Paleorecords inform the limits of Indo-Pacific coral reef survival under accelerating sea-level rise

Predicting future coral reef responses and climate-driven sea-level rise requires robust historical records of reef vertical accretion rates and their ecological drivers. However, comparable empirical data on past reef growth and framework bioconstruction are often spatiotemporally limited, precluding detection of regional patterns and long-term trends. Here, we compile and evaluate standardized Holocene vertical accretion rates and coral community structure data from 288 Indo-Pacific paleo-reef records across 92 sites to examine intrinsic and extrinsic drivers of accretion. Our findings reveal that reef formation and long-term accretion are determined by a complex interplay between sea-level change and eco-geomorphological factors. Maximum vertical accretion rates indicate that many Indo-Pacific reefs do not have the capacity to keep pace with projected rates of sea-level rise, particularly under high-emissions scenario (76% of reef sites). Critical thresholds suggest that reef accretion is very unlikely (>90% probability) to be maintained when relative sea-level rise rate exceeds 5.3 mm yr^-1, a scenario likely to be surpassed within ~35 years. Without substantial reductions in global emissions, many coral reefs face increasing risk of submergence, structural collapse and loss of critical ecosystem services, especially where modern coral communities differ from predominantly competitive Holocene assemblages and are increasingly dominated by weedy taxa.