To meet the goals of the Paris Agreement, experts say the world must invest in removing carbon from the atmosphere in addition to cutting emissions. But that can be a tall task as crucial carbon sinks -- such as plants, ocean, and soil -- fall victim to human activity and rising temperatures. The UK is facing this challenge head-on and has launched a series of carbon sequestration trials using trees, peat, rock chips, and charcoal. If successful, the trials could guide other countries in building and renewing carbon sinks across the globe.

Why This Matters

Carbon sinks are declining worldwide. Ocean stratification and acidification are destroying the ocean's ability to store carbon, while deforestation and worsening wildfires are releasing billions of tons of carbon into the atmosphere each year. Despite many nations, including the US, pledging to protect all lands and waters by 2030, advocates push for more significant commitments to carbon sinks, including old-growth forests and peatlands. Experts say that preserving carbon sinks reduces net emissions, and also lowers temperatures, supports biodiversity, and supports local communities. The UK's investment into various carbon sequestration methods could provide paths to many of the world’s environmental goals.

For Peat's Sake

The trials include investments into several different sequestration methods. Peatlands, if left undisturbed, sequester CO2 and have a long-term net cooling effect that can last thousands of years. The trials will rewet and replant peatlands in the Pennines and West Wales, where decades of farming, irrigation, and runoff left them ineffective at storing carbon. Restored peatlands could hold up to 10 tons of CO2 equivalent per hectare per year and prevent 30 tons of carbon emissions. Rock chips that absorb carbon as they break down will be tested in Devon, Hertfordshire, and mid-Wales, while unique "biochar" charcoal will be buried at special sites like a sewage disposal site, former mines, and railway embankments.

"This is seriously exciting and pretty much world-leading," said Cameron Hepburn, a professor at the University of Oxford who is leading the trials. "Nobody wants to be in the situation of having to suck so much CO2 from the atmosphere. But that's where we are -- we've delayed [climate action] for too long." Like many places in the US, the UK will also evaluate how facilitating new large-scale tree growth can offset its carbon footprint. The tree-planting trial is predicted to store 13 tons of CO2 equivalent per hectare per year. Additionally, there will be significant investments in crops such as willow and miscanthus grass that can be burned for energy while trapping emissions underground.

Experts estimate that the UK will have to remove 100 million tons of CO2 each year by 2050 to reach net-zero emissions, in addition to cutting new emissions. The trials are just one part of a more extensive £110m government program that will invest in advanced technology to remove even more carbon from the atmosphere. The trials' leaders are confident they will see success. "You can start now, you just need land and plants," said University of Exeter Professor and trial leader Ian Bateman. "There is huge potential to make an immediate difference towards the goal of net-zero by 2050."