CO2 removal should be limited to safe and sustainable measures | Umweltbundesamt

Limiting global warming to 1.5°C will only be possible if human induced CO₂ emissions are reduced to net-zero by around 2050 – in particular by phasing out fossil energy sources, such as coal and oil.  

CO₂ removal measures can by no means replace decarbonisation, yet they are a necessary supplement. Well suited for this are sustainable land use measures, such as soil carbon sequestration in agricultural soils, protection and restoration of wetlands and grasslands as well as reforestation. Such measures can remove CO₂ in an ecologically, socially and economically sustainable manner. UBA therefore supports sustainable land use measures as an approach to Carbon Dioxide Removal and sees an urgent need to create appropriate framework conditions, e.g. provision of financial support, technology transfer and capacity building by developed countries.

However UBA considers it risky to rely on partly unexplored and untested CO₂ removal and storage technologies. Current state of knowledge suggests most CDR technologies encompass potential risks for sustainable development and the environment. For example, Ocean Fertilization, intended to enhance CO₂-sequestration in algae, could over-fertilize and damage marine ecosystems. A further approach is Bioenergy Carbon Capture and Storage (BECCS), relying on industrial style plantations to provide biomass for energetic use and capturing and storing the resulting CO₂ emissions from the burning process. The large scale implementation of BECCS increases competition with food production and other land uses, due to the required large areas of biomass production. It also can have negative impacts on ecosystems, water supply as well as soil and water quality. Depending on the site selection, storage of CO₂ can also pose risks, such as acidification of ground water or generating local seismic activity. 

Further information can be found in the “UBA Position on Carbon Dioxide Removal”.