最近的格陵兰岛冰块质量损失是由卫星重力观测的排水系统造成的
S B Luthcke1, H J Zwally, W Abdalati
1Planetary Geodynamics Laboratory, Code 698, NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA. Scott.B.Luthcke@nasa.gov
概括
从2003年至2005年,格陵兰冰盖每年损失101千亿冰,主要是在较低的海拔地区. 这表明它从20世纪90年代的近平衡状态发生了重大转变.
科学领域:
- * 冰川学和气候科学
- * 地球观测和地质物理学
背景情况:
- * 格陵兰冰盖的质量平衡对于了解全球海平面上升至关重要.
- *以前的冰损失估计有所不同,需要精细的区域分析.
研究的目的:
- *使用区域排水系统数据量化格陵兰冰盖的质量变化.
- *分析2003年至2005年冰块质量损失的空间和时间模式.
主要方法:
- *利用了重力恢复和气候实验 (GRACE) 任务观测结果的局部质量度分析.
- * 根据格陵兰冰盖的特定排水系统区域的质量变化.
主要成果:
- * 2003年至2005年间,冰总损失平均每年为101+/- 16千兆.
- *较低的海拔地区经历了显著的质量损失 (每年155千亿),季节性周期明显.
- *较高的海拔 (2000米以上) 显示每年增加54千兆.
结论:
- * 格陵兰冰盖在2003-2005年期间表现出相当大的负质量平衡,这与20世纪90年代相比是显著的变化.
- *区域分析显示了明显的质量变化模式,较低的海拔是导致整体冰损失的关键因素.
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