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热带海洋表面温度的短暂上升,发生在古世 - 世热量最大时期
James C Zachos1, Michael W Wara, Steven Bohaty
1Earth and Ocean Sciences Departments, University of California, Santa Cruz, CA 95064, USA. jzachos@es.ucsc.edu
概括
古世 - 世热极值造成了显著的海洋变暖,热带太平洋海面温度上升了4-5°C. 这种变暖表明大气中的二氧化碳含量比以前估计的要高.
科学领域:
- 古气候学 古气候学
- 海洋学 海洋学 海洋学
- 地质化学 地质化学
背景情况:
- 古世 - 世热极值 (PETM) 是一个全球快速变暖的时期.
- 所有度都预计会变暖,但热带海面温度 (SST) 的变化不受限制.
- 高度记录显示了显著的SST和底层水的变暖.
研究的目的:
- 在PETM期间确定热带SST反应.
- 为了限制热带太平洋地区变暖的程度.
- 估计与此相关的大气二氧化碳 (pCO2) 的增加.
主要方法:
- 来自热带太平洋沉积物核心的浮游生物菌的分析.
- 配对氧同位素和/比率测量.
- 通过地化学代理来重建过去的海面温度.
主要成果:
- 热带太平洋的SST在PETM期间增加了4°C至5°C.
- 这种变暖相当于高度地区的温度升高.
- 结果表明大气pCO2的大幅上升2.
结论:
- 热带海洋在PETM期间经历了显著的变暖.
- 由于大气pCO2的大幅增加,PETM的驱动力是大气pCO2的大幅增加,可能比旧世晚期水平高3-4倍.
- 来自的地化学代理对于重建过去的气候事件至关重要.
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