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Title: Colpophyllia natans From Tobago, a Novel Paleoclimate Archive for Reconstructing Sea Surface Temperature in the Tropical Atlantic
Abstract

Massive, long‐livedSiderastreaandDiploriacorals are species commonly used for sea surface temperature (SST) reconstructions in the North Atlantic. However, they are rarely found to exceed 200 years in age. Thus, it is imperative to continuously develop alternative taxa for paleoreconstructions.Colpophyllia natans, a highly populous tropical North Atlantic coral, are known to grow large colonies, potentially containing environmental records spanning several hundreds of years. However, its low density and complicated architecture poses a challenge in extracting climate signals from this coral. This study presents the first monthly‐resolved climate calibration ofColpophyllia natansand validates its utility as a new paleoarchive, relative toSiderastrea siderea.Linear regressions of monthly and interannual coral Sr/Ca with instrumental SST reveal robust, significant relationships (p < 0.05), indicating that microsampling along a single thecal wall ofC. natansallowed for robust climate reconstructions. Additionally, both corals capture similar SST variations (t‐test,p ≥ 0.05), which allowed for the generation of a single, composite interspecies SST record that correlates with instrumental SST even more strongly (p < 0.0001) than the individual corals. Mean annual and boreal summer interspecies SST correlate significantly with North Atlantic SST indices (p < 0.05), demonstrating the ability to capture regional, long‐term SST trends in the North Atlantic. Spatial correlation maps of boreal winter interspecies SST to instrumental SST and geopotential height anomalies reveal coherent spatial patterns linked to the North Atlantic Oscillation. Our findings suggest thatColpophyllia natanshas enormous potential as a new paleoclimate archive for reconstructing temporal and spatial SST variability in the tropical Atlantic.

 
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Award ID(s):
1903586
NSF-PAR ID:
10388071
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
DOI PREFIX: 10.1029
Date Published:
Journal Name:
Paleoceanography and Paleoclimatology
Volume:
37
Issue:
12
ISSN:
2572-4517
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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