Page 32 - 《高原气象》2025年第6期

高 原 气 象 44 卷
1440

Multi-model Comparison and Evaluation of Precipitation

Oxygen Isotopes over the Qinghai-Xizang Plateau

1， 3
1， 3
2
SHI Yuqing ， HU Jun ， LIU Guangsheng ， CHEN Xu ， NIU Yanyan 1， 3
1， 3
（1. School of Environmental Science and Engineering， Xiamen University of Technology， Xiamen 361024， Fujian， China；
2. College of Ocean and Earth Sciences， Xiamen University， Xiamen 361002， Fujian， China；
3. Xiamen Key Laboratory of Water Resources Utilization and Protection， Xiamen 361024， Fujian， China）
Abstract： The stable isotopes of hydrogen and oxygen in precipitation over the Qinghai-Xizang Plateau and their
related proxy data such as ice cores and tree rings are of great significance for a deeper understanding of the cli‐
mate and hydrological changes on the Qinghai-Xizang Plateau. The introduction of stable water hydrogen and ox‐
ygen isotope modules in atmospheric circulation models helps understand the climatic interpretations of precipita‐
tion isotopes and related paleoclimate proxy data. In recent years， some studies have applied nudging techniques
to these models to reduce model errors by fusing reanalysis data. However， further research is needed to deter‐
mine the extent to which this method improves the simulated precipitation isotopes. This study used data from the
Qinghai-Xizang （Tibetan） Plateau Network Isotope Plan （TNIP） to evaluate four atmospheric models with water
isotope modules and compare the results with and without nudging reanalysis data. The results indicate that all
four models can well reproduce the climate mean annual precipitation δ O and seasonal variability of precipita‐
18
18
tion δ O， while the models have lower simulation ability for interannual variability of precipitation δ O. The
18
simulations of the spatial distribution and seasonal cycle changes of precipitation δ O over the Qinghai-Xizang
18
Plateau with nudging reanalysis data is significantly better than that of free running simulations. The differences
in model choice have a greater impact on the simulation results than the differences in nudged reanalysis data.
Overall， the fusion of reanalysis data can effectively correct the model bias in the atmospheric circulation over
and around the Qinghai-Xizang Plateau， thereby improving the model's ability to simulate precipitation and pre‐
cipitation δ O. This study provides a useful reference for simulating stable isotopes of precipitation over the Qin‐
18
ghai-Xizang Plateau using models and the improvement effect of nudging techniques on the hydrological and cli‐
matic simulation of the Qinghai-Xizang Plateau.
Key words： precipitation isotopes； Qinghai-Xizang Plateau； seasonal cycle； model simulations