类似于ENSO的强迫海洋初级生产在晚期普莱斯托时代
L Beaufort1, T de Garidel-Thoron, A C Mix
1CNRS-CEREGE, BP 80, 13545 Aix-en-Provence Cedex 04, France.
Science (New York, N.Y.)
|September 29, 2001
概括
在赤道太平洋和印度洋的海洋生产力随着冰河时代和地球倾斜而波动. 这些变化影响了大气中的二氧化碳水平,影响了全球气候.
科学领域:
- 古代海洋学 古代海洋学 古代海洋学
- 海洋生态海洋生态学
- 气候科学 气候科学
背景情况:
- 了解过去的海洋初级生产力对于预测未来的气候变化至关重要.
- 赤道印太地区是全球海洋动态和碳循环的关键区域.
研究的目的:
- 重建印度洋和太平洋赤道地区海洋初级生产率的晚期普世变化.
- 调查这些生产力变化的驱动因素,包括冰川-冰川间周期和轨道强迫.
- 评估赤道生产率与大气二氧化碳水平之间的关系.
主要方法:
- 在九个深海沉积物核心中保存的纳米浮游生物群落的分析.
- 对纳米浮游生物变化的定量评估,以推断过去的初级生产力.
- 生产力记录的光谱分析和与气候代理 (例如,氧同位素) 和大气二氧化碳记录的比较.
主要成果:
- 在赤道印太地区的海洋初级生产力在晚期普莱斯托纪期间有显著的变化.
- 生产率的变化主要是由冰川 - 间冰川周期和东 - 西热线斜率的前行控制的变化驱动的.
- 在氧同位素比率的变化之前,前cession驱动的生产率变化发生了变化,这表明它们不是冰盖波动的结果.
- 生产力记录中的3万年光谱峰值与大气二氧化碳的类似峰值相匹配,表明赤道生产力和二氧化碳水平之间存在联系.
结论:
- 轨道强迫,特别是前行,通过热动态显著影响赤道太平洋和印度洋的生产力.
- 赤道生物生产力在调节大气二氧化碳度方面发挥着重要作用.
- 这些发现突出了海洋学过程,轨道循环和全球碳循环在调节地球气候方面的相互联系.
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