Glacier change and glacial lake outburst flood risk in the Bolivian Andes
Glacier change and glacial lake outburst flood risk in the Bolivian Andes
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DOI：
10.5194/tc-10-2399-2016
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发表时间：
2016-10-20
期刊：
影响因子：
5.2
通讯作者：
Hoffmann, Dirk
中科院分区：
文献类型：
--
作者：
Cook, Simon J.;Kougkoulos, Ioannis;Hoffmann, Dirk
玻利维亚安第斯山脉的冰川是安第斯山脉城市和山区社区的重要水资源，但近几十年来对其范围的变化进行评估的工作相对较少。在许多山区，冰川退缩伴随着冰前湖的发展，这可能造成冰湖溃决洪水（GLOF）的危险。然而，没有研究评估了这些湖泊在玻利维亚的发展，尽管最近这里发生了GLOF事件。我们对卫星图像的测绘显示，1986年至2014年期间，玻利维亚东方科迪勒拉山脉的总体面积缩小了228：1 +/- 22：8 km（2）（43.1%）。Tres Cruces地区的收缩率最高（47.3%），其次是Cordillera Apolobamba（43.1%）和Cordillera真实的（41.9%）。随着冰川的消退，越来越多的冰前湖泊出现，这与大多数其他冰川消退山脉的趋势一致，尽管冰接触湖泊的数量有所减少。其原因尚不清楚，但在整个研究期间，湖泊变化的模式变化很大，这表明随着冰层继续消退，需要监测未来的湖泊发展。最终，我们使用2014年的冰前湖泊数据库来评估玻利维亚安第斯山脉的GLOF风险。我们确定了25个对下游社区和基础设施构成潜在GLOF威胁的湖泊。我们认为，进一步研究潜在的GLOF的影响是迫切需要的。
Glaciers of the Bolivian Andes represent an important water resource for Andean cities and mountain communities, yet relatively little work has assessed changes in their extent over recent decades. In many mountain regions, glacier recession has been accompanied by the development of proglacial lakes, which can pose a glacial lake outburst flood ( GLOF) hazard. However, no studies have assessed the development of such lakes in Bolivia despite recent GLOF incidents here. Our mapping from satellite imagery reveals an overall areal shrinkage of 228 : 1 +/- 22 : 8 km(2) ( 43.1 %) across the Bolivian Cordillera Oriental between 1986 and 2014. Shrinkage was greatest in the Tres Cruces region ( 47.3 %), followed by the Cordillera Apolobamba ( 43.1 %) and Cordillera Real ( 41.9 %). A growing number of proglacial lakes have developed as glaciers have receded, in accordance with trends in most other deglaciating mountain ranges, although the number of ice-contact lakes has decreased. The reasons for this are unclear, but the pattern of lake change has varied significantly throughout the study period, suggesting that monitoring of future lake development is required as ice continues to recede. Ultimately, we use our 2014 database of proglacial lakes to assess GLOF risk across the Bolivian Andes. We identify 25 lakes that pose a potential GLOF threat to downstream communities and infrastructure. We suggest that further studies of potential GLOF impacts are urgently required.