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由于南极的融水导致的深海减速和变暖
Qian Li1, Matthew H England2, Andrew McC Hogg3
1Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA.
Nature
|March 29, 2023
概括
南极融水通过减少南极底水 (AABW) 的形成加速了深海的变暖. 这种由融水驱动的过程, 而不是风力或热力驱动, 影响了全球海洋循环和气候几个世纪.
科学领域:
- 海洋学
- 气候科学
- 冰川学
背景情况:
- 海洋循环对于全球热量,碳和营养循环至关重要.
- 在高南度地区观察到的深变暖缺乏明确的归因.
- 气候模型难以准确地反映极地海洋动态和冰盖融化的影响.
研究的目的:
- 调查深海变暖的驱动因素及其与循环变化的联系.
- 预测未来的海底变化,包括动态冰盖融化的影响.
- 确定南极融水与其他南极底层水的作用.
主要方法:
- 使用高分辨率的海洋冰模型.
- 模拟了30年来短暂的高排放情况.
- 分析了深海特性的变化,南极底部水 (AABW) 的形成,以及环极深水路径.
主要成果:
- 在高排放下, 预计全球变暖将加快.
- 南极融水的输入导致AABW收缩,使更温暖的水进入大陆架.
- 融水对AABW的特性,年龄和体积产生重大影响,导致深的变暖和老化.
结论:
- 南极的融水是深海翻转的关键驱动因素.
- 预计风力和热力对AABW的影响最小.
- 发现强调南极融水对海洋生态化学和全球气候的长期影响.
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