Journal Article

Redox condition changes in the Ross Sea, Antarctica, since the last glacial maximum

Han, Xibin, Ge, Qian, Wang, Yizhuo, Hong, Yukai, Li, Xiaohu, Zhang, Yi, Lin, Li, Han, Rui, Liu, Yun, Ma, Pengyun

2025

Overview

Research on changes in the redox conditions of bottom waters is essential for understanding deep water circulation, global ocean currents, climate change, and ecosystem health. Through sedimentary geological methods, a deeper understanding of the complex relationships between various environmental changes can be achieved, providing detailed evidence and theoretical support for global climate change research. The Ross Sea in Antarctica plays a key role in the formation of Antarctic bottom water (AABW), and the complex climate changes since the last glacial maximum (LGM) make it particularly significant for study. This research analyzes core ANT32-RB16C from the Ross Sea using geochemical proxies such as major and trace elements, grain size, and redox-sensitive indicators like Mn/Ti, Co/Ti, Mo/Ti, Cd/Ti, U/Th, and Ni/Co molar concentration ratios. Combining this data with a previously established chronological framework, the study explores the evolution of redox conditions in the Ross Sea’s deep waters since the LGM. The results show that the deep waters have remained oxygen-rich since the LGM, with significant changes in four stages. Stage 1 (24.7–15.7 cal ka BP): Strong oxidizing conditions, likely due to enhanced formation of Ross Sea bottom water (RSBW), increasing oxygen levels. Stage 2 (15.7–4.5 cal ka BP): Weakened oxidizing conditions as temperatures rose and ice shelves retreated, increasing primary productivity and depleting oxygen. Stage 3 (4.5–1.5 cal ka BP): Continued decline in oxidizing conditions, possibly linked to high primary productivity and oxygen consumption. Stage 4 (1.5 cal ka BP to present): A rapid recovery of oxidizing conditions, likely driven by temperature drops, increased RSBW formation, and decreased productivity.

• Publisher: Springer Berlin Heidelberg,Springer Nature B.V
• Subject: Antarctic bottom water / Bottom water / Climate and health / Climate change / Climate change research / Climatology / Deep water / Deep water circulation / Earth and Environmental Science / Earth Sciences / Ecology / Engineering Fluid Dynamics / Environmental changes / Environmental Chemistry / Global climate / Grain size / Ice shelves / Land ice / Last Glacial Maximum / Marine & Freshwater Sciences / Marine ecosystems / Ocean currents / Oceanography / Oxidation / Oxygen / Oxygen consumption / Primary production / Productivity / Titanium / Trace elements / Trace elements (nutrients) / Water circulation / Water currents