Spatial variation of precipitation in eastern China over the past 150 years based on speleothem multi-proxy analysis

Abstract

In recent years, many researchers have studied spatial variation of summer monsoon precipitation pattern in eastern China during the last 50 years by using instrumental data. However, precisely dated high-resolution reconstructed records spanning over more than a hundred years are still sparse. Here, we present a seasonally-resolved speleothem multi-proxy (Mg/Ca, δ18Oc and δ13C) record spanning 1824–2009 CE from E'mei cave, Jiangxi Province, Southeast China. For the last 180 years, the δ13C record shows similar variation to the Mg/Ca record, and both are consistent with local precipitation, but δ18Oc record shows a unique variation different from δ13C and Mg/Ca records. We suggest that both δ13C and Mg/Ca can reflect changes in local precipitation while δ18Oc is mainly influenced by large-scale monsoon circulation on the long-term trend. Comparison of the Mg/Ca record between E'mei and Shihua caves indicates that the variation of summer monsoon precipitation in the lower reaches of the Yangtze River is opposite to that in northern China during the last ∼150 years, consistent with the pattern of the “northern drought and southern flood” in eastern China observed in instrumental data.