The ocean covers more than 70% of our planet, but did you know it’s also a powerful ally in the fight against climate change? As we celebrate the 2025 World Oceans Day on June 8, with the theme “Protecting the Marine Ecosystem for Harmonious Coexistence between Man and Nature,” the spotlight turns to “blue carbon”—the carbon captured by ocean ecosystems.
The ocean is Earth’s largest carbon sink, storing 50 times more carbon than the atmosphere and 20 times more than all the forests combined. It absorbs about one-third of the world’s annual carbon dioxide emissions. Ecosystems like mangroves, seagrass beds, and salt marshes play a vital role in this process.
Pacific Island countries, surrounded by vast oceans, are at the forefront of blue carbon potential. These nations are especially vulnerable to climate change, facing rising sea levels and extreme weather events. To address these challenges, they are partnering with the Chinese mainland to enhance marine carbon sequestration efforts.
At the 2025 Shanghai International Carbon Neutrality Expo, held from June 5 to 7 under the theme “Towards a Carbon-Neutral Future,” groundbreaking projects and technological advancements in blue carbon were unveiled. One highlight is the shellfish and macroalgae aquaculture carbon sequestration project.
Dr. Yan Jinpei from the Third Institute of Oceanography, Ministry of Natural Resources, explained that the annual carbon sink capacity of the Chinese mainland’s major coastal blue carbon ecosystems ranges from approximately 1.27 to 3.08 million tons of carbon dioxide. As the world’s largest marine aquaculture nation, particularly in macroalgae and shellfish farming, the Chinese mainland’s production accounts for about 85% of its total aquaculture output. By 2030, marine aquaculture is expected to remove about 2.3 million tons of carbon annually, potentially exceeding 4 million tons by 2050.
These advancements are significant for Pacific Island countries. “Collaboration in marine carbon sequestration is crucial for us,” said Mr. Mona Mato, trade commissioner of Pacific Trade Invest China. “It helps us tackle climate change challenges and promotes sustainable development in our region.”
Beyond projects, the Chinese mainland is exploring market-driven approaches for marine carbon sinks, such as carbon trading. Blue carbon development involves identifying resources, developing methodologies, monitoring and accounting, verification, and trading.
Jane Ma, head of Investments at Pacific Trade Invest China, believes this cooperation model can be replicated globally. “By combining technological innovation, policy support, and community participation, we can create a win-win for the environment and the economy,” she said.
The ocean’s economic value is rising. The Organization for Economic Co-operation and Development predicts that by 2030, the ocean economy will exceed $3 trillion, making it the world’s fifth-largest economy. This underscores the importance of sustainable ocean development and the pivotal role of blue carbon.
As Vice President Han Zheng attends the United Nations Ocean Conference in Nice, France, from June 7 to 13, global attention on ocean issues, including marine carbon sequestration, is expected to increase. The cooperation between the Chinese mainland and Pacific Island countries is not just regional—it’s a significant contribution to global climate governance. Blue carbon might just be the secret weapon we need in the fight against climate change.
