Eastern Australia: A possible source of dust in East Antarctica interglacial ice

Revel-Rolland, Marie; Deckker, Patrick De; Delmonte, Barbara; Hesse, Paul; Magee, John; Basile‐Doelsch, Isabelle; Grousset, F.; Bosch, Delphine

doi:10.1016/j.epsl.2006.06.028

Cited by 191 publications

(197 citation statements)

References 60 publications

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“…Isotope analyses (Nd and Sr) of glacial dust from East Antarctic ice cores have identified Patagonia (Argentina) as the main glacial dust source area, with possible additional contributions from South Africa or Australia [6,8]. Recent analyses on East Antarctic ice cores are confirming a Patagonian origin for dust during glacial times [9], while for interglacial periods other source locations, such as Eastern Australia in particular, may have contributed to a more important extent [10].…”

Section: Introductionmentioning

confidence: 85%

Soluble and insoluble lithium dust in the EPICA DomeC ice core—Implications for changes of the East Antarctic dust provenance during the recent glacial–interglacial transition

Siggaard-Andersen¹,

Gabrielli²,

Steffensen³

et al. 2007

Earth and Planetary Science Letters

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Continental dust impurities in Antarctic ice provide information on climate changes in the dust source areas and on past atmospheric circulation. We investigated records of dust species from the last 45 ka in the East Antarctic EPICA DomeC (EDC) ice core with special emphasis on the lithium (Li) content of dust. We obtained two complementary Li-records using a new Ion Chromatography (IC) technique in line with Inductively Coupled Plasma-Sector Field Mass Spectroscopy (ICP-SFMS). Concentrations of soluble Li (Li + ) were obtained using IC, while total concentrations of Li (Li T ) were obtained using ICP-SFMS, providing an ideal opportunity to investigate the soluble and insoluble chemistry of Li in East Antarctic dust over the last glacialinterglacial transition. The records show that changes in the solubility of Li are associated with climatic changes. For the late glacial period and the Antarctic Cold Reversal (ACR) a large fraction, up to 75%, of the Li T content is present as insoluble minerals whereas for the Holocene period it seems that Li is present mainly as soluble salts (Li + ). We compared the concentrations of Li + with the concentrations of Ca 2+ and the mass and size characteristics of the dust, which were obtained using Coulter Counting (CC). Furthermore we compared the concentrations of Li T with the concentrations of Ba T . Our analysis suggests that the changes in solubility of Li along the EDC ice core are related to changes in compositions of the dust minerals. During the late glacial period, changes in the dust composition is characteristic of variations in the strength of the atmospheric circulation, while changes over the last glacial-interglacial transition are indicative of a change in the major dust source areas. The dust characteristics for the glacial and the Holocene periods indicate two different dust types. The glacial dust type partly disappeared after the ACR, while the Holocene dust type appeared significantly after around 16 ka BP and became dominant after the ACR. The relative increase in the Holocene dust type at the glacial-interglacial transition could be due to changed conditions in the potential source area or to changed patterns of atmospheric circulation, resulting in enhanced transport from a source area that was different from the glacial source areas.

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Section: Introductionmentioning

confidence: 85%

Soluble and insoluble lithium dust in the EPICA DomeC ice core—Implications for changes of the East Antarctic dust provenance during the recent glacial–interglacial transition

Siggaard-Andersen¹,

Gabrielli²,

Steffensen³

et al. 2007

Earth and Planetary Science Letters

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“…Holocene dust sizes measured at these sites are all relatively coarse compared to the ∼ 2 µm modal values measured in the Vostok and EPICA Dome C ice cores from central East Antarctica (e.g., Delmonte et al, 2002). According to a range of geochemical and isotopic evidence, the East Antarctic plateau receives dust primarily from Patagonia, located approximately 6000-7000 km away, although other sources, such as Australia, may contribute during interglacial periods (Basile et al, 1997;Delmonte et al, 2004Delmonte et al, , 2008Revel-Rolland et al, 2006;Marino et al, 2008Marino et al, , 2009. Given the particle size similarities between WAIS Divide and other non-plateau sites, it seems plausible that much of Antarctica has a dust size signature that differs from that of central East Antarctica.…”

Section: Grain Size Distribution and Likely Dust Source(s) For West Amentioning

confidence: 99%

Centennial-scale variability of the Southern Hemisphere westerly wind belt in the eastern Pacific over the past two millennia

et al. 2014

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Abstract. We present the first high-resolution (sub-annual) dust particle data set from West Antarctica, developed from the West Antarctic Ice Sheet (WAIS) Divide deep ice core (79.468 • S, 112.086 • W), and use it to reconstruct changes in atmospheric circulation over the past 2400 years. We find a background dust flux of ∼ 4 mg m −2 year −1 and a mode particle size of 5-8 µm diameter. Through comparing the WAIS Divide record with other Antarctic ice core particle records, we observe that coastal and lower-elevation sites have higher dust fluxes and coarser particle size distributions (PSDs) than sites on the East Antarctic plateau, suggesting input from local dust sources at these lower-elevation sites. In order to explore the use of the WAIS Divide dust PSD as a proxy for past atmospheric circulation, we make quantitative comparisons between both mid-latitude zonal wind speed and West Antarctic meridional wind speed and the dust size record, finding significant positive interannual relationships. We find that the dust PSD is related to midlatitude zonal wind speed via cyclonic activity in the Amundsen Sea region. Using our PSD record, and through comparison with spatially distributed climate reconstructions from the Southern Hemisphere (SH) middle and high latitudes, we infer that the SH westerlies occupied a more southerly position from circa 1050 to 1400 CE (Common Era), coinciding with the Medieval Climate Anomaly (MCA). Subsequently, at ca. 1430 CE, the wind belt shifted equatorward, where it remained until the mid-to-late twentieth century. We find covariability between reconstructions of El Niño-Southern Oscillation (ENSO) and the mid-latitude westerly winds in the eastern Pacific, suggesting that centennial-scale circulation changes in this region are strongly influenced by the tropical Pacific. Further, we observe increased coarse particle deposition over the past 50 years, consistent with observations that the SH westerlies have been shifting southward and intensifying in recent decades.

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“…For example, assuming the latent heat release of the heterogeneous freezing signals to be the same as the latent heat release of the homogeneous freezing signal, the heterogeneous freezing signal represents the freezing of fewer larger droplets and the homogeneous freezing signal the freezing of a high number of smaller droplets. Revel-Rolland et al, 2006;Winckler et al, 2008;Li et al, 2008;Genthon, 1992). Nevertheless, the fine (sieved) fraction of the Antarctica sample is not transported dust but from local erosion, because it exhibited a very similar XRD pattern as larger grains or gravels from the same sample that are too large to be transported.…”

Section: Statistical Evaluation Of Emulsion Measurementsmentioning

confidence: 99%

Ice nucleation efficiency of natural dust samples in the immersion mode

et al. 2016

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Abstract. A total of 12 natural surface dust samples, which were surface-collected on four continents, most of them in dust source regions, were investigated with respect to their ice nucleation activity. Dust collection sites were distributed across Africa, South America, the Middle East, and Antarctica. Mineralogical composition has been determined by means of X-ray diffraction. All samples proved to be mixtures of minerals, with major contributions from quartz, calcite, clay minerals, K-feldspars, and (Na, Ca)-feldspars. Reference samples of these minerals were investigated with the same methods as the natural dust samples. Furthermore, Arizona test dust (ATD) was re-evaluated as a benchmark. Immersion freezing of emulsion and bulk samples was investigated by differential scanning calorimetry. For emulsion measurements, water droplets with a size distribution peaking at about 2 µm, containing different amounts of dust between 0.5 and 50 wt % were cooled until all droplets were frozen. These measurements characterize the average freezing behaviour of particles, as they are sensitive to the average active sites present in a dust sample. In addition, bulk measurements were conducted with one single 2 mg droplet consisting of a 5 wt % aqueous suspension of the dusts/minerals. These measurements allow the investigation of the best icenucleating particles/sites available in a dust sample. All natural dusts, except for the Antarctica and ATD samples, froze in a remarkably narrow temperature range with the heterogeneously frozen fraction reaching 10 % between 244 and 250 K, 25 % between 242 and 246 K, and 50 % between 239 and 244 K. Bulk freezing occurred between 255 and 265 K. In contrast to the natural dusts, the reference minerals revealed ice nucleation temperatures with 2-3 times larger scatter. Calcite, dolomite, dolostone, and muscovite can be considered ice nucleation inactive. For microcline samples, a 50 % heterogeneously frozen fraction occurred above 245 K for all tested suspension concentrations, and a microcline mineral showed bulk freezing temperatures even above 270 K. This makes microcline (KAlSi 3 O 8 ) an exceptionally good ice-nucleating mineral, superior to all other analysed K-feldspars, (Na, Ca)-feldspars, and the clay minerals. In summary, the mineralogical composition can explain the observed freezing behaviour of 5 of the investigated 12 natural dust samples, and partly for 6 samples, leaving the freezing efficiency of only 1 sample not easily explained in terms of its mineral reference components. While this suggests that mineralogical composition is a major determinant of ice-nucleating ability, in practice, most natural samples consist of a mixture of minerals, and this mixture seems to lead to remarkably similar ice nucleation abilities, regardless of their exact composition, so that global models, in a first approximation, may represent mineral dust as a single species with respect to ice nucleation activity. However, more sophisticated representations of ice nucleation by mineral dusts...

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Eastern Australia: A possible source of dust in East Antarctica interglacial ice

Cited by 191 publications

References 60 publications

Soluble and insoluble lithium dust in the EPICA DomeC ice core—Implications for changes of the East Antarctic dust provenance during the recent glacial–interglacial transition

Soluble and insoluble lithium dust in the EPICA DomeC ice core—Implications for changes of the East Antarctic dust provenance during the recent glacial–interglacial transition

Centennial-scale variability of the Southern Hemisphere westerly wind belt in the eastern Pacific over the past two millennia

Ice nucleation efficiency of natural dust samples in the immersion mode

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