云南地区大气降水中氢氧同位素特征及水汽来源分析  

On Characteristics of Hydrogen and Oxygen Isotope in Precipitation in Yunnan and Analysis of Moisture Sources

作　　者：胡菡[1] 王建力[1,2] 

机构地区：[1]西南大学地理科学学院,重庆400715 [2]三峡库区生态环境教育部重点实验室

出　　处：《西南师范大学学报（自然科学版）》2015年第5期142-149,共8页Journal of Southwest China Normal University(Natural Science Edition)

基　　金：国家自然科学基金(40971122);重庆市自然科学基金(CSTS;2007BB7346)

摘　　要：国际原子能机构(IAEA)和世界气象组织(WMO)联合建立了全球降水中稳定同位素组成监测网(GNIP),对昆明站降水中稳定同位素组成进行连续的跟踪监测所得出的数据资料,分析了该地区降水中δ18 O与温度、降水量之间的关系,揭示了降水中δ2 H、δ18 O的变化特征,讨论了水汽输送对降水中δ2 H和δ18 O变化的影响.位于西南水汽通道上的昆明站降水中的稳定同位素比率具有显著的季节变化,旱季(11-4月)降水中平均值明显高于雨季(5-10月),显著的降水量效应说明昆明站降水的水汽主要来源于低纬度海洋.与全球大气水线相比,昆明站大气水线的斜率和常数项均较小.结果表明,年内尺度上,昆明站大气降水中δ18 O与降水量、温度之间存在相关关系,即该地区降水中δ18 O的变化具有显著的降水量效应及反温度效应,利用GrADS模拟该地区风矢量场发现,在夏季风期间,降水中较低的δ18 O主要受来自印度洋暖湿水汽输送的影响,在冬季风期间,降水中较高的δ18 O值主要受西风带水汽输送以及当地蒸发水汽的影响.Based on the monitoring data of Kunming Station collected from GNIP which was confounded by IAEA and WMO ,the characteristics of the hydrogen isotope and oxygen isotope and their relationships with temperature and precipitation have been analyzed in order to reveal the moisture sources based on the statistics .First ,the slope and intercept value of LWML are smaller than other regions in consequence of the Yunnan Guizhou Plateau＇s high altitude .The statistics shows that the variations of hydrogen isotope and oxygen isotope are different from summer and winter obviously with higher values in winter （Decem-ber February） and lower in summer （June August） ,which is partially because of different moisture sources .With further study of deuterium excess and other researches ,it is concluded that local evapora-tion accounts for a crucial proportion in the differences of deuterium excess .Then by virtue of GrADS modeling ,the summer and wind vector field respectively were drawn to verify and prove that the summer moisture sources mainly influenced by moisture transportation of Indian Ocean while the winter moisture sources mainly influenced by moisture transportation of westerly zone and local evaporation .

关 键 词：δ2H Δ18O 氢氧同位素 大气降水 水汽来源 云南地区 

分 类 号：P942[天文地球—自然地理学]