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Title: Oxygen Isotopic Signatures of Major Climate Modes and Implications for Detectability in Speleothems

Natural and social systems worldwide are impacted by climate modes such as the El Niño/Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO) and Atlantic Multidecadal Oscillation (AMO), making it imperative to understand their sensitivity to climate change. Paleoclimate studies extend the observational climate baseline, and speleothem records (δ18Ospel) are a common data source. However, relationships between δ18Ospeland climate modes are uncertain; climate models provide a way to test the strength and stability of these relationships. Here, we use the isotope‐enabled Community Earth System Model's Last Millennium Ensemble combined with a forward proxy model to delineate the global expression of modal variability in “pseudo‐stalagmite” (δ18Ospel) records worldwide. The modeled δ18Ospelspatially correlates with modal signatures. However, substantial changes in modal variance only modestly affect individual δ18Ospelvariance. A network of δ18Ospelrecords, particularly one that straddles the Pacific, significantly improves the reconstructability of ENSO variance.

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Award ID(s):
1805143 1702271
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
DOI PREFIX: 10.1029
Date Published:
Journal Name:
Geophysical Research Letters
Medium: X
Sponsoring Org:
National Science Foundation
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