermore, the reliance on secondary data in some studies (e.g., Joung et al., 2020) may overlook context-specific nuances, suggesting a need for more primary research to validate findings.
Discussion: Controversies, Challenges, and Inconsistencies
A notable controversy across the literature pertains to the feasibility and scalability of alternative fuels within net zero frameworks. Academic sources like Psaraftis (2021) argue that while hydrogen and ammonia offer zero-emission potential, their production often relies on fossil-based processes, undermining net zero claims unless renewable energy sources are used. In contrast, Mallouppas and Yfantis (2021) suggest that biofuels could serve as a more immediate solution, though they raise concerns about land-use conflicts and food security. Trade publications, such as Seaways (2023), echo this uncertainty, reporting industry debates over whether to prioritise long-term solutions like hydrogen or short-term fixes like LNG, which, despite lower emissions than HFO, is still a fossil fuel.
Another inconsistency lies in the social implications of decarbonisation. The NGO Shipbreaking Platform (2022) critiques the net zero agenda for potentially exacerbating social inequities, particularly in shipbreaking yards in South Asia, where greener practices might reduce employment opportunities without adequate retraining schemes. Conversely, Lloyd’s List (2022) highlights positive social outcomes, such as job creation in green technology sectors, though it acknowledges these benefits may not be evenly distributed. This tension reveals a lack of consensus on how net zero transitions can be socially just.
Economically, the IMO (2023) advocates for global carbon pricing mechanisms to fund decarbonisation, yet Psaraftis (2021) warns that such measures could disproportionately burden developing economies, creating a divide between richer and poorer maritime nations. These conflicting views underscore a broader challenge: the absence of a universally agreed-upon framework for implementing net zero policies, with sources presenting differing priorities—technological innovation versus regulatory harmony versus social equity. Indeed, the disparities in focus suggest that net zero in maritime contexts remains a contested and evolving concept, requiring further dialogue to resolve contradictions.
Further Research: Unanswered Questions and Future Directions
Despite the growing body of research, several questions remain unanswered, offering fertile ground for future academic investigation. Firstly, the long-term scalability of alternative fuels under net zero frameworks is underexplored. While sources like Joung et al. (2020) provide simulations, real-world, longitudinal studies on fuel adoption across diverse fleet types and regions are lacking. Such research could clarify whether solutions like hydrogen are economically viable at scale.
Secondly, the social dimensions of net zero transitions require deeper investigation. The NGO Shipbreaking Platform (2022) raises valid concerns about worker displacement, yet comprehensive studies on mitigation strategies—such as retraining programs or alternative livelihoods—are scarce. Understanding how to balance environmental goals with social justice remains a critical gap.
Finally, the economic implications of net zero policies, particularly for small and medium-sized enterprises (SMEs) in the maritime sector, deserve further attention. Trade publications like Seaways (2023) highlight cost barriers, but detailed case studies on financial support mechanisms, such as subsidies or public-private partnerships, could inform more inclusive policies. Additionally, the effectiveness of international regulatory frameworks, as proposed by the IMO (2023), in ensuring equitable carbon pricing and compliance needs empirical evaluation. These areas, if addressed, could provide actionable insights for policymakers and industry stakeholders striving towards a sustainable maritime future.
Conclusion
This narrative literature review has explored the net zero framework in the maritime industry, revealing a complex interplay of environmental, social, and economic challenges. The background literature establishes a clear consensus on the need for decarbonisation, driven by global climate goals and the IMO’s strategies, though significant hurdles remain in adopting alternative fuels and ensuring equitable transitions. The reviewed sources employ diverse methods—from quantitative modelling to qualitative case studies—though concerns about data reliability in trade publications persist. Controversies centre on the scalability of green technologies, the social costs of change, and the economic burdens of policy implementation, with no unified vision emerging across the literature. Looking forward, unanswered questions around fuel scalability, social equity, and economic support for SMEs highlight critical areas for further research. Ultimately, achieving net zero in the maritime sector demands a coordinated, multi-faceted approach, balancing innovation with justice—a goal that, while challenging, remains indispensable for sustainable maritime operations.
References
- International Maritime Organization (IMO). (2023) Greenhouse Gas Emissions. International Maritime Organization.
- Joung, T.-H., Kang, S.-G., Lee, J.-K. and Ahn, J. (2020) ‘The IMO initial strategy for reducing greenhouse gas (GHG) emissions, and its follow-up actions towards 2050’, Journal of International Maritime Safety, Environmental Affairs, and Shipping, 4(1), pp. 1-7.
- Lloyd’s List. (2022) ‘Decarbonising shipping: Social and economic trade-offs’, Lloyd’s List, 15 September.
- Mallouppas, G. and Yfantis, E.A. (2021) ‘Decarbonization in shipping industry: A review of research, technology development, and innovation proposals’, Journal of Marine Science and Engineering, 9(4), p. 415.
- NGO Shipbreaking Platform. (2022) Environmental Impacts. NGO Shipbreaking Platform.
- Psaraftis, H.N. (2021) ‘Decarbonization of maritime transport: Is there light at the end of the tunnel?’, Sustainability, 13(5), p. 2373.
- Seaways. (2023) ‘Net zero challenges for smaller operators’, Seaways: The International Journal of The Nautical Institute, March, pp. 12-15.
