Spatio-temporal variation mechanisms of hydrogen and oxygen isotopes in precipitation in eurasian continent under climate change

Spatio-temporal isotopic variations and the driving forces in precipitation were explored in Eurasian continent. The results showed that delta 18O, d-excess and delta 2H-delta 18O regressions all presented pronounced spatial heterogeneities among different climate zones, with the distance to sea and the latitude identified as main geographic controls. The Mann-Kendall test revealed that significant temperature increases were observed at the majority (18/20) of the sites. However, delta 18O did not universally exhibit the same upward trend (5/20 sites) as temperature although significant positive delta 18O-temperature correlations existed at most (18/20) sites. The combined effects of multiple environmental factors complicated the interpretation of isotopic signals.