In Japan, efforts are underway to restore "konbu" kelp beds and use them to absorb carbon dioxide, combating climate change and providing additional benefits like improving fisheries resources and seawater quality. These initiatives involve partnerships between organizations like the Japan Blue Economy (JBE) Association and companies like Nippon Steel Corp., with a focus on capturing carbon through seaweed and seagrass to trade blue carbon credits under a newly introduced system. These credits, called J Blue Credits, are being issued based on the amounts of CO2 absorbed through the restoration projects, allowing operators to raise funds by selling them to enterprises looking to offset their carbon footprints.

One successful project in Mashike, northwestern Hokkaido, involves burying iron slag generated from steel production in coastal areas to supply iron to the sea for the growth of "konbu" kelp. This initiative has led to a significant increase in the area of the seaweed colony, resulting in benefits like higher sea urchin catch and increased incomes for the local fisheries cooperative association. Inspired by this success, similar efforts have been implemented in over 50 locations nationwide, including programs like transplanting eelgrass seedlings and developing tidal flats to grow marine plants like sea lettuce. Additionally, initiatives are underway in Hokkaido to measure blue carbon at production areas of famous seaweed varieties like Hidaka Konbu and Rishiri Konbu.

While efforts to evaluate the effects of blue carbon are ongoing, Japan is taking the lead in establishing methods to estimate the carbon absorption of aquatic plants like seaweed and seagrass on a national scale. The Japanese government is using satellite images, geographic features, water temperatures, and other factors to estimate the extent of seaweed colonies and develop a calculating method for CO2 absorption by different types of marine plants. Japan aims to present its blue carbon absorption details to the United Nations in April, positioning itself as a frontrunner in defining global criteria for blue carbon, with the estimated blue carbon footprint for fiscal 2022 standing at 360,000 tons.