WNAM REPORT: The Japanese government will launch offshore “blue carbon” research aimed at capturing carbon dioxide through cultivated sea plants and storing it in the deep sea to accelerate decarbonization, sources familiar with the matter said Monday.
The government hopes these plants will play a key role in mitigating climate change, as CO2 is highly soluble in water, and marine vegetation grows by absorbing dissolved CO2. Coastal and ocean plants, such as mangroves and kelp, are known to absorb and store more carbon than terrestrial vegetation.
Blue carbon typically refers to carbon trapped in the deep sea after being captured by marine ecosystems through photosynthesis, while green carbon refers to carbon stored in terrestrial ecosystems such as forests.
The Environment Ministry will commission the Japan Agency for Marine-Earth Science and Technology, major oil distributor Eneos Corp., and others to study how seaweed behaves when submerged at considerable depths and to assess the environmental impact of such carbon capture and storage projects, according to the sources.
Although CO2 emissions in Japan have declined mainly due to the expansion of renewable energy and the restart of nuclear reactors, the government still needs to boost carbon capture efforts to achieve net zero emissions by 2050.
Japan relies heavily on forests to capture CO2, with about 45 million tons absorbed in fiscal 2023. However, their absorption capacity has been declining due to the aging of trees.
“If we can demonstrate a technology to enable CO2 fixation on the seafloor, it could be a significant source of (CO2) absorption,” a senior official of the ministry said.
Japan aims to capture 1 million tons of CO2 by fiscal 2035 and 2 million tons by fiscal 2040 through blue carbon, compared with some 34 tons absorbed by coastal plants in fiscal 2023.