Overview

• Researchers screened global sedimentary basins for seismic hazards, groundwater risks, biodiversity protections, proximity to populations, engineering depth limits and political feasibility, cutting theoretical capacity from about 11,780 GtCO2 to 1,460 GtCO2.
• Roughly 70% of the prudent capacity lies onshore and 30% offshore, underscoring that earlier, higher totals relied on areas the study deems too risky or impractical for planning purposes.
• Current deployment is tiny by comparison, with about 0.05 GtCO2 stored annually from point‑source capture and roughly 0.00001 GtCO2 from direct air capture.
• Storage potential is uneven, with large capacities in major fossil‑fuel producers such as the US, Australia, Russia and Saudi Arabia, while some European countries have limited options and nations like Brazil and the DRC hold substantial capacity with little domestic incentive to use it.
• Experts diverge on interpretation, with Sally Benson and Jennifer Wilcox calling the estimate conservative relative to near‑term needs, while Naomi Oreskes cautions that governance and economic barriers could shrink practical capacity further; the authors urge treating storage as finite and prioritizing deep emissions cuts.