类似的融水对冰川海平面变化的贡献来自南极和北方冰盖
Eelco J Rohling1, Robert Marsh, Neil C Wells
1Southampton Oceanography Centre, Southampton SO14 3ZH, UK. e.rohling@soc.soton.ac.uk
Nature
|August 27, 2004
概括
在最后一个冰川时期,南极和北半球的冰盖均为海平面上升做出了同等的贡献. 这项研究量化了来自两极地区的融水贡献.
科学领域:
- 古气候学 古气候学
- 冰川学的冰川学
- 海洋学 海洋学 海洋学
背景情况:
- 7万5千至2万年前的时期经历了显著的气候和海平面变化.
- 南大洋的冰碎片表明南极融水影响了海平面的变化,以及北方冰盖的贡献.
研究的目的:
- 确定南极和北极冰盖融化水对海平面变化的相对贡献.
- 模拟不同融化水释放对海洋氧同位素分布的影响.
主要方法:
- 利用一个中间复杂度模型来模拟来自极地地区的融化水释放.
- 模型模拟与来自沉积物核心的氧同位素数据进行了比较.
主要成果:
- 推断南极和北极冰盖大约在65,000至35,000年前对海平面上升作出了同等贡献.
- 每个极地在此期间对海平面上升贡献了大约15米.
结论:
- 该研究提供了对过去海平面波动期间融化水源的定量见解.
- 推断出的南极冰体量减少与上一次脱冰期间的融水脉冲1A的减少相当.
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