Seaweed farming and Blue Carbon: another path in climate mitigation

Japan’s seaweed farming is gaining attention for its vital potential in combating climate change. As a candidate of “blue carbon,” seaweed is a naturally stored form of carbon in coastal ecosystems, as a means to reduce atmospheric carbon dioxide.

Blue carbon typically refers to the carbon captured by mangroves, seagrasses, and salt marshes. Recent attention, however, has turned to the carbon sequestration potential of seaweed, like nori and kelp, which is integral to Japanese cuisine and cultural heritage. During its rapid growth phase, nori absorbs significant quantities of CO₂, offering an environmentally friendly method of carbon capture that complements traditional blue carbon strategies.

Being a long staple of local Japanese communities, perhaps it’s time to find a spot for Japanese seaweed farming, not only for the role of mitigating greenhouse gas emissions, but also for a seat for cultural preservation and sustainable development.

Yokohama’s Sachiumi Heroes is one of the best examples of this. Their kelp farming bolster local economy, support traditional practices, promote a circular economy, and develop resource efficiency. All these provide both environmental and social gains. (Not to mention cultural benefits where they are trying to find a way to use the kelp in hot springs!)

Experts suggest that initiatives like Sachiumi Heroes can serve as a model for coastal communities worldwide. They combine indigenous methods with modern sustainability frameworks, and can be retooled to address contemporary environmental challenges. Although further research is needed to fully quantify the carbon capture potential of seaweed cultivation, early indications are promising.

As we grapple with escalating climate challenges, Japan’s nori farming offers valuable insights into an combination of tradition and carbon negative efforts.