SURFACE OCEANOGRAPHIC VARIABILITY DURING THE LAST GLACIAL MAXIMUM AND LATE HOLOCENE IN THE INDONESIAN MARITIME CONTINENT

Daffa Zettira Mazdhania (Bandung Institute of Technology)
Sandy Hardian Susanto Herho (University of California, Riverside)
Iwan Pramesti Anwar (Bandung Institute of Technology)
Marfasran Hendrizan (National Research and Innovation Agency (BRIN))
Siti Nurzannah Kaban (WorldQuant University)
Faruq Khadami (Bandung Institute of Technology)
Rima Rachmayani (Bandung Institute of Technology)
Sri Yudawati Cahyarini (National Research and Innovation Agency (BRIN))

BULLETIN OF THE MARINE GEOLOGY
Vol 41, No 1 (2026)

This study provides a statistical characterization of surface oceanographic variability in the Indonesian Maritime Continent (IMC) during the Last Glacial Maximum (LGM; 23-19 ka) and Late Holocene (LH; 4-0 ka). Using the lgmDA v2.1 paleoclimate data assimilation product, we analyzed sea surface temperature (SST), sea surface salinity (SSS), and seawater δ¹⁸O. Results indicate the LGM was significantly cooler, saltier, and isotopically enriched, with lower spatial heterogeneity compared to the LH. Comprehensive nonparametric testing confirmed these differences reflected fundamental changes in distributional properties, not merely mean-state shifts. The findings suggest a major oceanographic regime shift, likely driven by lower sea levels, a weakened Indonesian Throughflow (ITF), enhanced stratification, and a drier regional climate during the LGM. This work offers a statistical framework for understanding IMC sensitivity to glacial-interglacial forcing.