Green credits are a system in which the country certifies the amount of CO2 and other emissions absorbed through proper forest management as credits. The price of these green credits is rising. In particular, the rate of increase in the credit price of afforestation projects aimed at absorbing carbon dioxide is high. Companies have emissions that they cannot reduce in order to achieve zero CO2 declarations. In order to offset these emissions, there is a trend to invest in afforestation projects that are relatively easy to manage. In contrast to these green credits, there are blue carbon credits. This is a system in which seaweed such as wakame and kombu and seagrass such as eelgrass absorb CO2 in the water and then store it on the seabed for a long period of time. Japan is leading the way in creating blue carbon credits derived from seaweed.
The United Nations Environment Program states that blue carbon ecosystems such as seaweed beds and tidal flats can be used to combat global warming. The carbon storage period of seaweed and other organisms is said to be hundreds to thousands of years at most, which is longer than that of forests, which lasts for several decades. Japan is an island country surrounded by the sea. Japan may be a small country, but there is a lot of room for blue carbon. Although the country is small, it ranks sixth in the world in both coastline length and ocean area. Phytoplankton, which is a type of algae, grows quickly, reproduces quickly, and dies quickly, which is a characteristic of this marine producer. Phytoplankton divides once every six days. Half of this phytoplankton is destined to die or be eaten by other organisms. The entire amount of phytoplankton is replaced once a week. This means that the generational change in the ocean is proceeding about 260 times faster than on land.
According to the Port and Airport Research Institute under the Ministry of Land, Infrastructure, Transport and Tourism, the amount of CO2 absorbed by land in the world is 7.7 billion tons per year. On the other hand, the amount of blue carbon absorbed in the ocean is 10.2 billion tons, which is more than on land. There is still potential in the ocean. There is also a movement in Japan to sell the amount of CO2 reduced by blue carbon as credits. Moreover, it is being traded at a high price. The Japan Blue Economy Technology Research Association (JBE), an organization approved by the Minister of Land, Infrastructure, Transport and Tourism, is trading at a price more than five times higher than forest credits. JBE is a certification organization for blue carbon credits. The issuance record of these credits is over 2,000 tons in fiscal year 2023.
