Chloride, Nitrate, and Sulfate in the Dye 3 and Camp Century, Greenland Ice Cores
- C.C. Langway Jr.,
- H. Oeschger and
- W. Dansgaard
Published Online: 18 MAR 2013
Copyright 1985 by the American Geophysical Union.
Greenland Ice Core: Geophysics, Geochemistry, and the Environment
How to Cite
Herron, M. M. and Langway, C. C. (2013) Chloride, Nitrate, and Sulfate in the Dye 3 and Camp Century, Greenland Ice Cores, in Greenland Ice Core: Geophysics, Geochemistry, and the Environment (eds C.C. Langway, H. Oeschger and W. Dansgaard), American Geophysical Union, Washington, D. C.. doi: 10.1029/GM033p0077
- Published Online: 18 MAR 2013
- Published Print: 1 JAN 1985
Print ISBN: 9780875900575
Online ISBN: 9781118664155
- Ice sheets—Greenland—Addresses, essays, lectures;
- Greenland Ice Sheet Program
Concentrations of Cl−, NO3 −, and SO4 2− were measured over the entire depth interval of the deep ice cores from Dye 3 and Camp Century. Using a preliminary time scale for the Dye 3 core and the published Camp Century time scale, the chemical profiles reveal dramatic, synchronous changes in precipitation composition over the last 90,000 years. The Holocene-Wisconsin boundary is marked by a sudden increase in concentrations with increasing depth of all constituents. In the Dye 3 core this transition occurs over an interval of less than 50 cm for SO4 2− and NO3 −, and less than 200 cm for Cl− at a depth of 1786 m. Late Wisconsin ice is characterized by lower NO3 − and higher Cl− and SO4 2− concentrations compared to Holocene levels. Long periods of intensive volcanic activity are indicated by sporadic SO4 2− and lesser Cl− peaks from 10,000 to 20,000 BP and 25,000 to 30,000 BP. The background SO2− 4 concentrations in the Dye 3 core indicate that Late Wisconsin snow accumulation rates were as little as 22% of the present rate, assuming a constant SO4 2− flux. A method is outlined whereby the paleoelevations and perhaps the rate of disintegration of unstable ice masses, such as the West Antarctic Ice Sheet, can be obtained from Cl− concentration profiles.