Korea's dried seaweed went global. Now, it's going green

Korea Herald

5 days ago

Seaweed-based climate strategy tackles two goals: carbon absorption, climate-resilient agriculture
Among South Korea's ocean bounty, one standout is seaweed, most iconically in its dried form, known in Korean as "gim."
While many Koreans now take quiet pride in seeing this humble staple elevated to a global delicacy, only a handful have considered its promise beyond the plate.
Seaweed, after all, is giving back to the very waters that once gave it life -- as a source of climate solutions now taking root in Korea.
Seaweed as 'blue carbon'
According to the World Bank's 2023 Global Seaweed Markets Report, seaweed is a powerful climate ally -- a form of "blue carbon" in ocean and coastal ecosystems capable of sinking carbon and supporting biodiversity.
The report highlights 10 emerging markets, such as bioplastics, animal feed and nutraceuticals, that are projected to grow by $11.8 billion by 2030. Most farmed seaweed is still used for food or aquaculture, with 98 percent of global supply produced by a few Asian countries, Korea among them.
As the world's third-largest producer of seaweed and the top exporter of gim, Korea is turning its attention toward the algae's environmental promise.
One of the Ministry of Oceans and Fisheries' key initiatives is the creation of underwater ecosystems densely populated with seaweed species, known as "sea forests."
According to the Korea Fisheries Resources Agency, over 347 square kilometers of these sea forests have been created since 2009, now absorbing around 117,000 metric tons of carbon dioxide annually.
The ministry has set targets to increase Korea's blue carbon absorption to 1.07 million tons by 2030 and 1.36 million tons by 2050.
'Sea forests, once valued mainly as sources of food and shelter for marine life, are now being recognized for their strong carbon absorption capacity,' a ministry official said. 'We are working to secure international blue carbon certification to acknowledge their role in climate mitigation.'
Seaweed already meets five of the six core criteria for international recognition, with the final step, formal inclusion in the Intergovernmental Panel on Climate Change's greenhouse gas inventory guidelines, currently under review. The IPCC currently recognizes mangroves, salt marshes and seagrasses as official blue carbon ecosystems.
The country is further institutionalizing its ambitions, with the National Marine Biodiversity Institute of Korea set to build its own blue carbon research center by 2028.
Elsewhere, Wando-gun in South Jeolla Province -- Korea's largest seaweed-producing region -- has become a focal point in global blue carbon discussions.
In November last year, the local government visited the National Aeronautics and Space Administration in the United States to hold working-level discussions on advancing seaweed's blue carbon certification.
In 2021, NASA highlighted Wando by releasing satellite images and praising the region's sustainable farming practices as ideal for seaweed-based carbon mitigation.
'I asked NASA to help highlight the role of Wando's seaweed farms so that seaweed can be officially certified as blue carbon,' said County Mayor Shin Woo-chul after the visit, adding that the US agency expressed support for the initiative.
The local government is also collaborating with the US Department of Energy's Advanced Research Projects Agency–Energy on a joint Korea-US project, running through 2029, to develop offshore seaweed farming systems for large-scale biomass production and blue carbon advancement.
Gim reinvented
Alongside efforts to fight climate change with seaweed, adapting to its impacts is equally crucial.
Over the past 55 years, surface temperatures in Korean waters have risen by 1.36 degrees Celsius, shortening the duration of the gim harvest. In 2023, output in South Jeolla Province, home to 80 percent of Korea's production, fell 15 percent on-year.
In response, Korea is investing in next-generation aquaculture.
In May, the Oceans Ministry selected a consortium, including Goheung County Office in South Jeolla Province, several universities, and companies to develop gim seed strains for year-round production and establish quality-controlled farming systems in artificial marine environments. The project, backed by 35 billion won ($25.2 million) in national funding, runs through 2029.
Korean companies have already been working to bring land-based gim farming to life.
Food and biotech giant CJ CheilJedang, with the goal of commercializing the technology by 2028, became the first in the country to secure a gim variety specifically for land-based farming in 2023.
Daesang, another major food company, launched a pilot project for land-based farming in 2023, successfully growing its gim harvest to marketable size, while Pulmuone began operating land-based gim research facilities in 2021.
'Pulmuone's land-based gim cultivation takes place in bioreactors, which simulate ocean-like conditions to grow and harvest seaweed,' a Pulmuone official said. 'We currently produce 10 kilograms of gim per month and plan to launch a range of products, including seasoned gim, by 2027.'
Experts anticipate that new methods of gim cultivation could become the industry's dominant production model within the next decade.
'Land-based gim cultivation represents more than a production shift,' said Na Jung-ho, a senior researcher at the Jeonbuk Institute. 'It is a strategic pivot with the potential to restructure the industry and redefine national fisheries policy.'