摘要
Modeling the oxygen-18 in precipitation based on regional topography and meteorological factors is helpful to constrain missing isotopic data in some regions that is required for many paleoclimate,eco-hydrological and atmospheric circulation studies.Therefore,the relationship betweenδ18Oin precipitation(δ18OPPT)and the affecting factors need to be thoroughly understood.We present a model considering the combined effects of temperature,altitude,and latitude on the spatial variability of annual average of stable isotopes in precipitation across China.This new model performed significantly better(P<0.05)than the widely used Farquhar and Bowen&Wilkinsonmodels.Our model allows modelling the spatial distribution of isotopes in precipitation depending on temperature variation.The residuals of presented model did not significantly correlate with altitude.Based on the model and residuals,a high-resolution map of annual averageδ18Opptacross China was generated.δ18OPPTdecreased from low toward high latitudes and from low towards high altitudes area.The model application provides important information forancient climate,hydrological cycle and water vapor sources studies.
Modeling the oxygen-18 in precipitation based on regional topography and meteorological factors is helpful to constrain missing isotopic data in some regions that is required for many paleoclimate,eco-hydrological and atmospheric circulation studies.Therefore, the relationship between δ18O in precipitation(δ18OPPT) and the affecting factors need to be thoroughly understood. We present a model considering the combined effects of temperature,altitude, and latitude on the spatial variability of annual average of stable isotopes in precipitation across China. This new model performed significantly better（P<0.05） than the widely used Farquhar and Bowen & Wilkinson models. Our model allows modelling the spatial distribution of isotopes in precipitation depending on temperature variation.The residuals of presented model did not significantly correlate with altitude. Based on the model and residuals, a high-resolution map of annual average δ18Oppt across China was generated. δ18OPPT decreased from low toward high latitudes and from low towardshigh altitudes area. The model application provides important information for ancient climate,hydrological cycle and water vapor sources studies.
基金
financially supported by National Natural Science Foundation of China(41790431 and 41471188)
the Innovative Talents Promotion Plan in Shaanxi Province(2017-KJXX-74)
the CAS “Light of West China” Program
