Marine life and coastal communities face dire threats, but in the midst of these challenges, the ocean emerges as a formidable ally in the fight against the climate crisis.
Seven ocean-based climate solutions have the potential to close up to 35% of the carbon emissions gap needed to keep the planet on track for 1.5℃ by mid-century.
Significant mitigation potential stems from the following areas, as outlined in the updated High Level Panel for a Sustainable Ocean Economy report:
Ocean-based renewable energy encompasses efforts to scale up offshore wind and investment in new technologies like floating solar panels, wave power, and tidal power. Up to 75% of anthropogenic greenhouse gas emissions can be considered the target for avoidance through electricity generation with renewable resources.
Decarbonizing ocean shipping and transport includes amplifying technologies to increase energy efficiency and support the development of low-carbon fuels, as part of a broader decarbonization of ocean industries and energy supply chains. In 2023, the UN’s International Maritime Organization (IMO) adopted a revised strategy to reach net-zero GHG emissions from shipping by 2050, requiring the implementation of technical and operational measures to support the phase-out of fossil fuels in domestic and international shipping.
Decarbonizing ocean-based tourism, focusing on cruise vessels and utilizing technological advances in marine transport. The cruise industry is particularly carbon-intensive and rapidly growing. While many major cruise lines have made commitments and long-term pledges to reduce their carbon intensity by 2050, many of these steps fall short of what’s needed.
Conservation of blue carbon ecosystems such as mangrove forests, salt marshes, and seagrass beds can prevent further release of greenhouse gas emissions. Studies have found that mangroves and other coastal wetlands store 3 to 5 times more carbon than a tropical rainforest of an equivalent area.
Sustainable aquaculture and fishing can contribute significantly to climate change mitigation by reducing the carbon footprint of ocean-derived food in ways such as reducing waste in the seafood supply chain and moving to low-carbon aquaculture feeds. The other mitigation gain comes from shifting diets away from emissions-intensive land-based sources of protein to sustainable marine options like fish, seaweed, and kelp.
Marine CO₂ removal and carbon capture and storage includes approaches like sequestration in the seabed, ocean alkalinity enhancement, direct ocean removal, and seaweed sequestration through active sinking and passive sequestration associated with seaweed farming. Focus must remain on further research and technology development, as well as considerations for policy and environmental safeguards.
Stopping the expansion of offshore oil and gas extraction to account for potential emissions avoided coupled with a demand-driven phase down of current production. The IPCC AR6 Synthesis Report (IPCC 2023) predicts that the carbon emissions from current fossil fuel infrastructure worldwide are likely to exceed the total emissions that would keep global warming within 1.5°C.
In addition to providing a new pathway to a climate-resilient future, ocean-based solutions offer a host of co-benefits, including economic growth, employment opportunities, biodiversity protection, and improved food security.
Until now, the ocean has too often been overlooked and underfunded — an underdog in the climate sector. These solutions must be prioritized to scale the global response to climate change.
