中亚高山区云下与地表降水氢氧稳定同位素时空分布特征及其水汽来源分析  

Spatiotemporal distribution and water vapor sources of stable isotopes of hydrogen and oxygen in below-cloud and surface precipitation in alpine region in Central Asia

作　　者：孙从建 周思捷 陈亚宁[2] 陈伟 乔鹏 SUN Congjian;ZHOU Sijie;CHEN Yaning;CHEN Wei;QIAO Peng(School of Geographical Sciences,Shanxi Normal University,Taiyuan 030031,China;Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences,Urumqi 830011,China)

机构地区：[1]山西师范大学地理科学学院,山西太原030031 [2]中国科学院新疆生态与地理研究所,新疆乌鲁木齐830011

出　　处：《水资源保护》2022年第5期111-121,140,共12页Water Resources Protection

基　　金：国家自然科学基金(41901022);新疆维吾尔自治区区域协同创新专项(上海合作组织科技伙伴计划及国际科技合作计划)(2019E01005);新疆维吾尔自治区创新环境建设专项-天山青年计划(2019Q038)。

摘　　要：基于中亚高山区7个站点的降水稳定同位素观测数据,利用Stewart雨滴蒸发模型及HYSPLIT模型,分析了云下与地表降水稳定同位素的时空分布特征及其与气象因子、地理环境和水汽来源之间的关系。结果表明:研究区地表与云下降水的δ^(2)H和δ^(18)O均表现出明显的季节波动,春夏富集,秋冬贫化;氘盈余则呈现相反的季节变化趋势;云下大气降水线斜率和截距均大于地表大气降水线,说明地表大气降水线受蒸发影响更显著;云下与地表降水的δ^(2)H、δ^(18)O和高程呈显著的负相关关系,而地表氘盈余呈现反高程效应;云下与地表降水δ^(18)O与温度呈正相关关系,氘盈余与温度呈负相关关系,而降水量效应在云下与地表降水中均不显著;水汽输送轨迹显示,夏半年水汽主要源自西伯利亚大陆气团及局地再蒸发水汽,冬半年水汽主要源自西风带输送的北大西洋水汽,且在西风控制下的氘盈余值显著偏高。Based on the observation data of stable isotopes in precipitation at seven stations in the alpine region in Central Asia,this paper uses the Stewart raindrop evaporation model and the hybrid single-particle Lagrangian integrated trajectory(HYSPLIT)model to analyze the spatiotemporal distribution characteristics of stable isotopes in below-cloud and surface precipitation,and their relationships with meteorological factors,the geographical environment,and water vapor sources.The results show that δ^(2)H and δ^(18)O in below-cloud and surface precipitation in the study area show significant seasonal fluctuations:enrich in spring and summer,and deficient in autumn and winter.The deuterium excess(d-excess)shows an opposite seasonal variation trend.The slope and intercept of the below-cloud atmospheric precipitation line are larger than those of the surface precipitation line,indicating that the surface precipitation line is more significantly affected by evaporation.There is a significant negative correlation of δ^(2)H and δ^(18)O in the below-cloud and surface precipitation with elevation,while surface d-excess shows an inverse elevation effect.δ^(18)O in the below-cloud and surface precipitation are positively correlated with temperature,and d-excess is negatively correlated with temperature,while the precipitation effect is not significant in below-cloud and surface precipitation.The water vapor transport trajectory shows that the water vapor in the summer half year mainly comes from the Siberian continental air mass and local re-evaporation water vapor,and the water vapor in the winter half year mainly comes from the North Atlantic water vapor transported by the westerly belt,and the d-excess value is significantly higher under the control of the westerlies.

关 键 词：氢氧稳定同位素 降水线 水汽来源 雨滴蒸发模型 后向轨迹追踪模型 中亚高山区 

分 类 号：P426[天文地球—大气科学及气象学]