 |
| Titel |
Stalagmite water content as a proxy for drip water supply in tropical and subtropical areas |
| VerfasserIn |
N. Vogel, Y. Scheidegger, M. S. Brennwald, D. Fleitmann, S. Figura, R. Wieler, R. Kipfer |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1814-9324
|
| Digitales Dokument |
URL |
| Erschienen |
In: Climate of the Past ; 9, no. 1 ; Nr. 9, no. 1 (2013-01-07), S.1-12 |
| Datensatznummer |
250006686
|
| Publikation (Nr.) |
 copernicus.org/cp-9-1-2013.pdf |
|
|
|
|
|
| Zusammenfassung |
| In this pilot study water was extracted from samples of two Holocene
stalagmites from Socotra Island, Yemen, and one Eemian stalagmite from
southern continental Yemen. The amount of water extracted per unit mass of
stalagmite rock, termed "water yield" hereafter, serves as a measure of
its total water content. Based on direct correlation plots of water yields
and δ18Ocalcite and on regime shift analyses, we
demonstrate that for the studied stalagmites the water yield records vary
systematically with the corresponding oxygen isotopic compositions of the
calcite (δ18Ocalcite). Within each stalagmite lower
δ18Ocalcite values are accompanied by lower water yields
and vice versa. The δ18Ocalcite records of the studied
stalagmites have previously been interpreted to predominantly reflect the
amount of rainfall in the area; thus, water yields can be linked to drip
water supply. Higher, and therefore more continuous drip water supply caused
by higher rainfall rates, supports homogeneous deposition of calcite with low
porosity and therefore a small fraction of water-filled inclusions,
resulting in low water yields of the respective samples. A reduction of drip
water supply fosters irregular growth of calcite with higher porosity,
leading to an increase of the fraction of water-filled inclusions and thus
higher water yields. The results are consistent with the literature on
stalagmite growth and supported by optical inspection of thin sections of
our samples. We propose that for a stalagmite from a dry tropical or subtropical
area, its water yield record represents a novel paleo-climate proxy
recording changes in drip water supply, which can in turn be interpreted in
terms of associated rainfall rates. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|