Format:
v, 18 Seiten
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Series Statement:
Research report / Cold Regions Research and Engineering Laboratory, CRREL, US Army Material Command 341
Content:
CONTENTS: Abstract. - Preface. - Introduction. - Samples. - Collection. - Preparation. - Analytical methods. - Cations. - Lead, silicon and aluminum. - Sulfate. - Comparative analyses. - Results and discussion. - Sea salt and terrestrial dust. - Sulfate. - Lead. - Summary and conclusions. - Literature cited. - Appendix A. Concentrations of chemical constituents in Dye 3 snow and ice strata.
Content:
Concentrations of sodium, potassium, magnesium, calcium, silicon, aluminum, lead and sulfate were measured in surface snow and in individual annual accumulation layers from a 373-m-deep ice core from Dye 3, Greenland, covering the time period from 1232 to 1971 A.D. Average background (pre-1840) concentrations in micrograms/liter are: Na, 12.9 ± 9.3; K, 2.2 ± 2.1; Mg, 1.5 ± 1.0; Ca, 4.8 ± 2.4; Si, 12 ± 6; Al, 3.3 ± 1.4; Pb, 0.07 ± 0.06; and SO4, 56 ± 22. Deviations are due mainly to the variability of the concentrations in the samples deposited over the stated time interval rather than analytical precision. Observed concentrations of sodium, potassium, magnesium, calcium, silicon and aluminum can be adequately explained by relative abundances of these elements in seawater andterrestrial dust. Late 19th century annual ice layers contain twice as much sulfate as pre-1840 deposits, reflecting the increased use of fossil fuels in the Northern Hemisphere. Lead concentrations in post-1955 snow deposits are more than an order of magnitude greater than pre-1840 baseline concentrations and are attributed to smelting and the increased use of lead alkyls in gasoline.
Note:
MAB0014.001: ZSP-202-341
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Online frei verfügbar
In:
Research report
Language:
English
Keywords:
Forschungsbericht
URL:
https://babel.hathitrust.org/cgi/pt?id=uc1.31210025592088&seq=1
