资源环境科技发展态势分析平台

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 (δ¹⁸O_spel) are a common data source. However, relationships between δ¹⁸O_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” (δ¹⁸O_spel) records worldwide. The modelled δ¹⁸O_spel spatially correlates with modal signatures. However, substantial changes in modal variance only modestly affect individual δ¹⁸O_spel variance. A network of δ¹⁸O_spel records, particularly one that straddles the Pacific, significantly improves the reconstructability of ENSO variance.