Dataset for Indian Ocean Salinity build-up primes Deglacial Ocean Circulation Recovery@en

This dataset explores the variability in glacial-interglacial surface hydrography in the western Indian Ocean across the middle to late Pleistocene. Here, we provide 1kyr resolution Mg/Ca-based sea surface temperatures and surface oxygen isotope ratios of seawater (ice volume corrected) as proxy for surface palaeo-salinity from surface dwelling foraminifera Globigerinoides ruber from International Ocean Discovery Program core site U1476 located in the Mozambique Channel, which we use in combination with other records to create Indian Ocean sea surface salinity and sea surface temperature stacks. The data show increases in sea surface temperature and salinity during glaciation, with maximum temperature and salinity occurring at glacial maxima, prior to global deglaciations as indicated by benthic oxygen isotopes, a proxy for global ice volume. Lead-lag analyses were conducted using cross-spectral analysis between sea surface temperatures, salinity, and benthic oxygen isotopes. In parallel, sea-to-land pixel ratios from the ANICE-SELEN model across the Indonesian Archipelago show changes in land surfacing in the Indonesian archipelago due to globally sinking sea levels. The increase in surface temperature and salinification at U1476 occurs at the same time as major land surfacing in the Indonesian Archipelago suggesting a mechanistical link between land surfacing due to global sea level lowering, and changes in Indian Ocean surface hydrography that appears to be a resulting reduction in the considerably fresher Indonesian throughflow entering the Indian Ocean.本数据集探究了更新世中晚期印度洋西部冰期-间冰期表层水文的变化特征。本研究提供了采自莫桑比克海峡国际大洋发现计划（International Ocean Discovery Program）岩心站点U1476处，表层浮游有孔虫红拟抱球虫（Globigerinoides ruber）的、基于镁钙比（Mg/Ca）的千年分辨率海表温度数据，以及经冰体积校正的海水表层氧同位素比值数据——后者作为古表层盐度的代用指标。我们将上述数据与其他记录相结合，构建了印度洋海表盐度与海表温度堆叠序列。数据显示，冰期阶段海表温度与盐度均呈升高趋势，最高温与最高盐度出现在冰盛期（glacial maxima），且早于代表全球冰体积的底栖氧同位素指标所指示的全球冰消期。研究通过海表温度、盐度与底栖氧同位素间的交叉谱分析（cross-spectral analysis）开展了时滞分析（Lead-lag analyses）。与此同时，基于ANICE-SELEN模型得到的印度尼西亚群岛海-陆像素比数据，揭示了因全球海平面下降导致的该群岛陆地出露变化。U1476站点的海表温度升高与盐化过程，与印度尼西亚群岛的大规模陆地出露发生在同一时期，这表明全球海平面下降引发的陆地出露，与印度洋表层水文变化之间存在机制性关联——该水文变化的诱因似乎是进入印度洋的低盐度印度尼西亚贯穿流（Indonesian throughflow）显著减少。