Interpretation of eastern Antarctic ice core proxy climate records can be improved through better understanding of the climate dynamics and variability of the Southern Indian Ocean over multiple time scales.   In the case of high-resolution (seasonal to annual) ice cores, this is especially important, as event-scale precipitation and redistribution of the snow at the surface can enhance or weaken links to regional climate processes.  Two high resolution ice cores in East Antarctica, Law Dome and Mt Brown South (MBS) in Wilhelm II Land (drilled in 2017/2018), provide an opportunity to extend and broaden our understanding of Southern Indian Ocean climate dynamics and variability over the last 2000 years.  For example, climate proxies from Law Dome have been found to be correlated with annual rainfall variability in southwest Western Australia and eastern subtropical Australia.  However, poor understanding of the climate dynamics and variability in the mid to high latitude Southern Indian and SW Pacific Oceans across all timescales (synoptic to centennial) hampers the interpretation of these long high-quality climate proxies.  

Here we present results from a synoptic typing study for the Southern Ocean region between 40°E and 180°E – the ‘atmospheric catchment’ region for both Law Dome and MBS.  As a demonstration of how synoptic classification provides a link between large scale atmospheric circulation and local climate parameters, the synoptic types are related to precipitation anomalies in Southern Australia and Eastern Antarctica.  At the ice core sites, synoptic typing enables the examination of important synoptic processes that may lead to the amplification or damping of climate signals preserved in ice core climate proxies.  Improved understanding and interpretation of ice core climate proxies, especially during atypical years, will enhance the application of ice core proxies for understanding, quantifying and managing the impacts of climate variability and change in the Southern Hemisphere.