概括
全球海平面每年上升超过1毫米. 新的数据表明,这种上升可能是由冰盖和冰川的融化解释的,特别是如果巴伦茨海在18000年前被冰覆盖.
科学领域:
- 地质物理学 地质物理学
- 冰川学的冰川学
- 海洋学 海洋学 海洋学
背景情况:
- 潮计数据显示,全球海平面上升超过每年1毫米.
- 海平面上升的非恒星成分可能归因于冰川和冰盖造成的质量损失.
- 了解冰盖动态对于预测未来海平面变化至关重要.
研究的目的:
- 调查正在进行的冰质量损失作为观察到的海平面上升的驱动因素的合理性.
- 利用卫星地质数据来约束冰盖行为模型.
主要方法:
- 使用潮计观测对海平面长期世俗变化的分析.
- 卫星激光测距 (SLR) 和非常长基线干扰测量 (VLBI) 数据的应用.
- 地测数据 (日长,极运动) 与冰块质量平衡场景的相关性.
主要成果:
- 全球海平面以每年超过1毫米的速度上升.
- 卫星地测数据为冰块质量损失假设提供了限制.
- 如果巴伦茨海在最后一次冰川最大期期间承载了相当大的冰盖,那么质量损失假设是合理的.
结论:
- 世界上冰盖和冰川的持续质量损失是观察到的非星际海平面上升的合理解释.
- 卫星地质测量为冰盖的动态及其对海平面变化的贡献提供了关键的见解.
- 重建过去的冰盖面积,如巴伦茨海,对于验证当前的气候和海平面模型至关重要.
相关概念视频
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01:20Variation in Acceleration due to Gravity near the Earth's Surface
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01:28Apparent Weight and the Earth's Rotation
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01:26Influence of Earth's Curvature and Atmospheric Refraction on Leveling
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