Back to Search
Start Over
Comparison of equatorial Pacific sea surface temperature variability and trends with Sr/Ca records from multiple corals
- Source :
- Paleoceanography. 31:252-265
- Publication Year :
- 2016
- Publisher :
- American Geophysical Union (AGU), 2016.
-
Abstract
- Coral Sr/Ca is widely used to reconstruct past ocean temperatures. However, some studies report different Sr/Ca-temperature relationships for conspecifics on the same reef, with profound implications for interpretation of reconstructed temperatures. We assess whether these differences are attributable to small-scale oceanographic variability or “vital effects” associated with coral calcification and quantify the effect of intercolony differences on temperature estimates and uncertainties. Sr/Ca records from four massive Porites colonies growing on the east and west sides of Jarvis Island, central equatorial Pacific, were compared with in situ logger temperatures spanning 2002–2012. In general, Sr/Ca captured the occurrence of interannual sea surface temperature events but their amplitude was not consistently recorded by any of the corals. No long-term trend was identified in the instrumental data, yet Sr/Ca of one coral implied a statistically significant cooling trend while that of its neighbor implied a warming trend. Slopes of Sr/Ca-temperature regressions from the four different colonies were within error, but offsets in mean Sr/Ca rendered the regressions statistically distinct. Assuming that these relationships represent the full range of Sr/Ca-temperature calibrations in Jarvis Porites, we assessed how well Sr/Ca of a nonliving coral with an unknown Sr/Ca-temperature relationship can constrain past temperatures. Our results indicate that standard error of prediction methods underestimate the actual error as we could not reliably reconstruct the amplitude or frequency of El Nino–Southern Oscillation events as large as ± 2°C. Our results underscore the importance of characterizing the full range of temperature-Sr/Ca relationships at each study site to estimate true error.
- Subjects :
- geography
geography.geographical_feature_category
010504 meteorology & atmospheric sciences
biology
Range (biology)
Coral
Porites
Paleontology
010502 geochemistry & geophysics
Oceanography
biology.organism_classification
01 natural sciences
Sea surface temperature
Paleoceanography
Walker circulation
Reef
Geology
Siderastrea siderea
0105 earth and related environmental sciences
Subjects
Details
- ISSN :
- 19449186 and 08838305
- Volume :
- 31
- Database :
- OpenAIRE
- Journal :
- Paleoceanography
- Accession number :
- edsair.doi...........d05323c52634ff8628cc41eea64db913