Is climate change responsible for changing landslide activity in high mountains?
Is climate change responsible for changing landslide activity in high mountains?
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DOI：
10.1002/esp.2223
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发表时间：
2012-01-01
影响因子：
3.3
通讯作者：
Korup, Oliver
中科院分区：
文献类型：
--
作者：
Huggel, Christian;Clague, John J.;Korup, Oliver
气候变化在许多区域日益明显，表现为平均、最低和最高温度的上升以及更强烈的暴雨。这些变化的一个重要后果可能是高山滑坡的增加。然而，还需要更多的研究来检测与当代气候相关的滑坡规模和频率的变化，特别是在高山地区的冰川，永久冻土和积雪。这些地区不仅对温度和降水的变化很敏感，而且即使在气候稳定的情况下，滑坡也无处不在。我们分析了一系列灾难性的边坡失稳，发生在欧洲，美洲和高加索山脉自20世纪90年代末。我们区分岩石和冰雪崩，从冰川消融地区的泥石流，涉及与冰川和河流过程的动态相互作用的山体滑坡。对这些事件的分析表明，高山斜坡稳定性的几个重要控制因素，包括：积雪和冰对变暖的非线性响应;地下基岩的三维变暖及其与场地地质的关系;伴随着新沉积物暴露的冰川消融;以及降水和温度的短期综合影响。基于一些案例研究，我们提出以下机制可以显著改变滑坡的规模和频率，从而在变暖条件下产生灾害：（1）作用于块体运动过程的正反馈，在初始气候刺激之后，块体运动过程可能独立于气候变化而演变;（3）泥沙和冰的储存涉及重要的滞后时间效应。版权所有（C）2011约翰威利父子有限公司
Climate change, manifested by an increase in mean, minimum, and maximum temperatures and by more intense rainstorms, is becoming more evident in many regions. An important consequence of these changes may be an increase in landslides in high mountains. More research, however, is necessary to detect changes in landslide magnitude and frequency related to contemporary climate, particularly in alpine regions hosting glaciers, permafrost, and snow. These regions not only are sensitive to changes in both temperature and precipitation, but are also areas in which landslides are ubiquitous even under a stable climate. We analyze a series of catastrophic slope failures that occurred in the mountains of Europe, the Americas, and the Caucasus since the end of the 1990s. We distinguish between rock and ice avalanches, debris flows from de-glaciated areas, and landslides that involve dynamic interactions with glacial and river processes. Analysis of these events indicates several important controls on slope stability in high mountains, including: the non-linear response of firn and ice to warming; three-dimensional warming of subsurface bedrock and its relation to site geology; de-glaciation accompanied by exposure of new sediment; and combined short-term effects of precipitation and temperature. Based on several case studies, we propose that the following mechanisms can significantly alter landslide magnitude and frequency, and thus hazard, under warming conditions: (1) positive feedbacks acting on mass movement processes that after an initial climatic stimulus may evolve independently of climate change; (2) threshold behavior and tipping points in geomorphic systems; (3) storage of sediment and ice involving important lag-time effects. Copyright (C) 2011 John Wiley & Sons, Ltd.