Carbon dioxide removal (CDR) is vital for limiting global warming to 1.5ºC. According to the Intergovernmental Panel on Climate Change (IPCC), human activities need to be actively removing 10 Gigatonnes of atmospheric CO2 annually by the year 2050 in order to have a chance at meeting this warming target set by the Paris Climate Accords. Recent research using large-scale models shows that in the UK alone, enhanced rock weathering has the potential to remove up to 30 million tonnes of CO₂ per year – enough to address 45% of the UK’s annual emissions. ERW and other promising, high permanence carbon removal methods must complement deep decarbonisation efforts.

Project

Ecologi is currently supporting UNDO’s Canadian projects, focusing on engaging with farming communities to remove megatonnes of carbon alongside socio-economic benefits. The project partners with Canadian Wollastonite, who specialise in the mining and crushing of the fast-weathering mineral, wollastonite. 

Enhanced Rock Weathering (ERW) accelerates the natural weathering of silicate minerals by applying crushed silicate rocks such as basalt, olivine, and wollastonite to the soil. Wollastonite is a highly effective mineral for ERW as a carbon capture method. It absorbs CO₂ much faster than other silicate rocks, requires less material per ton of CO₂ stored, and can be reapplied to land annually. 

Wollastonite has a wealth of co-benefits for farmers and their land. When the rock weathers, it releases calcium, magnesium, and silicon, as well as other major and minor nutrients, into the soil. This results in higher crop yields, increased pest resistance, and improvement in pH of soils. The crushed rock can be spread on any type of cropland and reduces the need for CO2-emitting lime inputs in fields.