来自Fitzroya的3620年温度记录压缩了南美南部的树木环
概括
来自智利的3,622年的树记录显示了长期的温度波动. 该研究没有发现南美南部最近人为变暖的证据,突出显示了自然气候的变化.
科学领域:
- 古气候学 古气候学
- 登德罗年代学 登德罗年代学
- 气候科学 气候科学
背景情况:
- 了解过去的气候变化对于对当前气候变化的理解至关重要.
- 树环时间表为重建过去的温度提供了高分辨率的代理数据.
- 智利南部的Alerce树 (Fitzroya cupressoides) 为长期气候研究提供了一个独特的档案.
研究的目的:
- 通过使用树环,重建南美南部3622年的夏季温度记录.
- 调查长期温度趋势并确定显著变暖和变冷的时期.
- 根据代理和仪器数据评估该地区人为变暖的证据.
主要方法:
- 来自Fitzroya cupressoides的每年解决的树环宽度时间表的构建.
- 对树环数据与仪器温度记录进行校准.
- 对3622年温度重建的分析,以确定长期模式和异常.
主要成果:
- 夏季温度高于平均水平的最长间隔发生于公元前80年. 到公元160年.
- 从公元300年到470年以及公元1490年到1700年,长时间观察到低于平均水平的温度.
- 无论是Alerce树环数据还是仪器记录都没有显示出近几十年来南美南部 (35-44°S) 人为变暖的证据.
结论:
- 阿莱塞树为南美南部过去气候的重建提供了有价值的长期代理.
- 在过去的三千年里,该地区经历了显著的自然温度变化.
- 根据这项研究的发现,该地区目前的变暖趋势,如果有的话,不能归因于人类引起的原因.
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