benthic carbon isotope and SNW-based [CO32−] for Site GC03 since ~30 ka.

Site GC03 is located on the northern South China Sea at 19.8°N, 115.2°E and 1,365 m water depth. The δ13C data were generated from epibenthic foraminifera Cibicidoides wuellerstorfi, using Thermo Scientific MAT 253 mass spectrometer. [CO32−] is determined using an empirical formula that relates the size-normalized weight of Trilobatus sacculifer to Δ[CO32−], then combined with core-top calibration.