Early summer precipitation in the lower Yangtze River basin for AD 1845-2011 based on tree-ring cellulose oxygen isotopes
Early summer precipitation in the lower Yangtze River basin for AD 1845-2011 based on tree-ring cellulose oxygen isotopes
复制标题
基于树木年轮纤维素氧同位素的公元1845-2011年长江下游流域初夏降水
DOI：
10.1007/s00382-018-4212-5
复制
发表时间：
2018
期刊：
影响因子：
4.6
通讯作者：
Guo Zhengtang
中科院分区：
文献类型：
--
作者：
Xu Chenxi;Shi Jiangfeng;Zhao Yesi;Nakatsuka Takeshi;Sano Masaki;Shi Shiyuan;Guo Zhengtang
6 - 8月的降水通常用来反映东亚夏季风（EASM）的变化。然而，由于东亚副热带锋的季节性移动，5 - 6月（MJ）和7 - 8月（MJ）的主要降水模态有所不同。因此，有必要对它们分别进行研究。本文利用树木年轮纤维素δ18O重建了167年的MJ降水时间序列，解释了中国东南部长江下游地区46.9%的变化，将气象数据扩展到100多年前，使降水研究在年代际尺度上成为可能。有5个或更多异常干湿年的年代是1880年代、1890年代和1910年代，而1980年代和2000年代每十年只有一个异常年。MJ降水与海面绝对温度Niño 3.4呈显著负相关，特别是在El Niño-Southern涛动发展阶段，说明El Niño事件期间降水较少。然而，这种关系在整个时期并不是统一的。进一步的分析表明，当太平洋年代际涛动处于正相位时，它更强。
Precipitation from June to August is generally used to reflect the East Asian summer monsoon (EASM) variability. However, the principal modes of the EASM rainfall are different between May–June (MJ) and July–August due to the seasonal march of East Asian subtropical front. Therefore, it is necessary to study them separately. In this study, we reconstruct a 167-year MJ precipitation time series using tree-ring cellulose δ18O that explains 46.9% of the variance in the lower Yangtze River basin, Southeast China, that extends the meteorological data back more than 100 years and makes the precipitation study at decadal scales possible. The decades with 5 or more anomalously dry or wet years are the 1880s, 1890s, and 1910s, and the 1980s and 2000s have only one anomalous year per decade. MJ precipitation shows a significantly negative relationship with absolute Niño 3.4 sea surface temperature, especially during the developing phases of El Niño-Southern Oscillation, indicating that there is less rainfall during El Niño events. However, the relationship is not uniform throughout the period. Further analyses show that it is stronger when the Pacific Decadal Oscillation is in its positive phases.