How much anthropogenic carbon fixation do we need?

Sci Total Environ. 2024 Jan 15:908:168213. doi: 10.1016/j.scitotenv.2023.168213. Epub 2023 Oct 31.

Abstract

Carbon dioxide (CO2) emissions resulting from human activities are the primary driver of global warming. The reduction of emissions is the key solution to limit global warming, although it is likely that some level of anthropogenic CO2 emissions will remain unavoidable. Therefore, it is crucial to determine the amount of carbon fixation necessary to achieve net zero CO2 emissions and the extent of anthropogenic carbon fixation required to meet this target. According to the RCP2.6 scenario, which aligns with the criteria outlined in the Paris Agreement to keep global warming below 1.5 °C, we have calculated that anthropogenic activity must achieve 1.5 gigatons (Gt) of CO2 to reach net zero CO2 emissions by 2050. This figure will significantly increase if emissions are not reduced by 2050. However, estimating the additional anthropogenic fixation required becomes challenging due to potential disruptions to natural fixation. Therefore, we strongly recommend conducting further research on the stability of natural carbon fixation processes to establish meaningful goals for anthropogenic carbon fixation.

Keywords: Carbon emissions; Carbon fixation; Carbon neutrality; Global warming.