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在过去的三个世纪里,北太平洋地区的气候变化
G W K Moore1, Gerald Holdsworth, Keith Alverson
1Department of Physics, University of Toronto, Toronto, Ontario M5S 1A7, Canada. moore@atmosp.physics.utoronto.ca
Nature
|December 3, 2002
概括
洛根山301年的冰芯记录揭示了与北美气候模式相关的积雪趋势. 这些代理数据扩展了历史气候变化研究,显示了自19世纪中叶以来的变暖趋势.
科学领域:
- 气候学 气候学 气候学
- 古气候学 古气候学
- 冰川学的冰川学
背景情况:
- 仪器气候记录往往太短,无法研究长期气候变化.
- 代理数据,如冰芯,对于重建过去的气候条件至关重要.
- 主导的气候模式,如太平洋北美模式和太平洋十年振荡,需要扩展记录进行全面分析.
研究的目的:
- 重建北美西北部洛根山301年的积雪记录.
- 使用代理数据调查积雪和主要气候模式之间的关系.
- 扩大对从小冰河时代到近期变暖时期的气候变化理解.
主要方法:
- 来自洛根山 (海拔5340米) 冰芯的301年积雪记录的分析.
- 冰芯记录与太平洋北美模式和太平洋十年振荡的仪器数据的比较.
- 统计分析以确定积雪和气候变化的趋势和相关性.
主要成果:
- 洛根山积雪记录与仪器时期的太平洋北美模式密切相关.
- 在19世纪中叶之后,雪积累的积极和加速趋势被观察到.
- 这一趋势与区域变暖和太平洋北美模式和太平洋十年振荡的世俗变化相平行.
结论:
- 301年的冰芯记录为了解北美西北部过去的气候变化提供了有价值的代理数据.
- 积雪趋势表明,自19世纪中叶以来,气候变暖趋势显著,这与主要气候振荡的变化有关.
- 这项研究强调了冰芯记录对于将气候研究扩展到仪器限制之外的重要性.
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