南半球气候变化是由北半球冰盖地形造成的
T R Jones1, W H G Roberts2, E J Steig3
1Institute of Arctic and Alpine Research, University of Colorado, Boulder, Colorado 80309-0450, USA.
Nature
|February 6, 2018
概括
西南极洲的气候变化在最后的冰川最大期是由于热带太平洋的强烈联系而高出两倍. 这种增加的可变性随着脱冰而显著下降.
科学领域:
- 古气候学
- 气候变化
- 冰川地质
背景情况:
- 北半球大冰盖和低温室气体在最后的冰川最大 (LGM) 显著改变了全球气候.
- 厄尔尼诺-南方振荡 (ENSO) 是短期气候变化的关键驱动因素,受冰川条件的影响.
- 了解冰川时期的高度气候变化仍然是一个挑战.
研究的目的:
- 在LGM期间重建和量化高度气候变化.
- 在冰川时期调查热带气候和西南极洲之间的远程连接.
- 了解脱冰对气候变化的影响.
主要方法:
- 来自西南极洲的高分辨率水同位素记录的分析.
- 气候模型模拟以解释古气候数据.
- 将LGM变异性与Holocene变异性的比较.
主要成果:
- 西南极洲的年间到十年气候变化在LGM期间几乎是Holocene的两倍.
- 这种变化与热带太平洋和西南极洲之间更强的远程连接有关.
- 受到北美冰盖影响的热带对流变化推动了这种增强的远程连接.
- 远程连接的强度在16000年至15000年前的降冰时期下降最快.
结论:
- 高度气候变化在LGM期间显著放大.
- 北美冰盖的动态在调节热带高度气候连接方面发挥了关键作用.
- 降冰导致气候变化大大减少.
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