调和不同的趋势和千年变化的全新纪温度
Jeremiah Marsicek1, Bryan N Shuman1, Patrick J Bartlein2
1Department of Geology and Geophysics, University of Wyoming, Laramie, Wyoming 82072, USA.
Nature
|February 2, 2018
概括
根据新的花粉数据, 这挑战了以前的北大西洋冷却推断,并与气候模型模拟保持一致.
科学领域:
- 古气候学
- 气候模型
背景情况:
- 人们认为Holocene时代 (过去的11,700年) 是由长期冷却主导的.
- 这种推断的冷却与全球强迫和气候模型模拟的变暖是具有挑战性的.
- 在北方中度地区特别存在差异, 海洋和沿海记录表明气候变冷.
研究的目的:
- 用北美和欧洲的亚化石花粉数据重建全新纪的温度趋势.
- 将现有的古气候重建与气候模型模拟之间的差异结合起来.
- 评估长期冷却作为主导的全新世纪趋势的有效性.
主要方法:
- 分析来自北美和欧洲642个地点的亚化石花粉.
- 基于花粉的温度重建与社区气候系统模型3 (CCSM3) 的模拟进行比较.
- 在花粉衍生和基于海洋的温度重建之间的相关性分析.
主要成果:
- 花粉数据显示,整个全新世纪的气候变暖一直持续到大约2000年前,这与之前的冷却推断相矛盾.
- 长期冷却的证据似乎仅限于北大西洋海洋记录.
- 早期的全新世大陆温度比过去两千年低2摄氏度,与CCSM3冰盖效应的模拟相一致.
结论:
- 全新纪的温度趋势主要是变暖,与气候模型模拟一致,挑战了主导的长期冷却概念.
- 海洋记录的差异凸显了潜在的季节性敏感性和区域性差异.
- 最近的升温使气温高于全新纪的平均值,
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