Strategically planting trees along the northern edge of Canada’s boreal forest could remove multiple gigatonnes of carbon dioxide from the atmosphere by the end of the century, according to a new study led by researchers at the University of Waterloo. The research, published in Communications Earth & Environment, provides one of the most detailed estimates to date of the carbon that could realistically be sequestered through reforestation and afforestation in northern Canada, accounting for fire, climate, vegetation loss, and land suitability. Using satellite data and probabilistic modelling, the researchers found that planting trees on approximately 6.4 million hectares of land along the boreal–taiga boundary could remove roughly 3.9 gigatonnes of CO₂ by 2100. Expanding planting to all highly suitable areas increased the estimated removal potential to around 19 gigatonnes. Canada currently emits just under 0.7 gigatonnes of CO₂ per year, meaning even the lower-end estimate represents several times the country’s annual emissions.

• In related coverage by Live Science: Canada could remove 5 times its annual carbon emissions by planting trees on edge of boreal forest, study finds