El Niño Southern Oscillation signal in a new East Antarctic ice core, Mount Brown South

Abstract

Abstract. Paleoclimate archives, such as high-resolution ice core records, provide a means to investigate long-term (multi-centennial) climate variability. Until recently, the Law Dome (Dome Summit South) ice core record remained one of few long-term high-resolution records in East Antarctica. A new ice core drilled in 2017/2018 at Mount Brown South, approximately 1000 km west of Law Dome, provides an additional high-resolution record that will likely span the last millennium in the Indian Ocean sector of East Antarctica. Here, we compare snowfall accumulation rates and sea salt concentrations in the upper portion (~21 m) of the Mount Brown South record, and an updated Law Dome record over the period 1975–2016. Annual sea salt concentrations from the Mount Brown South record preserves a stronger signal for the El Niño-Southern Oscillation (ENSO; in austral winter and spring, r = 0.521, p

Water isotopes, climate variability, and the hydrological cycle: recent advances and new frontiers

“…High resolution ice core data also help elucidate the dynamical conditions that enhance the strength of tropical-polar teleconnections associated with modes of climate variability like ENSO (Patterson et al 2005, Crockart et al 2021. Indeed, many West Antarctic isotope records are broadly correlated with tropical SSTs on multi-year timescales Steig 2008, Okumura et al 2012).…”