证据表明,在北太平洋的深水产量,在早期的纪温暖间隔期间
1Department of Oceanography, Texas A&M University, College Station, Texas 77843-3146, USA. dthomas@ocean.tamu.edu
Nature
|July 2, 2004
概括
深海循环显著影响全球热传输. 古代的气候变化,特别是代的温暖,受到深水生产场所的变化的影响,而不是由它们驱动.
科学领域:
- 古海洋学是古海洋学.
- 气候科学 气候科学
- 地质化学 地质化学
背景情况:
- 深海循环是全球热传输的关键驱动力.
- 纪时代经历了极端的温暖,可能与海洋热传输有关.
- 海洋门户影响深水形成和循环模式.
研究的目的:
- 研究深海循环与古代气候之间的关系.
- 确定深水产量的变化,在古时代.
- 澄清循环变化与中世纪热量之间的因果关系.
主要方法:
- 来自两个太平洋沉积物核心的同位素记录的分析.
- 同位素数据与氧同位素记录的比较.
- 过去深水源和循环通道的重建.
主要成果:
- 证据表明,大约6500万年前,深水产量从南大洋转移到北太平洋.
- 在4000万年前,深水源的逆转回到南大洋.
- 循环的时间变化与代的温暖相关,但没有引起.
结论:
- 纪深水循环模式发生了显著的变化.
- 这些循环变化是极端热带的后果,而不是原因.
- 了解过去的海洋循环对于解释古气候数据至关重要.
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