伊比利亚边缘表面海洋冷却导致在海洋同位素阶段6期间的新鲜化突然冷却事件
Hongrui Zhang1, Yongsong Huang2, Reto Wijker3
1Geological Institute, ETH Zürich, 8092, Zürich, Switzerland. zhh@ethz.ch.
Nature communications
|September 4, 2023
概括
在伊比利亚边缘古气候记录中高C37:4%表明表面冷却,而不是清新. 表面清新放大了千年气候冷却事件,但并不总是引发它们.
科学领域:
- 古气候学 古气候学
- 海洋地球化学 海洋地球化学
- 海洋学 海洋学 海洋学
背景情况:
- 伊比利亚边缘古气候记录为突如其来的气候变化机制提供了见解.
- 之前的研究将基不和 (C37:4%) 与表面冷却和清新联系起来.
- 最近的研究质疑C37:4%和度之间的直接联系在基生产者 (coccolithophores) 中.
研究的目的:
- 为了澄清在伊比利亚边缘古气候记录中高C37:4%的驱动因素.
- 为了区分海面温度 (SST) 和盐度对子组成的影响.
- 为了研究表面清新和千年气候冷却事件之间的关系.
主要方法:
- 详细的基测量以确定生产者.
- 对于氨基的Mg/Ca和氧同位素分析来重建盐度.
- 从伊比利亚边缘的高分辨率古气候数据分析.
主要成果:
- 证实了基仅由科利托产生的.
- 高C37:4%值与海面温度 (SST) 的降低相关,而不是盐度的降低.
- 表面清新事件放大了现有的冷却,但并没有始终启动冷却.
结论:
- C37:4%指数是伊比利亚边缘古海洋学SST重建的可靠代理.
- 千年气候变化涉及温度和盐度之间的复杂相互作用.
- 表面清新可以作为反机制,放大冷却事件.
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