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在最后一个冰川时期,陆地温度降低了6摄氏度
Alan M Seltzer1, Jessica Ng2, Werner Aeschbach3
1Marine Chemistry and Geochemistry Department, Woods Hole Oceanographic Institution, Woods Hole, MA, USA. aseltzer@whoi.edu.
Nature
|May 13, 2021
概括
在最后的冰川最大期 (LGM) 中,全球的冷却是显著的. 古代地下水中的高贵气体显示,低度陆地表面的温度降低了5.8°C,这有助于估计气候敏感性.
科学领域:
- 古气候学
- 地质化学
背景情况:
- 在最后的冰川最大期 (LGM) 估计全球冷却对于了解地球气候敏感性至关重要.
- 低度温度的差异阻碍了准确的气候重建.
- 由于其物理性质,地下水中的高贵气体提供了可靠的方法来重建过去的陆地表面温度.
研究的目的:
- 填补低度陆地LGM温度记录中的数据缺口.
- 提供LGM土地表面温度的空间综合重建.
- 限制地球气候敏感性的估计.
主要方法:
- 在古代地下水中溶解的贵重气体 (如,,) 的分析.
- 使用高温气体的可溶性作为过去温度的代理.
- 在统一的物理框架内解释四十年的全球地下水贵重气体数据.
主要成果:
- 在LGM期间,在低海拔,低至中度的陆地表面 (45°S至35°N) 显示出5.8±0.6°C的显著降温.
- 包含了来自六大洲的新热带记录和大量数据.
- 最近的海洋代理数据同化重建得到了广泛的支持,表明气候敏感性更高.
结论:
- 贵族气体古热法为低度的陆地区域提供了可靠的LGM温度数据.
- 重建的冷却支持显示气候敏感度高于先前估计的模型.
- 这项研究增强了我们对冰川时期全球气候动态的理解.
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