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| Titel |
Glacier mass balance reconstruction by sublimation induced enrichment of chemical species on Cerro Tapado (Chilean Andes) |
| VerfasserIn |
P. Ginot, C. Kull, U. Schotterer, M. Schwikowski, H. W. Gäggeler |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1814-9324
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| Digitales Dokument |
URL |
| Erschienen |
In: Climate of the Past ; 2, no. 1 ; Nr. 2, no. 1 (2006-05-23), S.21-30 |
| Datensatznummer |
250000385
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| Publikation (Nr.) |
 copernicus.org/cp-2-21-2006.pdf |
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| Zusammenfassung |
| A 36 m long ice core down to bedrock from the Cerro Tapado glacier
(5536 m a.s.l, 30°08' S, 69°55' W) was analyzed to reconstruct past
climatic conditions for Northern Chile. Because of the marked seasonality in
the precipitation (short wet winter and extended dry summer periods) in this
region, major snow ablation and related post-depositional processes occur on
the glacier surface during summer periods. They include predominantly
sublimation and dry deposition. Assuming that, like measured during the
field campaign, the enrichment of chloride was always related to
sublimation, the chemical record along the ice core may be applied to
reconstruct the history of such secondary processes linked to the past
climatic conditions over northern Chile. For the time period 1962–1999, a
mean annual net accumulation of 316 mm water equivalent (weq) and 327 mm weq
loss by sublimation was deduced by this method. This corresponds to an
initial total annual accumulation of 539 mm weq. The annual variability of
the accumulation and sublimation is related with the Southern Oscillation
Index (SOI): higher net-accumulation during El-Niño years and more
sublimation during La Niña years. The deepest part of the ice record
shows a time discontinuity; with an ice body deposited under different
climatic conditions: 290 mm higher precipitation but with reduced seasonal
distribution (+470 mm in winter and –180 mm in summer) and –3°C lower mean
annual temperature. Unfortunately, its age is unknown. The comparison with
regional proxy data however let us conclude that the glacier buildup did
most likely occur after the dry mid-Holocene. |
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