Deployment expectations of multi-gigatonne scale carbon removal could have adverse impacts on Asia’s energy-water-land nexus | Nature Communications

[Michael Hayes]

"Existing studies indicate that future global carbon dioxide (CO2) removal (CDR) efforts could largely be concentrated in Asia. However, there is limited understanding of how individual Asian countries and regions will respond to varying and uncertain scales of future CDR concerning their energy-land-water system. We address this gap by modeling various levels of CDR-reliant pathways under climate change ambitions in Asia. We find that high CDR reliance leads to residual fossil fuel and industry emissions of about 8 Gigatonnes CO2yr−1 (GtCO2yr−1) by 2050, compared to less than 1 GtCO2yr−1 under moderate-to-low CDR reliance. Moreover, expectations of multi-gigatonne CDR could delay the achievement of domestic net zero CO2 emissions for several Asian countries and regions, and lead to higher land allocation and fertilizer demand for bioenergy crop cultivation. Here, we show that Asian countries and regions should prioritize emission reduction strategies while capitalizing on the advantages of carbon removal when it is most viable."

https://www.nature.com/articles/s41467-024-50594-5 

MH] There are no questions about whether or not agriculture can be carried out in reactors, it can be. The Netherlands became the 2nd largest food exporter by shifting to greenhouse operations and extending that 'enclosed' form of agriculture to marine-grade bioreactors does not have serious technical deployment hurdles. 

Assuming that BECCS, Biochar, CDR in general must depend upon typical agricultural methods is questionable. As things heat up, typical agriculture will become much more stressed and there is a need to expand atypical farming methods. From the CDR view, reactor-based agricultural can turn agriculture from a net C emitter to a C negative activity as all outgassing can be captured and converted for further use.

Interestingly, marine-grade reactors can be C sinks itself and they can be made from the products derived from the crops grown in the reactors, the reactors can be largely self-replicating as well as C negative.