Climate-related variabilities in the Styx-M ice core record from northern Victoria Land, East Antarctica, during 1979-2014

Abstract

The historical climate variability in East Antarctica inferred from ice cores remains under debate owing to the vastness and complexity of the region. This study evaluates the potential climate variabilities in the Styx-M ice core records (delta 18O, d-excess, and snow accumulation) from northern Victoria Land adjacent to the Ross Sea sector of East Antarctica during 1979-2014. Results show that the primary moisture source in this area is the Pacific Ocean sector. Although the annual mean delta 18O values was limited to directly indicate the temperature changes, a weak relevance between the average delta 18O values and the temperature signal during the austral summer season is detectable. delta 18O, d-excess, and snow accumulation correlate with sea surface temperature and sea ice extent in the Ross Sea sector. A coupled influence of the SAM, ASL, and ENSO climate indices is expected, because the oceanic environment in this region is influenced by them. The pronounced intrusion of oceanic moisture coupled with atmospheric circulation patterns over the Ross Sea region makes the Styx-M ice core a promising record of the local oceanic conditions, with the snow accumulation rate being a direct proxy. Additionally, the analysis of trace elements from 1979 to 1999 revealed the presence of crustal dust sourced from the Transantarctic Mountains, as well as non-crustal sources, both intricately linked with atmospheric transport. These results demonstrate that the contributions of-and variations in-oceanic conditions associated with atmospheric circulation changes are detectable and dominant in the Styx-M ice core. This study serves as a basis for interpreting longer parts of the Styx-M ice core.