快速底部融化在南极冰盖接地线附近普遍存在
Eric Rignot1, Stanley S Jacobs
1Jet Propulsion Laboratory, California Institute of Technology, Mail Stop 300-235, Pasadena, CA 91109-8099, USA. eric@adelie.jpl.nasa.gov
概括
南极冰川从下面融化的速度比以前认为的要高. 海洋温度的升高显著加快了这种基底融化,威胁到冰架和冰川的深水进入.
科学领域:
- 冰川学的冰川学
- 海洋学 海洋学 海洋学
- 气候科学 气候科学
背景情况:
- 南极冰层的消失导致全球海平面上升.
- 在接地线上了解冰与海洋的相互作用对于预测未来的冰排放至关重要.
研究的目的:
- 量化南极出口冰川的基本融化速度.
- 为了研究海洋温度和冰川融化的关系.
主要方法:
- 卫星雷达干扰测量被用来测量融化速率.
- 分析的重点是靠近接地线的大型出口冰川.
主要成果:
- 观察到的底部融化率明显高于之前的假设.
- 融化速度每年增加1米,每增加0.1°C的海洋温度.
- 有直接深水接入接地线的冰川显示出更高的脆弱性.
结论:
- 基底融化是影响南极冰的稳定性的关键过程.
- 海洋温度上升对南极冰川和冰架构构成了重大威胁.
- 准确的融化速度数据对于气候模型和海平面上升预测至关重要.
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