年际-年代际尺度中国地区降水中稳定氧同位素记录的气候学意义

Water stable isotope d18O, as a climate proxy, is the key to investigate paleo- and modern climate changes. However, its climatic implication in China is unclear and remain controversial, partly due to its mid-latitude position where East Asian monsoon always disturbs the isotopic temperature/amount effects (TE/AE). Currently, more observed d18O data and more powerful modeling technique provide the possibility to re-investigate the interannual-to-interdecadal variability of Chinese d18O in precipitation and its climatic implication. This project, by using isotope-enabled climate model and performing model-data comparison, is aiming: 1) to understand Chinese d18O record's climatic implication, in terms of it's links to TE, AE, and atmospheric circulation; and 2) to test the impact of two distinct climate change modes, polar amplification and tropical warming, on the variability of Chinese hydrological cycle and associated d18O footprint; and 3) as the product of this project, to release a centennial-length large-scale ensemble AMIP-type d18O simulation results to serve the climate community. The project will improve our understandings, and provide us more insights in the fundamental dynamics and physics of the isotope-inferred climate change.

在现代气候和古气候研究中，降水中稳定同位素d18O记录是最为核心的气候代用指标。但中国地处中纬度季风区，d18O的气候学意义很不明确，争议很大。随着观测资料的逐渐累积和数值模拟技术的成熟，对现代气候条件下中国地区降水d18O记录的气候学意义适宜进行深入的动力学研究。本项目利用先进的气候模式直接模拟降水d18O和对应的大气环流，并与近50年来中国地区的降水d18O记录进行“模式-观测数据对比”研究（Model-Data Comparison），目标是：1）理解现代气候条件下中国地区年际-年代际d18O记录准确的气候学意义，特别是与温度效应、雨量效应、和大气环流 三者之间的定量关系及背后的物理过程；2）理解当前两种典型气候变化过程（极地增暖型与热带增暖型）对中国地区水循环过程和d18O 变率的影响；3）作为产出，释放一套百年尺度大规模Ensemble AMIP-type同位素模拟数据集。

在现代气候和古气候研究中，降水中稳定同位素d18O记录是重要的气候代用指标。但中国地处中纬度季风区，d18O的气候学意义争议很大。本项目利用先进的气候模式直接模拟降水d18O和对应的大气环流，并与近50年来中国地区的降水d18O记录进行“模式-观测数据对比”研究（Model-Data Comparison），对现代气候条件下中国地区降水d18O记录的气候学意义进行了深入研究。取得成果包括：1）理解现代气候条件下中国地区年际-年代际d18O记录准确的气候学意义，特别是与常规气候要素、亚洲季风、沙尘过程、和Hadley环流之间的关系及背后的物理过程；2）理解北极放大（北极快速增暖）对中国地区气候变化的影响；3）释放一套百年尺度Ensemble AMIPtype同位素模拟数据集。