通过生产率反,在古世/新世边界结束全球变暖
S Bains1, R D Norris, R M Corfield
1Department of Earth Sciences, University of Oxford, UK. santo.bains@earth.ox.ac.uk
Nature
|September 23, 2000
概括
古世/新世热量最大值导致了全球变暖. 提高海洋生产力和有机碳埋葬可能通过去除大气中的二氧化碳来降温地球.
科学领域:
- 古气候学 古气候学
- 地质化学 地质化学
- 海洋学 海洋学 海洋学
背景情况:
- 古世/新世热极值 (PETM) 涉及5500万年前全球迅速变暖 (5-7°C).
- 这一事件很可能是由甲释放引发的,作为地球对高二氧化碳反应的模型.
- 一个潜在的反机制涉及有机碳出口和埋葬在深海的增加.
研究的目的:
- 调查全球变暖,海洋生产力和PETM期间的碳埋葬之间的联系.
- 为拟议的生物地球化学反循环提供地质证据.
主要方法:
- 对两个海洋钻井核心的分析.
- 测量生物原积累率作为出口古生产力的代理.
- 检查delta13C异常值的研究.
主要成果:
- 最高的生物积率恰逢全球最高气温和delta13C外游.
- 德尔塔13C值的快速回归表明气候迅速恢复.
- 生物积率与温度有很强的相关性.
结论:
- 该研究提供了强有力的证据,证明在PETM期间有机碳出口和埋葬的强化.
- 这一过程可能在冷却温室气候方面发挥了关键作用.
- 支持通过有机物沉积有效地去除大气中的二氧化碳.
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