A 125-year record of climate and chemistry variability at the Pine Island Glacier ice divide, Antarctica

摘要

pstrongAbstract./strong The Mount Johns (MJ) ice core (79?°55a?2span class="thinspace"/spanS; 94?°23a?2span class="thinspace"/spanW) was drilled near the Pine Island Glacier ice divide on the West Antarctic Ice Sheet during the 2008a??2009 austral summer, to a depth of 92.26span class="thinspace"/spanm. The upper 45span class="thinspace"/spanm of the record covers approximately 125??years (1883a??2008), showing marked seasonal variability. Trace element concentrations in 2137 samples were determined using inductively coupled plasma mass spectrometry. In this study, we reconstruct mineral dust and sea salt aerosol transport and investigate the influence of climate variables on the elemental concentrations at the MJ site. The ice core record reflects changes in emissions as well as atmospheric circulation and transport processes. Our trajectory analysis shows distinct seasonality, with strong westerly transport in the winter months and secondary northeasterly transport in the summer. During summer months, the trajectories present slow-moving (short) transport and are more locally influenced than in other seasons. Finally, our reanalysis correlations with trace element suggest that marine-derived trace element concentrations are strongly influenced by sea ice concentration and sea surface temperature anomalies. The results show that seasonal elemental concentration maxima in sea salt elements correlate well with the sea ice concentration winter maxima in the west Amundsen and Ross seas. Lastly, we observed an increased concentration of marine aerosols when sea surface temperature decreased./p.