海洋碳循环加速,这是由于米奥生气候最佳时期的构造性脱气而导致的
Fenghao Liu1, Jinlong Du1, Enqing Huang1
1State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092, China.
Science bulletin
|January 13, 2024
概括
在米奥森气候最佳时期,海洋碳循环的变化导致了长时间气候变化. 热带气候过程在温暖的地球条件下调节了碳循环,与以后极地冰盖的影响不同.
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:
- 苗代气候最佳时期 (MCO) 经历了与火山活动的巨大碳排放相关的显著全球变暖.
- 构造性碳排气对气候变化和碳循环在MCO期间的相互作用的确切影响尚未完全理解.
研究的目的:
- 在MCO期间调查海洋碳循环和气候-冰系统之间的关系.
- 确定构造性碳排气在这个温暖时期对气候和碳循环动态的影响.
主要方法:
- 分析高分辨率的基菌氧 (δ18O) 和碳 (δ13C) 同位素记录.
- 时间进化阶段分析应用于新的和公布的全球海洋数据.
- 敏感性分析和气候模型模拟.
主要成果:
- 在MCO期间,海洋碳循环变化导致气候-冰层系统 (δ13C--δ18O) 在405,000年的偏心周期上出现.
- 这与Oligo-Miocene中先前观察到的气候--碳 (δ18O--δ13C) 模式形成鲜明对比.
- 升高的CO2度加剧了低度的水文循环,增强了海洋碳循环对偏心强迫的敏感性.
结论:
- 热带气候过程是MCO温暖政权期间碳循环变化的关键调节者.
- 这与极地冰盖动力学在调节后期普利奥-普莱斯托时代碳循环中的主导作用不同.
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