 |
| Titel |
Constraints on the applicability of the organic temperature proxies UK'37, TEX86 and LDI in the subpolar region around Iceland |
| VerfasserIn |
M. Rodrigo-Gámiz, S. W. Rampen, H. de Haas, M. Baas, S. Schouten, J. S. Sinninghe Damsté |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1726-4170
|
| Digitales Dokument |
URL |
| Erschienen |
In: Biogeosciences ; 12, no. 22 ; Nr. 12, no. 22 (2015-11-19), S.6573-6590 |
| Datensatznummer |
250118168
|
| Publikation (Nr.) |
 copernicus.org/bg-12-6573-2015.pdf |
|
|
|
|
|
| Zusammenfassung |
| Subpolar regions are key areas for studying natural climate variability due to
their high sensitivity to rapid environmental changes, particularly through
sea surface temperature (SST) variations. Here, we have tested three
independent organic temperature proxies (UK'37; TEX86;
and the long-chain diol index, LDI) regarding their potential applicability for SST reconstruction in the subpolar
region around Iceland. UK'37, TEX86 and
TEXL86 temperature estimates from suspended particulate matter
showed a substantial discrepancy with instrumental data, while long-chain
alkyl diols were below the detection limit at most of the stations. In the
northern Iceland Basin, sedimenting particles revealed a seasonality in lipid
fluxes, i.e., high fluxes of alkenones and glycerol dialkyl
glycerol tetraethers (GDGTs) were measured during late
spring and during summer and high fluxes of long-chain alkyl diols during late summer.
The flux-weighted average temperature estimates had a significant negative
(ca. 2.3 °C for UK'37) and positive (up to
5 °C for TEX86) offset with satellite-derived SSTs and
temperature estimates derived from the underlying surface sediment.
UK'37 temperature estimates from surface sediments around
Iceland correlate well with summer mean sea surface temperatures, while
TEX86-derived temperatures correspond with both annual and winter mean
0–200 m temperatures, suggesting a subsurface temperature signal. Anomalous
LDI-SST values in surface sediments and low mass flux of 1,13- and
1,15-diols compared to 1,14-diols suggest that Proboscia diatoms
are the major sources of long-chain alkyl diols in this area rather than
eustigmatophyte algae, and therefore the LDI cannot be applied in this
region. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|