Modern climatic signals deduced from stable isotope in shells in Xingcuo Lake sediments, east Tibetan Plateau, China

Abstract

Xingcuo lake, a closed one, is situated in eastern Tibetan Plateau. There are abundant snail shells Gyraulus sibirica in its sediments. Here we display the determining results of δ13C, δ18O in shell Gyraulus sibirica continuously preserved in Xincuo Lake sediments in the recent 50 years. And by coupling the indexes of δ13C, δ18O and instrumental meteorological data in its basin to build relative function relations among them, we probe quantitatively climatic signals recorded in those indexes. The results show that there are remarkable relations between δ13C proxy and precipitation, δ18O proxy and air temperature, of which correlative coefficient was 0.89 and 0.71, respectively. Besides, we also demonstrated that average variation between δ13C proxy and precipitation (dδ13C/dP) was 0.027‰/mm and 1.64‰/°C for δ18O and air temperature (dδ18O/dT).