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Title: Identifying Hydro‐Sensitive Coral δ 18 O Records for Improved High‐Resolution Temperature and Salinity Reconstructions
Abstract

Stable oxygen isotopic ratios in corals (δ18Ocoral) are commonly utilized to reconstruct climate variability beyond the limit of instrumental observations. These measurements provide constraints on past seawater temperature, due to the thermodynamics of isotopic fractionation, but also past salinity, as both salinity and seawater δ18O (δ18Osw) are similarly affected by precipitation/evaporation, advection, and other processes. We use historical observations, isotope‐enabled model simulations, and the PAGES Iso2k database to assess the potential of δ18Ocoralto provide information on past salinity. Using ‘‘pseudocorals’’ to represent δ18Ocoralas a function of observed or simulated temperature and salinity/δ18Osw, we find that δ18Oswcontributes up to 89% of δ18Ocoralvariability in the Western Pacific Warm Pool. Although uncertainty in the δ18Osw‐salinity relationship influences the inferred salinity variability, corals from these sites could provide valuable δ18Oswreconstructions. Coordinated in situ monitoring of salinity and δ18Oswis vital for improving estimates of hydroclimatic change.

 
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Award ID(s):
1847791 2102931 1805143 1945479 1931242 1805702 1805141
NSF-PAR ID:
10445958
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
DOI PREFIX: 10.1029
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
49
Issue:
9
ISSN:
0094-8276
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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