南极的表面温度和海拔高度在最后的冰川最大
Christo Buizert1, T J Fudge2, William H G Roberts3
1College of Earth Ocean and Atmospheric Sciences, Oregon State University, Corvallis, OR 97331, USA. christo.buizert@oregonstate.edu.
概括
这项研究揭示了南极洲的最后冰期最大降温,西南极洲降温10°C,东南极洲降温4-7°C. 这些发现使古气候数据与气候模型相协调.
科学领域:
- 古气候学
- 冰川学
- 南极研究
背景情况:
- 极地冰核中的水稳定同位素是关键温度代理.
- 校准这些代理是个挑战, 特别是在东南极洲.
- 了解过去的南极气候对于预测未来的气候变化至关重要.
研究的目的:
- 重建南极的最后一个冰期最大面冷却的幅度和空间模式.
- 将冰芯数据与全球气候模型输出进行比较.
- 为了调和不同古气候代理重建之间的差异.
主要方法:
- 分析7个南极冰芯的钻孔温度和状性质.
- 纳入冰芯空气含量数据以考虑地形变化.
- 重建温度与水同位素代理数据和气候模型模拟的比较.
主要成果:
- 西南极地区的表面温度与工业化前时期相比降低了约10°C.
- 东南极地区的冷却范围约为4°C至7°C.
- 在考虑地形变化时,东南极洲的重建冷却与气候模型保持一致,但低于对现代梯度进行校准的水同位素代理的估计.
结论:
- 这项研究提供了对南极的最后一次冰川最大冷却的精细估计.
- 在冰川时期发生的南极温度逆转有助于将新发现与水同位素观测相协调.
- 这项研究提高了南极古气候重建的可靠性.
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