In this study, we established an annually resolved chronology for the upper 98.5 m of a 210.5 m deep ice core (Styx-M core) drilled at the Styx Glacier plateau (SGP) in northern Victoria Land, East Antarctica, to reconstruct the multi-centennial variations of the snow accumulation rate (SAR). The core was dated via the annual layer counting of highly resolved impurities exhibiting seasonal cycles. The layer counting result was constrained using multiple temporal markers, including the 239Pu peaks that resulted from atmospheric weapon tests as well as five large volcanic eruptions in recorded history. These approaches show that the Styx-M core chronology covered 755 years (1259–2014 CE), with the estimated dating uncertainties of ±8 years. The annual accumulation record was derived using the depth-age scale and depth-density relationships of the core. This record revealed a long-term trend of a ∼30% increase in the SARs over the past 755 years, overlapping the pronounced inter-decadal and multi-decadal fluctuations. Further study will be needed to reveal the complex interaction of oceanic and atmospheric processes controlling the temporal fluctuations of SARs in the coastal areas of northern Victoria Land, combining multiple proxy records in the Styx-M core.

Under the potential to reconstruct the past climatic and atmospheric conditions from a deep ice core in the coastal Antarctic site (Styx Glacier), an 8.84 m long firn core (73°50.975′ S, 163°41.640′ E; 1623 m a.s.l.) was initially studied to propose a reliable age scale for the local estimation of snow accumulation rate. The seasonal variations of δ18O, methanesulfonic acid (MSA) and non-sea-salt sulfate (nssSO42–) were used for the firn core dating and revealed 25 annual peaks (from 1990 to 2014) with volcanic sulfate signal. The observed declining trend in annual accumulation rate with a mean value of 146 ± 60 kg m–2 a–1 is likely to be linked to the changes of sea-ice extent in the Ross Sea region. Moreover, the temporal variation of the annual mean δ18O, an annual flux of MSA and nssSO42– also likely to be under the influence of ice-covered and open water area. This study suggests a potential to recover past changes in an oceanic environment and will be useful for the interpretation of the long ice core drilled at the same site.