在代晚期的稳定碳循环气候关系
Urs Siegenthaler1, Thomas F Stocker, Eric Monnin
1Climate and Environmental Physics, Physics Institute, University of Bern, Sidlerstrasse 5, CH-3012 Bern, Switzerland.
概括
大气中的二氧化碳 (CO2) 含量超过65万年,表明与南极气候有着稳定的关系. 尽管在早期的冰川周期中二氧化碳的范围较窄,但二氧化碳的灵敏度保持不变.
科学领域:
- 古气候学 古气候学
- 大气科学 大气科学
- 南极研究南极研究
背景情况:
- 了解长期气候动态对于预测未来气候变化至关重要.
- 以前的冰芯记录提供了对过去大气组成和气候变化的洞察力.
研究的目的:
- 为了重建过去65万年的大气二氧化碳 (CO2) 度.
- 为了研究二氧化碳水平与南极气候在多个冰川周期中的关系.
主要方法:
- 使用EPICA Dome Concordia冰芯对大气中的二氧化碳度进行分析.
- 扩展沃斯托克二氧化碳记录到现在之前的65万年.
- 将二氧化碳数据与记录进行比较,以评估气候敏感性.
主要成果:
- 埃皮卡冰芯提供了可2记录,可以追溯到65万年前.
- 在公元43万年前,二氧化碳度在180至260 ppmv之间,比最近的冰川周期更窄.
- 南极气候对二氧化碳的敏感性在六个冰川周期中保持稳定.
结论:
- 大气中的二氧化碳和南极气候之间的长期关系至少在65万年里一直保持一致.
- 过去的冰川周期表现出稳定的二氧化碳气候敏感性,尽管二氧化碳度范围的变化.
- 这项研究增强了我们对地球气候系统对地球地质时间尺度上的温室气体波动的反应的理解.
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