Multicriteria decision analysis to predict potential sites for carbon capture and mineral storage: a pre-feasibility study in southeastern Sicily (Italy)

The large-scale deployment of Carbon Capture and Storage (CCS) technologies is considered essential to limit global warming to safe levels. Among storage options, mineral carbonation is regarded as the safest, as it permanently traps CO₂ in stable carbonate minerals. While its feasibility has been already demonstrated, the technology has yet to be scaled up globally, partly due to the lack of a standardised method for identifying suitable mineral storage sites. This study presents a GIS-based multi-criteria decision analysis (MCDA) workflow for selecting sites for Carbon Capture and Mineral Storage (CCMS), using as case study southeastern Sicily, Italy. The method integrates geological, geophysical, and logistical datasets from open-access sources as well as the scientific literature to generate multi-criteria favourability maps. This allowed to identify three favourable areas for CCMS implementation in southeastern Sicily: (1) the Palagonia area, with a conservative theoretical CO₂ storage capacity of 11–111 Mt; (2) Portopalo di Capo Passero area, 20–201 Mt; and (3) the Catania Plain, 2685–26,851 Mt. Compared to Sicily’s annual CO₂ emissions of ∼27.98 Mt/year, the implementation of CCMS at the identified sites could significantly support regional decarbonisation. Beyond site screening, the workflow offers a transferable spatial decision-support tool for selecting mineral storage sites, which could accelerate the global-scale deployment of the CCMS required to mitigate climate change