近60年来南黄海沉积物高分辨率敏感粒级对东亚冬季风的响应

• 作 者: 高星华 李广雪 张海啟 Dada Olusegun A 刘世东 陈中亚 李亨健 王琳淼 刘玲
• 机 构: 海底科学与探测技术教育部重点实验室,中国海洋大学海洋地球科学学院,中国地质调查局发展中心,联邦理工大学海洋科学与技术学院,中国科学院海洋研究所,
• 出 处: 海洋地质前沿
• 发表日期: 2016年08期
• 关键词: sensitive grain-size fraction East Asian Monsoon South Yellow Sea mud area high

对南黄海中部泥质区F306柱状样的沉积物进行分析,运用粒径—标准偏差法,得出该孔敏感粒级组分为23.10~65.30μm(5.44Φ~3.94Φ),其粒级的含量15.6%~22.3%,平均粒径38.5~41.4μm(4.70Φ~4.59Φ),证明敏感粒级可以作为东亚冬季风的高分辨率替代指标,进一步阐明了敏感粒级作为东亚冬季风替代指标在更高分辨率上的可行性。根据敏感粒级沉积记录,在1950—1986年期间,将东亚冬季风分为强—弱—强3个阶段,指示了该阶段东亚冬季风存在近10年的周期。1986/1987为近60多年来东亚冬季风由强变弱的转折点,与东亚气候变化具有较好的对应关系,首次在中国东部海域中记录了此逆转事件,认为1986年后沉积物敏感粒级的变粗可能与长江物源变粗、东亚冬季风的减弱以及夏季风增强有关。

The sediment of column F306 in the southern Yellow Sea muddy area was analyzed, and the particle size-standard deviation method was used to obtain the sensitive component of the pore from 23.10 to 65.30μm (5.44Φ to 3.94Φ) (15.6% ~ 22.3%) and average particle size of 38.5 ~ 41.4μm (4.70Φ ~ 4.59Φ). It is proved that the sensitive grain size can be used as a high-resolution alternative indicator of East Asian winter monsoon, further clarifying the sensitive grain size as a proxy for East Asian winter monsoon Feasibility at higher resolutions. Based on the sensitive grain-level sedimentary records, the East Asian winter monsoon was divided into three stages of strong-weak-strong during 1950-1986, indicating that the East Asian winter monsoon had a period of nearly 10 years during this period. 1986/1987 is the turning point where the East Asian winter monsoon changed from strong to weak in nearly 60 years and has a good correspondence with the climate change in East Asia. For the first time, this reversal event was recorded in the eastern China sea area. It is believed that after 1986, the sediment-sensitive grain size May be related to the thickening of the Yangtze River source, the weakening of the East Asian winter monsoon and the increase of the summer monsoon.