Evolution of Rhonegletscher, Switzerland, over the past 125 years and in the future: application of an improved flowline model
Evolution of Rhonegletscher, Switzerland, over the past 125 years and in the future: application of an improved flowline model
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DOI：
10.3189/172756407782871143
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发表时间：
2007-10
影响因子：
2.9
通讯作者：
S. Sugiyama;A. Bauder;Conradin Zahno;M. Funk
中科院分区：
文献类型：
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作者：
S. Sugiyama;A. Bauder;Conradin Zahno;M. Funk
摘要为了研究瑞士Rhonegletscher的过去和未来的演变，开发了一个流线模型，该模型比传统的流带模型更准确地包括谷形效应。在模型中，在一个网格点的冰通量计算的二维冰流模型应用于山谷横截面。结果表明，低估的积累面积，这似乎是一个普遍的问题，流线模型所产生的模型的一维性质。校正的质量平衡与平衡线高度（ELA）的变化，这是重建1878年至2003年期间的温度和降水记录，在过去的125年运行的模式。该模型令人满意地再现了终点位置和总冰量的变化，这些变化是通过分析旧地图和航空照片获得的地面数字高程模型得出的。这表明，当可以确定准确的物质平衡时，该模型有潜力模拟冰川演变。Rhonegletscher的未来演变是通过三个质量平衡条件来评估的：1994-2003年期间的平均值，以及过去50年来最负（2003年）和最正（1978年）的质量平衡值。该模型预测的三种条件下50年后的体积变化分别为-18%，-58%和+38%。
Abstract To study the past and future evolution of Rhonegletscher, Switzerland, a flowline model was developed to include valley shape effects more accurately than conventional flowband models. In the model, the ice flux at a gridpoint was computed by a two-dimensional ice-flow model applied to the valley cross-section. The results suggested the underestimation of the accumulation area, which seems to be a general problem of flowline modelling arising from the model’s one-dimensional nature. The corrected mass balance was coupled with the equilibrium-line altitude (ELA) change, which was reconstructed for the period 1878–2003 from temperature and precipitation records, to run the model for the past 125 years. The model satisfactorily reproduced both changes in the terminus position and the total ice volume derived from digital elevation models of the surface obtained by analyses of old maps and aerial photographs. This showed the model’s potential to simulate glacier evolution when an accurate mass balance could be determined. The future evolution of Rhonegletscher was evaluated with three mass-balance conditions: the mean for the period 1994–2003, and the most negative (2003) and positive (1978) mass-balance values for the past 50 years. The model predicted volume changes of –18%, –58% and +38% after 50 years for the three conditions, respectively.