Many scientists believe that the world is on the brink of climate disasters and urgently needs transformative counteractions. The ocean, as the largest active carbon sink on Earth, has played an irreplaceable role in regulating climate change. However, issues such as ocean acidification and biodiversity loss are directly affecting the ocean's carbon absorption capacity.
“How to protect and restore the ocean’s negative emission capacity has become an important direction in addressing climate change,” said Jiao Nianzhi, an academician of the Chinese Academy of Sciences (CAS) and chief scientist of Global Ocean Negative Carbon Emissions (Global-ONCE) program.
Ocean negative emissions refer to the process by which the ocean absorbs additional carbon dioxide from the atmosphere through a series of biological, physical, and chemical processes, and sequesters it in the ocean. It can be simply understood as allowing the ocean to "consume" more carbon dioxide from the air.
The known ocean carbon sequestration mechanisms include the solubility pump, the carbonate pump, and the biological pump. To apply these mechanisms to ocean-based negative emissions while protecting the marine ecosystem, people should take the priority to comprehensively understand the processes and mechanisms of ocean carbon sequestration.
China has a solid theoretical foundation in the research of ocean negative emission technologies. As early as 1991, Jiao pioneered in the research on new marine productivity, which is one of the few quantitative indicators in ocean carbon sink.
In 2010, Jiao was the first to propose the "microbial carbon pump" (MCP) carbon storage mechanism, unveiling the mystery behind the ocean's vast carbon storage. The Science magazine described the MCP as "the invisible hand behind a vast carbon reservoir" and published a special issue on the MCP.
The MCP and related theories on ocean carbon sink have been incorporated into China's national strategy for ecological civilization, the Intergovernmental Panel on Climate Change (IPCC) Special Report, and the Intergovernmental Oceanographic Commission (IOC) of UNESCO's report on ocean carbon.
In 2017, Jiao initiated the Global ONCE program, aiming to gather the wisdom of top scientists and engineers from around the world. The program also leverages the advantages of interdisciplinary integration to explore the processes and mechanisms of ocean negative emissions in depth and to develop a set of ocean negative emission solutions based on practical application scenarios for global promotion.
"We aim to achieve three goals: major theoretical innovations in ocean negative emissions; significant breakthroughs in technological applications; and leading the establishment of international standards to create a new paradigm for ocean negative emission ecological engineering," Jiao told the VOC during an interview at the 2024 World Science and Technology Development Forum held between October 22 and 24 in Beijing.
Currently, research teams from 33 countries have joined the Global ONCE program, and the program has proposed many ocean negative emission solutions.
For example, one solution plans to enhance carbon sequestration in aquaculture environments through clean energy-driven artificial upwelling that brings nutrient-rich water from the bottom of aquaculture areas to the surface. By supplying the nutrients needed for the photosynthesis of cultivated seaweeds, the solution addresses the mismatch in the supply and demand of nutrients, inorganic carbon, and dissolved oxygen and transforms "polluted areas" into "carbon sink areas", according to Jiao.
Research also found that feeding seaweed to ruminants can reduce methane emissions by up to 93 percent. Considering this, the livestock industry in western China can collaborate with the seaweed farming industry in eastern China by implementing the "seaweed farming in the east - cattle feeding in the west" industrial chain synergy strategy. It will form a new model of "domestic large circulation between the east and west" and achieve carbon reduction while enhancing carbon sequestration, Jiao said.
Jiao said that the Global ONCE program has been approved by the International Organization for Standardization (ISO) to establish a working group on ocean negative emissions and carbon neutrality. The main responsibility of the working group is to formulate and promote international standards in ocean negative emissions and carbon neutrality, providing scientific, normative, and practical guidance for ocean negative emission practices and carbon neutrality goals globally.
Jiao also stressed that it requires interdisciplinary research involving marine science, environmental science, ecology, economics, and engineering to promote breakthroughs in ocean negative emission technologies.
“Interdisciplinary cooperation model not only promotes the creation of new productive forces, but also provides new ideas for global sustainable development,” he said.
Addressing climate change and achieving global sustainable development are long-term and arduous tasks. The Global ONCE is not only a scientific exploration process, but also carries the expectations and responsibilities of all sectors of society for the protection of the shared future for mankind.
“I believe that through joint efforts, we will overcome many difficulties and jointly create a better, harmonious, and sustainable future,” Jiao said.
Source： VOC
