Characteristics of hydrogen and oxygen isotopes in precipitation from october to december 2013 in Chongqing and analysis of moisture sources

Based on monitoring data and meteorological elements at School of Geographical Sciences,South-west University of Chongqing,which were collected from October to December 2013, the LMWL of Chongqing is formulated as δD= 8.1 9δ1 8 O+17.39,r=0.97(p<0.001).The influence of short-term weath-er factors accounts for the larger slope and intercept value of the LMWL.The characteristics of the hydrogen isotope and oxygen isotope and their relationships with temperature and precipitation were analyzed to reveal the moisture sources based on the statistics.The statistics shows that the relationships between hydrogen i-sotope and oxygen isotope are not obvious.Further study suggests that the co-existence of summer monsoon and winter monsoon during the transition span from October to December complicated isotope composition in precipitation.Then by virtue of HYSPLIT modeling,the vapor transport trajectories of every precipitation in Beibei of Chongqing during October to December 2013 are drawn.The resalts show that south-west monsoon was weak and the weather was affected mainly by westerlies in this period.The moisture sources of October and November 2013 were mainly from the Sanjiang drainage in the Hengduan Mountains,and there was moisture transport from tropical storm Haiyan in November.Different moisture sources have great influence toδD andδ1 8 O,and the value ofδD andδ1 8 O have good respond to the different source.While moisture source of rain in December 2013 was mainly from local evaporation.