Sinking trees into the Arctic Ocean might reduce carbon emissions

A modelling study proposes removing mature boreal trees, floating them down Arctic rivers and sinking them in deep Arctic waters while replanting fast‑growing trees; the authors estimate this could sequester about one gigaton of CO2 per year if done on roughly 1% of the boreal forest. The article notes major logistical, ecological and social uncertainties and compares the potential removal with global emissions of 37.8 gigatons in 2024.

Researchers have proposed sinking mature boreal trees in the deep Arctic Ocean to lock away their carbon for long periods. The team, based in the UK, Switzerland and the Czech Republic, used computer modelling published in npj Climate Action to explore removing old, fire‑prone stands in parts of Canada, Alaska and Russia and transporting logs down rivers such as the Yukon and Mackenzie. The plan includes planting new, fast‑growing trees in place to accelerate carbon uptake. The concept is partly informed by discoveries of 8,000‑year‑old trees preserved in low‑oxygen lakes, which suggest cold, oxygen‑poor water can slow decay. Key facts: - The modelling indicates that removing trees from three areas of about 10,000 square kilometres each (roughly 1% of the boreal forest) could remove about one gigaton of CO2 per year if done annually. - The proposal focuses on boreal stands in Canada, Alaska and Russia and on moving wood down six Arctic rivers, including the Yukon and Mackenzie. - The researchers cite preserved ancient trees in low‑oxygen lakes as a reason to expect long‑term preservation in cold Arctic waters. - Practical concerns identified include the energy and emissions required for logging, transport and sinking, the strong natural buoyancy of wood (which can delay sinking), and interactions with sea ice. - The article raises ecological and social concerns, including impacts on forest biodiversity and fungal networks described by ecologist Suzanne Simard, unknown effects on seafloor organisms, and impacts on Indigenous ways of life. - The idea is presented alongside other geoengineering concepts and is compared with global emissions, noted as 37.8 gigatons of CO2 in 2024, making the potential removal proportionally small. Summary: The study presents a theoretical pathway to lock carbon in deep Arctic waters but faces large logistical, ecological and social uncertainties. Undetermined at this time. The article emphasizes that the potential one‑gigaton removal is small compared with 2024 global emissions of 37.8 gigatons.