|
Titel |
Variations in snow and firn chemistry along US ITASE traverses and the effect of surface glazing |
VerfasserIn |
D. A. Dixon, P. A. Mayewski, E. Korotkikh, S. B. Sneed, M. J. Handley, D. S. Introne, T. A. Scambos |
Medientyp |
Artikel
|
Sprache |
Englisch
|
ISSN |
1994-0416
|
Digitales Dokument |
URL |
Erschienen |
In: The Cryosphere ; 7, no. 2 ; Nr. 7, no. 2 (2013-03-26), S.515-535 |
Datensatznummer |
250017948
|
Publikation (Nr.) |
copernicus.org/tc-7-515-2013.pdf |
|
|
|
Zusammenfassung |
This study provides a baseline from which changes in the chemistry of the
atmosphere over Antarctica can be monitored under expected warming scenarios
and continued intensification of industrial activities in the Southern
Hemisphere. It is the first study to measure more than 25 chemical
constituents in the surface snow and firn across extensive regions of
Antarctica. We present major ion, trace element, heavy metal, rare earth
element and oxygen isotope data from a series of surface snow samples and
shallow firn sections collected along four US ITASE traverses across East
and West Antarctica. In each sample we measure dissolved concentrations of
Na+, K+, Mg2+, Ca2+, Cl−, NO3+,
SO42−, and MS− using ion chromatography and total
concentrations of Sr, Cd, Cs, Ba, La, Ce, Pr, Pb, Bi, U, As, Al, S, Ca, Ti,
V, Cr, Mn, Fe, Co, Na, Mg, Li, and K using inductively coupled plasma sector
field mass spectrometry (ICP-SFMS). We also measure δ18O by isotope ratio
mass spectrometry.
Satellite remote sensing measurements of microwave backscatter and grain
size are used to assist in the identification of glaze/dune areas across
Antarctica and determine if these areas can possibly contain useful chemical
climate records. The majority of the non-glaze/dune samples in this study
exhibit similar, or lower, concentrations to those from previous studies.
Consequently, the results presented here comprise a conservative baseline
for Antarctic surface snow chemical concentrations.
The elements Cd, Pb, As and Bi are enriched across Antarctica relative to
both ocean and upper crust elemental ratios. Local and global volcanic
outgassing may account for the majority of the Bi measured in East and West
Antarctica and for a significant fraction of the Cd and As. However,
significant concentrations of Cd, Pb, and As remain across much of
Antarctica. |
|
|
Teil von |
|
|
|
|
|
|