Blue Growth Potential to Mitigate Climate Change through Seaweed Offsetting

Area of Science:

• Marine biology and climate science
• Aquaculture and carbon sequestration technologies
• Environmental policy and sustainable development

Background:

• Carbon offsetting is crucial for climate change mitigation, with land-based solutions facing limitations.
• Seaweed aquaculture presents a growing alternative for carbon sequestration due to its scalability.
• The food sector is a significant contributor to greenhouse gas emissions, necessitating innovative solutions.

Purpose of the Study:

• To assess the potential of seaweed aquaculture for carbon dioxide (CO2) sequestration.
• To evaluate the feasibility and cost of scaling seaweed farming for climate change mitigation.
• To explore the co-benefits of seaweed farming for coastal ecosystems.

Main Methods:

• Synthesizing data from scientific literature on seaweed aquaculture potential.
• Analyzing ecological constraints such as nutrient availability and temperature.
• Modeling carbon sequestration capacity under various climate mitigation scenarios.

Main Results:

• Approximately 48 million km2 of suitable, largely unfarmed area exists for seaweed farming.
• Seaweed aquaculture could achieve carbon neutrality within its industry using a small fraction of suitable areas.
• Offsetting global agriculture via seaweed farming is unlikely due to scale and cost, but regional offsetting is feasible.

Conclusions:

• Seaweed farming is a viable tool for carbon offsetting, particularly at regional levels with supportive climate policies.
• It offers co-benefits like mitigating eutrophication, hypoxia, and ocean acidification.
• Seaweed aquaculture represents a valuable addition to the portfolio of climate change solutions, contributing to a sustainable future.