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Updated: Jun 25, 2026

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Evolution of Staircase Structures in Diffusive Convection
Published on: September 5, 2018
在热带太平洋中期的普莱斯托时代过渡期
Martín Medina-Elizalde1, David W Lea
1Department of Earth Science, University of California Santa Barbara, Santa Barbara, CA 93106-9630, USA.
概括
普莱斯托纪中期的气候变化显示,海面温度 (SST) 振荡从41,000年周期变化到100,000年周期. 这些热带太平洋的SST变化先于冰体积转移,暗示大气中的二氧化碳是关键驱动因素.
科学领域:
- 古海洋学是古海洋学.
- 气候科学 气候科学
- 海洋地质 海洋地质学
背景情况:
- 普莱斯托时代中期过渡 (MPT) 标志着地球冰川 - 冰川间周期周期发生显著变化.
- 了解这种周期性转变的驱动因素对于预测未来气候动态至关重要.
研究的目的:
- 为了重建过去的海洋表面温度 (SSTs) 在西赤道太平洋温暖池在MPT期间.
- 调查热带太平洋SST,东太平洋冷舌SST和大陆冰体积变化之间的关系.
主要方法:
- 分析浮游生物菌/的比例,以建立一个SST记录.
- 沉积物核心的年代测定,以确定古气候事件的精确时间表.
主要成果:
- SST记录显示,冰川-冰川间振荡周期从41000年到10万年在MPT的变化,大约95万年前.
- 热带太平洋SST变化与东太平洋冷舌SST同步,但导致大陆冰体积变化.
结论:
- 热带太平洋SST变化的观察到的时间和性质表明,大气中的二氧化碳对辐射强迫的周期性发生了变化.
- 这种二氧化碳强迫转移被认为是普莱斯托纪中期过渡期间气候周期变化的主要原因.
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