To limit global warming to within 2°C above pre-industrial levels, many are putting their hopes on the world’s abundant supply of biomass – materials like wood and wood residues, energy crops, and agricultural remnants – to deploy large-scale bioenergy with carbon capture and storage (BECCS), the use of which is also assumed to increase considerably in the future. The problem with this strategy, however, is that the detrimental effects of climate change on crop yields may reduce the capacity of BECCS and threaten food security, thus creating an unrecognized positive feedback loop on global warming.
In their study, the research group comprising researchers from IIASA, Fudan University in Shanghai, China, and several other institutions around the world, endeavored to quantify the strength of this feedback by taking a closer look at the nexus of climate change, agriculture, bioenergy, and carbon removal technologies. IIASA provided the core model that enabled the study, along with the associated expertise and feedback in designing the study itself.
Using the shared socioeconomic pathways of climate mitigation, the researchers designed a number of scenarios in which the deployment of large-scale mitigation technologies and BECCS starts in different decades, from 2030 to 2100, and further considered technical solutions to food shortages including cropland expansion, nitrogen fertilizer intensification, nitrogen use efficiency enhancement, afforestation, and international food trade. The feedback on future climate change and food shortages caused by reduced BECCS potential was quantified using an Earth System model and as a function of the delayed mitigation.
Read More at: International Institute for Applied Systems Analysis