Velocity map of the Thwaites Glacier catchment, West Antarctica
Velocity map of the Thwaites Glacier catchment, West Antarctica
复制标题
南极洲西部思韦茨冰川流域的速度图
DOI：
10.3189/172756504781830268
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发表时间：
2004
影响因子：
3.4
通讯作者：
S. Dech
中科院分区：
文献类型：
--
作者：
O. Lang;B. Rabus;S. Dech
摘要利用欧洲遥感卫星合成孔径雷达（ERS SAR）1995-2000年的23幅上升轨道和22幅下降轨道干涉图，绘制了西南极洲Thwaites冰川的二维表面速度图。速度图覆盖了从阿蒙森海岸到卫星轨道南部转折点的175 500平方公里，包括80%以上的思韦茨流域。相对速度误差<10%，除了极少数区域（约占总面积的5%）的不利外观几何形状。六个独立的支流被确定，他们的中心线速度增加从0在集水区边界的~0.3公里a-1时，他们加入的主要冰川干线。在主干上，接地线处的速度增加到~1.8 km a-1，浮舌处的速度增加到3.6 km a-1。在邻近的松岛冰川，没有发现强烈的纵向速度梯度，除了接地线附近。在预期的误差范围内，流型在时间上是静止的，即流线与速度幅值模式所显示的流动轮廓一致。因此，支流边界的潜在时间偏移必须<4.4 m a-1。
Abstract The two-dimensional surface velocity of Thwaites Glacier, West Antarctica, was mapped with 23 ascending- and 22 descending-orbit European Remote-sensing Satellite synthetic aperture radar (ERS SAR) interferograms (time range 1995–2000). The velocity map covers 175 500 km2 from the Amundsen Coast to the southern turning point of the satellite orbit and comprises >80% of the Thwaites catchment. Relative velocity errors are <10% except for rare regions (about 5% of the total area) of unfavorable look geometry. Six individual tributaries were identified; their center-line velocities increase from 0 at the catchment boundary to ~0.3 km a–1 when they join the main glacier trunk. On the main trunk, velocity increases to ~1.8 km a–1 at the grounding line and 3.6 km a–1 on the floating tongue. As at neighboring Pine Island Glacier, no strong longitudinal velocity gradients are found except near the grounding line. Within expected error bounds, the flow pattern appears temporally stationary, i.e. flowlines agree with the delineation of flow suggested by the pattern of velocity magnitude. A potential temporal shift of tributary boundaries must consequently be <4.4 m a–1.