南极海平面贡献的较低卫星重力测量估计
Matt A King1, Rory J Bingham, Phil Moore
1School of Civil Engineering and Geosciences, Newcastle University, Newcastle upon Tyne NE1 7RU, UK. m.a.king@newcastle.ac.uk
Nature
|October 23, 2012
概括
在南极洲,南极洲是南极洲.
科学领域:
- 地球科学 地球科学 地球科学
- 冰川学的冰川学
- 气候科学 气候科学
背景情况:
- 对南极洲冰块质量损失的估计有很大差异,影响了海平面上升预测.
- 冰川静态调整 (GIA) 模型中的不确定性显著影响了重力恢复和气候实验 (GRACE) 卫星数据的解释.
研究的目的:
- 通过使用新的GIA模型,改进南极洲冰块质量变化的估计.
- 通过解决GIA不确定性,提高GRACE衍生的冰质量损失数据的准确性.
主要方法:
- 开发了一个基于地质约束的新GIA模型,产生较低的GIA利率.
- 将新的GIA模型应用于99个月的GRACE卫星数据 (2002年8月至2010年12月).
- 分析了26个独立的南极排水盆地的冰质量变化.
主要成果:
- 估计整个大陆的冰块质量变化为 -69 ± 18 Gt yr ((-1) (+0.19 ± 0.05 mm yr ((-1) 相当于海平面).
- 这一估计远低于以往使用旧GIA模型的基于GRACE的估计.
- 冰块质量损失和加速集中在阿蒙森海沿岸盆地;西南极洲接近平衡,而东南极洲正在增加质量.
结论:
- 新的GIA模型显著降低了GRACE衍生冰块质量变化估计的不确定性.
- 南极洲对海平面上升的贡献得到了更准确的量化,并突出了区域差异.
- 未来的海平面上升预测可以通过更精确的南极冰动态数据来改进.
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