Microfossil Abundances Constrain CaCO3 Dissolution in the Equatorial Pacific at the Last Glacial Maximum and Late Holocene

Datasets for:Radiocarbon ages from cores MW91-09-GGC15, 45, and 29. Radiocarbon dates were converted to calendar age using CALIB8.2 and the MARINE20 calibration curve (Heaton et al., 2020) with a local DR = -102.Planktic foraminifera species assemblage counts and percentages.Planktic foraminifera R/S values calculated from The Brown Foraminiferal Database (Prell et al., 1999) with modern Ωcalcite and Δ[CO₃²⁻] derived from GLODAP v2.2023 database (Lauvset et al., 2021, 2022; Olsen et al., 2019, 2020).CaCO3 mass data on different size fractions (bulk, 63 mm). Also included are mass data from Subhas et al., 2019.Principal components, input variables (assemblage percentages), 230Th-based mass fluxes (Costa et al., 2016), and modern data derived from GLODAP v2.2023 database (Lauvset et al., 2021, 2022; Olsen et al., 2019, 2020).Reconstructed Δ(Δ[CO₃²⁻]) values from this study and independent reconstructions of Δ(Δ[CO₃²⁻]) from the Equatorial Pacific (de la Fuente et al., 2017; Fritz-Endres, Theresa, 2022; Jacobel et al., 2025; Kerr et al., 2017; Umling & Thunell, 2018; Yu et al., 2013). Anomalies, Δ([Δ[CO₃²⁻]), were calculated from averaged reconstructed LGM values minus averaged reconstructed late Holocene values, and their standard deviations reflect propagation of the original point-wise standard deviations when available.Stratigraphy of MW91-09 48GGC and 18GGC (𝛿18O on T. sacculifer) from Thunnell, unpublished.