In efforts to lower the amount of carbon dioxide in the atmosphere, a seemingly odd idea has been getting traction recently. It’s the idea of burying trees and other woody biomass deep underground to lock away the carbon in the biomass.
Researchers from the University of Cambridge and the Czech Academy of Sciences are now taking this idea to the Arctic Ocean floor. They propose the concept of sinking timber from the boreal forest to the oxygen-deprived deep Arctic Ocea floor to pack away carbon dioxide for a long time.
Some studies estimates that we will need to remove and sequester over 10 billion metric tons of carbon dioxide each year over the 21st century to combat the warming effects of human greenhouse gas emissions.
Wood vaulting involves burying woody biomass in enclosures that prevent the biomass from decomposing under oxygen-free or frozen conditions. Studies have shown that this could ideally sequester carbon on multi-millennial timescales. Thousands of large vaults would need to be constructed to sequester a meaningful amount of carbon.
In a new study published in the journal npj Climate Action, Ulf Büntgen and colleagues consider a simpler idea. They explore the potential of sinking boreal biomass to the ocean floor as a viable wood-vaulting alternative. For that, they consider the natural behavior of driftwood from the boreal forest and the stability of biomass in the deep ocean.
The boreal forest stretches across northern North America and Eurasia, from Alaska and northern Canada through Scandinavia and across Siberia. The region is characterized by its cold climate, slow-growing conifer trees, peatlands, permafrost soils, and vast river systems. And the boreal’s trees, dead woods, soils and peat store almost 1,000 billion metric tons of carbon.
Much of this biomass in the form of driftwood flows through rivers into the Arctic ocean, where it floats for a while before sinking. Büntgen and colleagues have looked into what happens to this wood after it sinks. In a paper published last year, measured 200 living and dry-dead trees from different cold, oxygen-rich and oxygen-free environments in the European Alps. They found no decline in cellulose content over the past 8000 years.
Not only are boreal conifer trees carbon-rich and economically unimportant, they have short transit routes to large river systems, the team concludes. This warrants “further exploration of the potential of harvesting and rafting large quantities of boreal timber into the Arctic Ocean for CO2 removal and multi-millennial scale storage,” the team writes. “The cold Arctic Ocean could store vast quantities of carbon from Siberia and northern North America where biodiversity is low and the risk of wildfires high.”
Source: Ulf Büntgen et al. Arctic driftwood proposal for durable carbon removal. npg Climate Action, 2026.
Image: AI-generated
