[A-CC33] Ice cores and paleoenvironmental modeling

[ACC33-P08] Evaluating water isotopes as proxies for climate using a Lagrangian moisture tracking model: A 20-year SE2 ice core record from Greenland

*Ryu Uemura¹, Reo Hoshiya¹, Arie Staal², Sumito Matoba³, Iizuka Yoshinori³ (1.Nagoya University, 2.Utrecht University, 3.Hokkaido University)

Keywords:ice core, stable isotope, paleo climate

Oxygen and hydrogen isotope ratios of water in ice cores have been widely used as temperature proxies. However, the long-term correlation between the isotope ratio and temperature at single locations remains debated. Furthermore, quantifying the relationship between moisture source proxies derived from multiple isotope ratios of water (i.e., d-excess and ¹⁷O-excess) and moisture source environments in polar regions remains even more challenging.
Advancements in meteorological reanalysis allow for better estimation of moisture source conditions, supporting calibration of traditional isotope-based proxies under modern climates. This study measured oxygen and hydrogen isotope ratios in the SE-Dome2 ice core from southeastern Greenland, where snowfall is highest in the Greenland Dome site. Using 20 years of record, we analyzed the relationship between isotope proxies (δ¹⁸O, d-excess, ¹⁷O-excess) and environmental factors derived from hydrological reanalysis data (temperature, sea surface temperature, humidity, wind speed, and oceanic source ratios). Findings enhance understanding of the mechanisms of isotope variability in Greenland and provide an evaluation of the isotope proxies in the ice core.