在新世界-旧世界接触后,调和冰芯CO2和土地利用变化
Amy C F King1, Thomas K Bauska2, Edward J Brook3
1British Antarctic Survey, Cambridge, UK. amyking@bas.ac.uk.
Nature communications
|March 5, 2024
概括
大气中的二氧化碳 (CO2) 从冰芯的记录显示,在公元1610年左右逐渐减少,而不是突然下降. 这一发现支持美洲在历史接触后的土地利用变化.
科学领域:
- 古气候学 古气候学
- 大气化学 大气化学
- 地球系统科学 地球系统科学
背景情况:
- 冰芯记录提供了过去2000年大气二氧化碳 (CO2) 水平的关键数据.
- 了解历史的二氧化碳波动为当前的人为增加和全球碳循环动态提供了背景.
- 在二氧化碳记录中的某些历史间隔仍然不确定,需要进一步调查.
研究的目的:
- 介绍新测量的二氧化碳和甲 (CH4) 从Skytrain冰芯跨越1450年至1700年.
- 在现有的冰芯记录中重新评估公元1610年左右观察到的二氧化碳减少.
- 调查现代早期二氧化碳变化的驱动因素,特别是与土地利用有关的因素.
主要方法:
- 在Skytrain冰芯中分析CO2和CH4度.
- 对二氧化碳数据的统计评估,以确定潜在的工件.
- 冰芯数据与气候模型和历史土地使用场景的比较.
主要成果:
- 从公元1450年至1700年间的天际火车冰芯中获得了二氧化碳测量结果.
- 从公元1516年到公元1670年,每十年二氧化碳逐渐减少0.5ppm,与之前建议的急剧下降形成鲜明对比.
- 在此期间,推断的土地碳吸收量为每十年2.6 PgC.
结论:
- 在一些记录中,公元1610年左右的突然二氧化碳下降可能是一个文物,而不是真实的大气事件的反映.
- 观察到的二氧化碳的逐渐减少支持了美洲接触后土地利用重组的模型.
- 在公元1610年,二氧化碳的快速变化与即使是极端的土地利用变化场景也是不一致的,这凸显了准确的二氧化碳重建的重要性.
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