首页|Influence of Sub-Cloud Secondary Evaporation Effects on the Stable Isotopes in Precipitation of Urumqi Glacier No.1,Eastern Tianshan

Influence of Sub-Cloud Secondary Evaporation Effects on the Stable Isotopes in Precipitation of Urumqi Glacier No.1,Eastern Tianshan

扫码查看
原文链接
  • NETL
  • NSTL
  • 万方数据
In arid regions, the stable hydrogen and oxygen isotopic composition in raindrops is often modified by sub-cloud secondary evaporation when they descend from cloud base to ground through the unsaturated air. As a result of kinetic fractionation, the slope and intercept of the δ2H-δ18O correlation equation decrease. The variation of deuterium excess from cloud base to the ground is often used to quantitatively evaluate the influence of secondary evaporation effect on isotopes in precipitation. Based on the event-based precipitation samples collected at Urumqi Glacier No. 1, eastern Tianshan during four-year observation, the existence and impact of secondary evaporation effects were analyzed by the methods of isotope-evaporation model. Under high air temperature, small raindrop diameter and precipitation amount, and low relative humidity conditions, the remaining rate of raindrops is small and the change of deuterium excess is large relatively, and the slope and intercept of δ2H-δ18O cor-relation equation are much lower than those of Global Meteoric Water Line, which mean that the influence secondary evaporation on precipitation enhanced. While on the conditions of low air temperature, high relative humidity, heavy rainfall, and large raindrop diameter, the change of deuterium excess is small relatively and the remaining rate of raindrops is large, and the slope and intercept of δ2H-δ18O correlation equation increase, the secondary evaporation is weakened. The isotope-evaporation model described a good linear correlation between changes of deuterium excess and evaporation proportion with the slope of 0.90‰/％, which indicated that an increase of 1％ in evaporation may result in a decrease of deuterium excess about 0.90‰.

stable isotopesmeteoric water linedeuterium excesssub-cloud secondary evaporation effectprecipitationglaciers

Mengyuan Song、Zhongqin Li、Feiteng Wang、Xin Zhang

展开 >

State Key Laboratory of Cryospheric Sciences,Northwest Institute of Eco-Environment and Resources,Tianshan Glaciological Station,Chinese Academy of Sciences,Lanzhou 730000,China

College of Geography and Environmental Science,Northwest Normal University,Lanzhou 730000,China

College of Sciences,Shihezi University,Shihezi 832000,China

Second Tibetan Plateau Scientific Expedition and ResearchStrategic Priority Research Program of Chinese Academy of Sciences(Class A)Strategic Priority Research Program of Chinese Academy of Sciences(Class A)National Natural Science Foundation of ChinaNational Natural Science Foundation of ChinaSKLCS founding

2019QZKK0201XDA20060201XDA200201024176113409341471058SKLCS-ZZ-2020

2024

10.1007/s12583-021-1522-z

地球科学学刊(英文版)
中国地质大学

地球科学学刊(英文版)

CSTPCD
影响因子：0.724
ISSN：1674-487X
年,卷(期)：2024.35(1)
  • 55