Growing more trees is one of the most efficient ways to absorb carbon emissions, researchers at Oxford University’s Smith School of Enterprise and Environment have found.

The researchers compared the potentials of a range of emissions abatement approaches including geo-engineering, carbon capture and storage, adding lime to the world’s oceans, reforestation and afforestation, soil carbon improvements and the use of biochar – created from burning wood waste at low temperatures – as a soil additive.

Afforestation, biochar and soil carbon proved to be the most workable and achievable methods. They are termed “no regrets NETs [negative emissions technologies]” by the research team, as they have low upfront capital costs, co-benefits such as enhanced soil fertility, no dependence on experimental technology, offer economic and environmental co-benefits and have fewer uncertainties than the other options canvassed.

The working paper stated they were the “most promising” NETs that could be implemented between now and 2050, as all other approaches were either in experimental or theoretical stage, extremely expensive or logistically unworkable if abatement is to be achieved within a timeframe that can limit global warming to two degree centigrade.

The research was undertaken as part of the institution’s stranded carbon assets research program.

The full working paper on stranded assets and negative emissions technologies is available here.