Variation of δ18O in precipitation and its response to upstream atmospheric convection and rainout: A case study of Changsha station, south-central China
Publication date: 1 April 2019
Source: Science of The Total Environment, Volume 659
Author(s): Hui Zhou, Xinping Zhang, Tianci Yao, Mingquan Hua, Xuejie Wang, Zhiguo Rao, Xinguang He
The results of analyses of the stable isotopes of oxygen in precipitation (δ18Op) are presented for every rainfall event from January 2010 to December 2017 in Changsha, south-central China. Our aims were to elucidate the variations of δ18Op on different timescales and to identify the main meteorological drivers of variations in the oxygen isotopic composition of precipitation. Results showed that there were no statistically significant and consistent negative correlations between δ18Op and local precipitation amount on either daily or monthly timescale; however, changes in δ18Op in Changsha responded sensitively to the variation of precipitation in the key upstream area along air mass trajectories. Year-to-year, the strongest negative lagged correlations (r’) between δ18Op and the preceding average precipitation amount varied from −0.79 to −0.63 (all significant at the 0.001 level) in the warm half-year (from April to September) of 2010–2017. However, in the cold half-year (from October to the following March), corresponding r’ values varied from −0.79 to −0.38 that were all significant at the 0.001 level, except for the year 2012. These findings suggest that the amplitude of the isotopic signal was closely linked with the position and intensity of upstream rainout activity. This was supported by strong relationships between precipitation-weighted mean δ18O (δ18Ow) and average precipitation amount in the key upstream area at the monthly scale; correlation coefficients were − 0.76 and − 0.57 between 2010 and 2017 in the warm half-year and cold half-year, respectively (both significant at the 0.001 level). Results advance our understanding of the temporal variation of the stable oxygen isotopic composition of precipitation, and demonstrate that local isotopic proxy records may be influenced by upstream rainout processes.
Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.
Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.