Open AccessA high‐resolution investigation of temperature, salinity, and upwelling activity proxies in corals
Author(s) -
Ourbak Timothée,
Corrège Thierry,
Malaizé Bruno,
Le Cornec Florence,
Charlier Karine,
Peypouquet Jean Pierre
Publication year - 2006
Publication title -
geochemistry, geophysics, geosystems
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.928
H-Index - 136
ISSN - 1525-2027
DOI - 10.1029/2005gc001064
Subject(s) - upwelling , salinity , geology , sea surface temperature , coral , oceanography , sss* , alkenone , mathematical optimization , mathematics
We present a high‐resolution study of five geochemical components of a New Caledonia coral core. Minor and trace elements (Sr/Ca, U/Ca, Mg/Ca, Ba/Ca), together with oxygen isotopes (δ 18 O), were investigated at near‐fortnightly resolution. Geochemical measurements were compared to sea surface temperature (SST TSG ) and salinity (SSS TSG ) recorded by a thermosalinograph (TSG) located less than 10 m from the coral. Results show that Sr/Ca, Mg/Ca, and δ 18 O are temperature‐dependent (correlation coefficient to local SST TSG between 0.74 and 0.84). Their robustness as SST tracers is tested against a satellite‐based data set for a 4 year validation period. U/Ca has a more complex behavior and appears to be linked to both SST TSG and SSS TSG , despite relatively small local SSS variations. For the first time this salinity‐related imprint is quantified in a U/Ca coralline ratio. In addition to SST and SSS tracers, Ba/Ca measurements provide a possible way to investigate upwelling activity occurrences.