APPLICATION OF SURFACE MATCHING FOR IMPROVED MEASUREMENTS OF HISTORIC GLACIER VOLUME CHANGE IN THE ANTARCTIC PENINSULA
APPLICATION OF SURFACE MATCHING FOR IMPROVED MEASUREMENTS OF HISTORIC GLACIER VOLUME CHANGE IN THE ANTARCTIC PENINSULA
复制标题
应用表面匹配改进南极半岛历史冰川体积变化的测量
DOI：
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发表时间：
2012
期刊：
影响因子：
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通讯作者：
S. Marsh
中科院分区：
文献类型：
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作者：
M. Kunz;J. Mills;P. Miller;Matt A. King;A. Fox;S. Marsh
气候记录显示，南极半岛正在迅速变暖。在过去几十年中，记录了冰架和冰川范围的巨大变化。绘制南极半岛最近的变化相对简单，因为越来越多的地球观测数据可以随时用于科学目的。然而，对该地区体积变化的长期测量很少，对20世纪世纪后半叶发生的变化知之甚少。尽管如此，历史观察是以档案航空立体摄影的形式提供的。然而，从历史数据中提取信息，即将其与最近的数据进行比较，并不是一件小事，而且迄今为止，这一数据源尽管潜力巨大，但在很大程度上仍未得到开发。这类图像通常以非数字格式存储，并可能随着时间的推移而退化。其他问题涉及元数据或地面控制不足。通常，这些困难导致多时间DEM的配准不良，这降低了后续的表面变化测量。这是访问档案数据集的基本限制之一。在这项研究中，最小二乘表面匹配技术，以克服这些挑战，实现可靠的注册多时相DEM。在20世纪60年代获得的两个南极半岛冰川的历史图像进行处理，提取DEM，随后比较来自现代ASTER卫星数据和航空摄影的DEM。通过表面匹配的方法，它表明，历史和现代数据集的配准精度可以显着提高。这使得能够在几十年的时间尺度上精确量化冰川海拔变化。在过去的40年里，观测到锋面冰川表面下降了50米。这项研究的结果可以更好地了解历史体积冰川的南极半岛的变化，并提供了一个有效的和自动化的方法，提高DEM配准。
Climate records show that the Antarctic Peninsula is rapidly warming. Dramatic changes in ice shelf and glacier extent have been recorded over the last few decades. Mapping recent changes in the Antarctic Peninsula is relatively straightforward, as increased amounts of earth observation data become readily available for scientific purposes. However, long term measurements of volumetric changes within the region are rare and less is known of changes which have occurred over the second half of the 20th Century. Nonetheless, historical observations are available in the form of archival aerial stereo-photography. However, extracting information from historical data, i.e. to compare it to recent data, is not trivial, and to-date, this data source remains largely untapped, despite its rich potential. Often such imagery is stored in non-digital format and may have degraded over time. Other problems relate to insufficient metadata or ground control. Typically these difficulties result in poor registration of multi-temporal DEMs, which degrade subsequent measurements of surface change. This is one of the fundamental limitations of accessing archival datasets. In this research a least squares surface matching technique is introduced to overcome these challenges and achieve reliable registration of multi-temporal DEMs. Historical imagery acquired in the 1960s for two Antarctic Peninsula glaciers is processed to extract DEMs, which are subsequently compared to DEMs derived from modern ASTER satellite data and aerial photography. Through the surface matching approach, it is shown that the registration accuracy of the historical and modern-day datasets can be improved significantly. This enables precise quantification of glacier elevation changes on a multi-decadal time scale. Frontal glacier surface lowering of up to 50 m was observed over the last ~4 decades. Results of this study allow a better understanding of historical volumetric glacier changes of the Antarctic Peninsula and provide an efficient and automated method for improved DEM co-registration.