Constraints on the Greenland Ice Sheet since the Last Glacial Maximum from sea-level observations and glacial-rebound models
Constraints on the Greenland Ice Sheet since the Last Glacial Maximum from sea-level observations and glacial-rebound models
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DOI：
10.1016/j.quascirev.2003.11.001
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发表时间：
2004-05-01
影响因子：
4
通讯作者：
Lambeck, K
中科院分区：
文献类型：
--
作者：
Fleming, K;Lambeck, K
格陵兰冰盖（GIS）的范围内的变化的地貌描述相结合的冰川均衡调整模型再现格陵兰海平面的历史，因为末次冰期最大（LGM）。由于格陵兰岛以外的冰负荷变化，对格陵兰岛周围过去海平面变化的贡献相当大（+/- 10米）。而今天仍然贡献了几毫米yr（-1）的上升。格陵兰岛周围的相对海平面的变化，在地理信息系统的均衡的贡献，发现迭代扰动的初步冰模型与不同的末次冰期的程度和冰消开始时间。由此产生的，一阶模型，提供了观测和预测的海平面之间的最佳协议贡献3.1和1.9米水当量的额外的冰相对于现今的冰体积在LGM和新仙女木，分别。大多数地区的地理信息系统似乎没有延伸到大陆架上很远，例外的是格陵兰西南部最南端和格陵兰东部北方，以及格陵兰西北部和因纽特冰盖的合并处。自末次冰期以来，沿着现今外海岸的冰厚变化> 500英寸，沿着现今冰缘的某些部分> 1500英寸。所观察到的中晚期全新世海平面下降到低于现今的水平，随后在某些地区看到海侵意味着地理信息系统后退到现今的边缘后面的距离为40公里的顺序前readvancing。(C)2003爱思唯尔有限公司。保留所有权利。
Geomorphological descriptions of changes in the extent of the Greenland Ice Sheet (GIS) have been combined with glacial-isostatic-adjustment models to reproduce the sea-level history of Greenland since the Last Glacial Maximum (LGM). The contribution to past sea-level change around Greenland due to ice-load changes outside of that region has been considerable (+/- 10's of meters). while still contributing a rise of several mm yr(-1) today. The isostatic contribution to relative sea level around Greenland from changes in the GIS is found by iteratively perturbing preliminary ice models with different LGM extents and deglaciation starting times. The resulting, first-order model that provides the best agreement between observed and predicted sea level contributes 3.1 and 1.9 m water-equivalent of additional ice relative to present-day ice volumes at the LGM and Younger Dryas, respectively. The GIS in most areas does not appear to have extended far onto the continental shelf, the exceptions being southern-most Southwest Greenland and northern East Greenland, as well as at the coalescence of the Northwest Greenland and Innuitian Ice Sheets. Changes in ice thickness since the LGM were > 500 in along the present-day outer coast and > 1500 in along some parts of the present-day ice margin. The observed mid- to late-Holocene fall in sea level to below the present-day level and the subsequent transgression seen in some areas implies that the GIS retreated behind the present-day margin by distances of the order of 40 km before readvancing. (C) 2003 Elsevier Ltd. All rights reserved.