Summer monsoons (South Asian monsoon, South China Sea monsoon and Subtropical monsoon) are prominent features of summertime climate over southern China. Dif- ferent monsoons carry different inflow moisture into Chin...Summer monsoons (South Asian monsoon, South China Sea monsoon and Subtropical monsoon) are prominent features of summertime climate over southern China. Dif- ferent monsoons carry different inflow moisture into China and control the temporal and spatial distributions of precipitation. Analyses of meteorological data, particularly wind, tempera- ture and pressure anomalies are traditional methods of characterizing moisture sources and transport patterns. Here, we try to utilize the evidence from stable isotopes signatures to trace summer monsoons over southern China. Based on seven CHNIP (Chinese Network of Iso- topes in Precipitation) observatory stations located in southern China, monthly composite precipitation samples have been collected and analyzed for the composition of δ^18O during July, 2005. The results indicated that the spatial distributions of δ^18O in precipitation could properly portray the moisture sources together with their transport pathways. Moreover, the amount effect, altitude effect, temperature effect and the correlation between δ^18O vs. relative humidity were discussed.展开更多
This paper reveals the temporal and spatial variations of stable isotope in precipitation of the Yarlung Zangbo River Basin based on the variations of δ^18O in precipitation at four stations (Lhaze, Nugesha, Yangcu...This paper reveals the temporal and spatial variations of stable isotope in precipitation of the Yarlung Zangbo River Basin based on the variations of δ^18O in precipitation at four stations (Lhaze, Nugesha, Yangcun and Nuxia) in 2005. The results show that δ^18O of precipitation has distinct seasonal changes in the Yarlung Zangbo River Basin. The higher value of δ^18O occurs in spring prior to monsoon precipitation, and the lower value occurs during monsoon precipitation. From the spatial variations, with the altitude-effect and rainout process during moisture transport along the Yarlung Zangbo River Valley, δ^18O of precipitation is gradually depleted. Thus, δ^18O of precipitation decreases gradually from the downstream to the upstream, and the lapse rate of δ^18O in precipitation is approximately 0.34‰/100m and 0.7%J‰/100km for the two reasons. During monsoon precipitation, spatial variation of δ^18O in precipitation is dominated by the amount effect in the large scale synoptic condition.展开更多
The paper analyzes the relation between δ(18)O and temperature and precipitation in different regions of the world on the basis of the data from the global observational network set by the International Atomic Energy...The paper analyzes the relation between δ(18)O and temperature and precipitation in different regions of the world on the basis of the data from the global observational network set by the International Atomic Energy Agency (I-AEA) and the World Meteorological Organization (WMO). The results show that there is the marked positive correlation between δ(18)O and temperature in the mid-high latitude continent regions, and the marked negative correlation between δ(18)O and precipitation in the mid-low-latitude ocean and coast stations.展开更多
Holoceneδ^18O records from various archives(ice cores,cave stalagmites,and peat sediments)from the Xinjiang region of northwestern China,in arid central Asia(ACA),are all derived ultimately from local precipitationδ...Holoceneδ^18O records from various archives(ice cores,cave stalagmites,and peat sediments)from the Xinjiang region of northwestern China,in arid central Asia(ACA),are all derived ultimately from local precipitationδ^18O(δ^18Op).Nevertheless,they have been proposed as indicators of different climatic parameters,such as wetness and temperature changes.This article summarizes previously reported records of moisture sources for the Xinjiang region and the results of modern observations conducted at an ice core site and a peat site in the Altai Mountains.The findings are used to propose that the overall positive trends in Holoceneδ^18O records from the various archives from the Xinjiang region primarily reflect the Holocene's long-term warming trend.It is concluded that more site-specific modern observations are needed to further elucidate the environmental significance of Holoceneδ^18O records from this region,especially for the separation of different seasonal temperature signals present withinδ^18O records.展开更多
基金National Natural Science Foundation of China, No. 40671034 Foundation of Isotopes in Precipitation of Chinese Ecosystem Research Network The authors would like to acknowledge Synthesis Center of Chinese Ecosystem Research Center and National Meteorological Information Center, China Meteorological Administration for providing the meteorological data. We also thank Yang Jinrong and Yuan Jingjing for sample analysis. At the same time, sincerely appreciation is given to all the observatory field stations for the collection of precipitation samples and a tour of their facilities.
文摘Summer monsoons (South Asian monsoon, South China Sea monsoon and Subtropical monsoon) are prominent features of summertime climate over southern China. Dif- ferent monsoons carry different inflow moisture into China and control the temporal and spatial distributions of precipitation. Analyses of meteorological data, particularly wind, tempera- ture and pressure anomalies are traditional methods of characterizing moisture sources and transport patterns. Here, we try to utilize the evidence from stable isotopes signatures to trace summer monsoons over southern China. Based on seven CHNIP (Chinese Network of Iso- topes in Precipitation) observatory stations located in southern China, monthly composite precipitation samples have been collected and analyzed for the composition of δ^18O during July, 2005. The results indicated that the spatial distributions of δ^18O in precipitation could properly portray the moisture sources together with their transport pathways. Moreover, the amount effect, altitude effect, temperature effect and the correlation between δ^18O vs. relative humidity were discussed.
基金National Natural Science Foundation of China, No.40121101 No.40671043+2 种基金 No.40571039 National Basic Research Program of China, No.2005CB422002 Knowledge Innovation Program of the Chinese Academy of Sciences, No.KZCX3- SW-339
文摘This paper reveals the temporal and spatial variations of stable isotope in precipitation of the Yarlung Zangbo River Basin based on the variations of δ^18O in precipitation at four stations (Lhaze, Nugesha, Yangcun and Nuxia) in 2005. The results show that δ^18O of precipitation has distinct seasonal changes in the Yarlung Zangbo River Basin. The higher value of δ^18O occurs in spring prior to monsoon precipitation, and the lower value occurs during monsoon precipitation. From the spatial variations, with the altitude-effect and rainout process during moisture transport along the Yarlung Zangbo River Valley, δ^18O of precipitation is gradually depleted. Thus, δ^18O of precipitation decreases gradually from the downstream to the upstream, and the lapse rate of δ^18O in precipitation is approximately 0.34‰/100m and 0.7%J‰/100km for the two reasons. During monsoon precipitation, spatial variation of δ^18O in precipitation is dominated by the amount effect in the large scale synoptic condition.
文摘The paper analyzes the relation between δ(18)O and temperature and precipitation in different regions of the world on the basis of the data from the global observational network set by the International Atomic Energy Agency (I-AEA) and the World Meteorological Organization (WMO). The results show that there is the marked positive correlation between δ(18)O and temperature in the mid-high latitude continent regions, and the marked negative correlation between δ(18)O and precipitation in the mid-low-latitude ocean and coast stations.
基金We dedicate this paper to the memory of Prof.ZiChu Xie,who passed away in early 2020.Prof.ZiChu Xie was an inspirational mentor and friend.This work was supported by the National Science Foundation of China(41772373,41372181)the Hunan Provincial Natural Science foundation of China(2018JJ1017)+1 种基金the National Key R&D Program of China(2018YFA0606404)and the Construction Program for First-Class Disciplines(Geography)of Hunan Province,China(5010002).We thank Dr.Jan Bloemendal for improving the English language.
文摘Holoceneδ^18O records from various archives(ice cores,cave stalagmites,and peat sediments)from the Xinjiang region of northwestern China,in arid central Asia(ACA),are all derived ultimately from local precipitationδ^18O(δ^18Op).Nevertheless,they have been proposed as indicators of different climatic parameters,such as wetness and temperature changes.This article summarizes previously reported records of moisture sources for the Xinjiang region and the results of modern observations conducted at an ice core site and a peat site in the Altai Mountains.The findings are used to propose that the overall positive trends in Holoceneδ^18O records from the various archives from the Xinjiang region primarily reflect the Holocene's long-term warming trend.It is concluded that more site-specific modern observations are needed to further elucidate the environmental significance of Holoceneδ^18O records from this region,especially for the separation of different seasonal temperature signals present withinδ^18O records.