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Changes in the composition of dust trapped in ice provide evidence of past atmospheric circulation and earth surface conditions. Investigations of dust provenance in Antarctic ice during glacial and interglacial periods indicate that South America is the primary dust source during both climate regimes. Here, we present results from a new ice core dust archive extracted from the Taylor Glacier in coastal East Antarctica during the deglacial transition from Marine Isotope Stage 6 to 5e. Radiogenic strontium and neodymium isotopes indicate that last interglacial dust is young and volcanic, in contrast to the observed preindustrial and Holocene (Marine Isotope Stage 1) dust composition. The dust composition differences from the last interglacial and current interglacial period at the site require a profound difference in atmospheric transport and environmental conditions. We consider several potential causes for enhanced transport of volcanic material to the site, including increased availability of volcanic material and large‐scale atmospheric circulation changes. Fluctuations in the isotopic composition of dust particles transported atmospherically and trapped in East Antarctic ice during glacial and interglacial periods provide glimpses into past earth surface conditions and atmospheric dynamics through time. Here we present new ice core records of dust from the Taylor Glacier (Antarctica), extending back to the transition into the last interglacial period (~130,000 years ago). Dust deposited at this site during the last interglacial period has a significantly more volcanic dust composition compared to the current interglacial dust, caused by a pronounced wind direction change and/or increased subaerial exposure of volcanic material. The distinct dust compositions during two separate interglacial periods suggest significant differences in conditions at the dust source areas and atmospheric dynamics to this peripheral Antarctic site. Last interglacial dust composition in Taylor Glacier ice is distinct from MIS 1 recordSr and Nd isotope signatures indicate a young volcanic sourceGeochemical data suggest a change in provenance and atmospheric circulation between MIS 5e and MIS 1

During the last decades, ice cores drilled in Antarctica and in Greenland have provided time series of data that have allowed the characterisation of variations of natural and anthropogenic heavy metals in the past atmosphere. Nevertheless, the interactions of heavy metals with climate change and their transport patterns remain largely unknown during the last climatic cycles. Hereafter we present our project dealing with the assessment of past changes of various heavy metals in Antarctic and Greenland ice during the past = 500 kyr anticipating some preliminary Zn measurements in the EPICA Dome C ice core back to about 200000 years. In our project special emphasis is given to Pt group elements (PGE) that are tracers of interplanetary dust particles (IDPs). Tracers of crustal material, volcanic activity and ocean paleoproductivity are also investigated. At the moment we are focusing especially on the ongoing EPICA Dome C Antarctic ice core, decontaminating mechanically some section and perfonning preliminary measurements of Zn and Al using Graphite Fumace Atomic Absorption Spectrometry and adopting ultraclean procedures. These data confinn the prominent continental origin of Zn in the East Antarctic ice during the last and penultimate glacial period.

The geographical origin of the mineral dust transported to the East Antarctic Plateau from the Southern Hemisphere (SH) continents has been investigated by means of the isotopic (Sr-Nd) signature of samples from Potential Source Areas (PSAs). Dust reaching Antarctica is fine-grained (<5 μum), and therefore the new isotopic fields have been defined in the equivalent size range. The so obtained dataset evidences a partial overlap among the signatures of the Ice Cote dust and South America, New Zealand and the Antarctic Dry Valleys, while South Africa appear distinctly different: further data are needed for the Australian continent Despite the geochemical similarity with the Dry Valleys and New Zealand, Southern South America still appears to be the most probable source for dust in Antarctica in glacial times.

Changing climate conditions affect dust emissions and the global dust cycle, which in turn affects climate and biogeochemistry. In this study we use observationally constrained model reconstructions of the global dust cycle since the Last Glacial Maximum, combined with different simplified assumptions of atmospheric and sea ice processing of dust‐borne iron, to provide estimates of soluble iron deposition to the oceans. For different climate conditions, we discuss uncertainties in model‐based estimates of atmospheric processing and dust deposition to key oceanic regions, highlighting the large degree of uncertainty of this important variable for ocean biogeochemistry and the global carbon cycle. We also show the role of sea ice acting as a time buffer and processing agent, which results in a delayed and pulse‐like soluble iron release into the ocean during the melting season, with monthly peaks up to ~17 Gg/month released into the Southern Oceans during the Last Glacial Maximum (LGM). Data‐constrained time‐slice CESM simulations estimate global dust variability since LGMBudgets and uncertainties in dust and soluble iron deposition to key ocean regions for biogeochemical cyclesElevated soluble iron inputs to the Atlantic sector of the Southern Ocean in the LGM