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Reforesting as climate change mitigation

July 2019: A recent report highlights that planting 1 trillion trees on 0.9 billion-hectare land could substantially increase carbon capture. In comparison to other mitigation strategies, reforesting programmes are the cheapest and most efficient approach.


Corroborating recent reports promoting natural climate solutions, new evidence suggests that planting trees on 0.9 billion hectares of land worldwide could ultimately capture two thirds of human-made carbon emissions and become one of the most effective methods of combating climate change. The study identified 0 land across the globe that could be suitable for reforestation at this scale, including grazing lands currently used for sheep and cattle farming, excluding urban spaces or current crop land. US, Canada, Australia, Brazil, and China currently show the greatest potential for reforestation.

Implications & Opportunities

Forest restoration programmes could deliver storage capacity for approximately 205 billion tonnes of carbon at a cost or £240bn,  which is more cost-effective than other climate mitigation strategies.. However, trees will only realise their full carbon storage potential in 50-100 years and require expansion of agro-forestry into grazing lands currently used for meat and dairy production.


The study is a theoretical study determining the carbon storage potential for planting trees on a global level but does not address how a global tree planting programme could be delivered or financed and should therefore be seen within the context of these constraints. In particular, it does not consider the socio-economic implications of the sectors that will be displaced by the change in land use.


Bastin, J.-F., (2019). The global tree restoration potential. Science. 365 (6448), 76.

DOI: 10.1126/science.aax0848

The Guardian. (2019). Tree planting “has mind-blowing” potential to tackle climate crisis. Retrieved from

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Adele Wiliams

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