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Title: Western Pacific Warm Pool δ 18 O Response to the El Niño‐Southern Oscillation
Abstract Tropical Pacific seawater and precipitation stable oxygen isotope data aid in understanding modern oceanic and atmospheric interactions, and these data are particularly valuable as they are archived in isotope‐based paleoclimate records. However, the absence of modern seawater isotope time series limits the ability to identify the atmospheric influences on these data, precluding robust paleoclimate interpretations. We present a new 10 year sub‐monthly record of seawater and precipitation stable oxygen isotope values (δ18Oswand δ18Op) from Koror, Palau. Our dataset indicates that temporally, δ18Oswis strongly influenced by local δ18Op.Both monthly δ18Oswand δ18Opare highly correlated with outgoing longwave radiation across the tropical Pacific, reflecting a Walker Circulation imprint on the surface ocean. Changes in the Palau δ18Osw—salinity relationship correspond to NINO3.4 variability, indicating a difference in how these variables record El Niño Southern Oscillation (ENSO) information, but demonstrating the utility of δ18Oswto reconstruct ENSO variability in the western tropical Pacific.  more » « less
Award ID(s):
1847791
PAR ID:
10611369
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
AGU
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
52
Issue:
3
ISSN:
0094-8276
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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