摘要
利用长江三峡地区丰都水鸣洞石笋(NSM03)230 Th测年数据和碳同位素数据建立了AD1250～1750时段平均分辨率约为1a的石笋碳同位素时间序列.水鸣洞石笋碳同位素记录显示小冰期开始时间大约为AD1300,与已发表的树轮、孢粉等气候记录指示的小冰期开始时间在定年误差范围内一致;该记录同时显示在小冰期内部存在次一级气候波动,最明显的两次气候波动时间分别在15世纪中期和16世纪末,后者对应过去500年间亚洲季风活动最弱时期.对石笋碳同位素序列进行功率谱分析发现,小冰期气候存在98a和3～6a波动周期,分别与太阳活动世纪周期和ENSO周期相吻合,表明太阳活动是小冰期的主要形成机制,而海气耦合作用则直接影响小冰期气候.
We present in this paper a 230Th-dated stalagmite NSM03 carbon stable isotope record from Shuiming Cave of the area of the Three Gorges. With it we accordingly establish an carbon isotope time se- ries of stalagmite from AD1250-1750 with the average resolution about 1 year. The record of Shuiming Cave suggest that the beginning of Little Ice Age was approximately in AD1300, which is coincide with the records of tree ring, pollen and et al. within the limits of dating error. The record of Shuiming Cave also shows that there were some secondary climatic fluctuations in LIA, the most apparently 2 fluctuations were separately happened in the middle of 15 century and the end of 16 century, the latter corresponded with the period of the weakest Asian Monsoon activity in the past 500 years. We use a power spectrum to analyse the carbon isotope sequence, found that there were 98 years＇ and 3~6 years＇ periodic changes in LIA, they are consistent with the Gleissberg cycle and the ENSO cycle, respectively. The results of the analyze indicate that the sun＇s activity is the change mechanism of LIA climate, meanwhile air-sea coupling also plays a direct role in it.
出处
《西南大学学报（自然科学版）》
CAS
CSCD
北大核心
2013年第3期117-123,共7页
Journal of Southwest University(Natural Science Edition)
基金
国家自然科学基金资助项目(41072141
40902053
41272192)
教育部新教师基金资助项目(20090182120006)
重庆市自然科学基金资助项目(CSTC2009BB7107)
中央高校基本科研业务费项目重大资助项目(XDJK2012A003)
西南大学博士基金资助项目(SWUB2007043)
