The first comprehensive particulate studies were made on the 2164-m core from Byrd Station (Antarctica: drill date, 1968), the 1390-m core from Camp Century (Greenland: drill date, 1966) core and the 905-m core from Dome C (Antarctica: drill date, 1979). All three cores extend beyond 30,000 years B.P., contain the last glacial/interglacial transition identified using their respective δ 18O records, and show a substantial increase in the dustiness of the global atmosphere during the latter part of the Last Glacial Stage (LGS), also called the Wisconsin or the Würm. Increased atmospheric dust and lower atmospheric temperatures (inferred from 18O depletion) have characterized all subsequent ice cores extending into the LGS, e.g. Dye 3 , Devon Island, Vostok, Dunde ice cap as well in the two recent cores from central Greenland (GISP2 and GRIP). The increase in dust, along with more negative δ 18O values, is a primary indicator of LGS ice in cores from both hemispheres. The 220,000 year Vostok history of dust and δ 18O confirms that atmospheric dust was low during the previous interglacial (Eemian) and high during the previous (penultimate) glacial stage (140,000 to 200,000 years B.P.). The dustiness of glacial stage ice reflects a combination of factors including: increased desertification in major source regions (e.g., Chinese deserts, South Africa and Australia), increases wind speed, increased areas of exposed continental shelves, and in some cases, reduced net accumulation. Regardless of the source(s), increased dust deposition and cooler atmospheric temperatures are closely related over glacial/interglacial time scales.
For a summary please see:
Mosley-Thompson, E. and L.G. Thompson. Dust in polar ice sheets. Analusis,22(8), 44-46. Abstract
Thompson, L.G. and E. Mosley-Thompson. Microparticle Concentration Variations Linked with Climatic Change: Evidence from Polar Ice Cores. Science, 212(4496), 812-815. PDF
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