Premium
Oxygen Isotopic Signatures of Major Climate Modes and Implications for Detectability in Speleothems
Author(s) -
Midhun M.,
Stevenson S.,
Cole J. E.
Publication year - 2021
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2020gl089515
Subject(s) - stalagmite , speleothem , climatology , paleoclimatology , proxy (statistics) , climate model , pacific decadal oscillation , climate sensitivity , climate change , geology , environmental science , el niño southern oscillation , oceanography , geography , holocene , cave , archaeology , machine learning , computer science
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 (δ 18 O spel ) are a common data source. However, relationships between δ 18 O spel and 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” (δ 18 O spel ) records worldwide. The modeled δ 18 O spel spatially correlates with modal signatures. However, substantial changes in modal variance only modestly affect individual δ 18 O spel variance. A network of δ 18 O spel records, particularly one that straddles the Pacific, significantly improves the reconstructability of ENSO variance.