Pattern of retreat and disintegration of the Larsen B ice shelf, Antarctic Peninsula
Pattern of retreat and disintegration of the Larsen B ice shelf, Antarctic Peninsula
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DOI：
10.3189/172756404781814005
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发表时间：
2004-01-01
期刊：
影响因子：
--
通讯作者：
Rott, H
中科院分区：
文献类型：
--
作者：
Rack, W;Rott, H
利用1995年1月至2003年5月期间获得的卫星图像分析了南极半岛拉森B冰架的退缩及其北方部分的崩塌。在2002年3月的一个多星期里，在1995年以来的一段稳定撤退之后，2300公里（2）的冰架破裂成许多小冰山。这种快速的崩溃发生在一个异常温暖的夏季结束时，经过多年的减少表面净物质平衡，冰变薄，流动加速和裂缝扩大。冰架面积从1995年1月的11512平方公里减少到2002年3月的3463平方公里和2003年4月的2667平方公里。地球资源卫星合成孔径雷达图像被用来确定具有不同表面形态的冰盾区，这些冰盾区产生了不同大小和形状的冰山。与1995年的Larsen A相似的后退和破裂模式表明，由丰富的表面熔体增强的破裂起了关键作用。此外，最近的变化的地面和残留的浮冰拉森B北部的环境卫星先进的合成孔径雷达（ASAR）图像分析到2003年夏天，显示显着的损失，这些冰柱部分解体在1995年和2002年的上游的地面冰。
The retreat of the Larsen B ice shelf, Antarctic Peninsula, and the collapse of its northern section are analyzed using satellite images acquired between January 1995 and May 2003. Over 1 week during March 2002, after a period of steady retreat since 1995, 2300 km(2) of the ice shelf broke up into many small icebergs. This rapid collapse occurred at the end of an exceptionally warm summer, and after a multi-year period of decreasing surface net mass balance, ice thinning, flow acceleration and widening of rifts. The ice-shelf area decreased from 11512 km(2) in January 1995 to 3463 kM2 in March 2002, and 2667 km(2) in April 2003. ERS synthetic aperture radar (SAR) images were used to identify iceshelf zones with different surface morphology, which generated icebergs of different sizes and shapes. The pattern of retreat and break-up, similar to that of Larsen A in 1995, suggests that fracturing enhanced by abundant surface melt played a key role. In addition, the recent changes of grounded and residual floating ice north of Larsen B are analyzed by means of Envisat advanced synthetic aperture radar (ASAR) images up to summer 2003, showing significant loss of grounded ice upstream of those iceshelf sections which disintegrated in 1995 and 2002.