Evaluating Glacier Volume Changes since the Little Ice Age Maximum and Consequences for Stream Flow by Integrating Models of Glacier Flow and Hydrology in the Cordillera Blanca, Peruvian Andes
Evaluating Glacier Volume Changes since the Little Ice Age Maximum and Consequences for Stream Flow by Integrating Models of Glacier Flow and Hydrology in the Cordillera Blanca, Peruvian Andes
复制标题
通过整合秘鲁安第斯山脉布兰卡山脉的冰川流量和水文学模型，评估自小冰期最大以来的冰川体积变化以及对水流的影响
作者：
K. Huh;B. Mark;M. Baraer;Y. Ahn
基于小冰期（LIA）重建的体积变化来评估冰体积损失对水流的历史贡献，可以直接关系到对当前冰川快速损失时代的冰川水文学的理解，这对秘鲁安第斯山脉的科迪勒拉布兰卡的水资源产生了令人不安的影响。然而，要准确预测发展中区域安第斯社会的未来冰川融水可用性，需要对重建冰川体积的长期冰川融水进行更广泛的定量估算。通过对19世纪中期（最近最广泛的山地冰川扩张发生在公元1850年左右）在科迪勒拉布兰卡不同流域的LIA古冰川进行建模，我们可以通过气候控制变量和时间的可能组合来重建冰川体积及其变化。利用2011年先进星载热发射与反射辐射计（ASTER）全球数字高程模型第2版（GDEM V2）和2008年光探测与测距（LiDAR）数据，我们计算了小冰期和现代冰川表面百年尺度冰川体积变化的速率和幅度。模型模拟结果与实测地貌数据吻合较好，重建模拟的V-S比例尺误差在25%以内。此外，我们采用了最近证明的方法（Baraër， M. et al.）来计算融水对冰川化汇水径流的贡献。研究结果显示，在以往对同一山脉的研究中，从未出现过年平均流量和旱季平均流量的多个峰值。
Evaluating the historical contribution of the volume loss of ice to stream flow based on reconstructed volume changes through the Little Ice Age (LIA) can be directly related to the understanding of glacier-hydrology in the current epoch of rapid glacier loss that has disquieting implications for a water resource in the Cordillera Blanca in the Peruvian Andes. However, the accurate prediction of the future glacial meltwater availability for the developing regional Andean society needs more extensive quantitative estimation from long-term glacial meltwater of reconstructed glacial volume. Modeling the LIA paleoglaciers through the mid-19th century (with the most extensive recent period of mountain glacier expansion having occurred around 1850 AD) in different catchments of the Cordillera Blanca allows us to reconstruct glacier volume and its change from likely combinations of climatic control variables and time. We computed the rate and magnitude of centennial-scale glacier volume changes for glacier surfaces between the LIA and the modern era, as defined by 2011 Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Global Digital Elevation Model Version 2 (GDEM V2) and 2008 Light Detection and Range (LiDAR) data. The model simulation showed good agreement with the observed geomorphic data and the volume and surface area (V-S) scaling remained within the 25% error range in the reconstructed simulation. Also, we employed a recently demonstrated approach (Baraër, M. et al.) to calculate meltwater contribution to glacierized catchment runoff. The results revealed multiple peaks of both mean annual and dry season discharge that have never been shown in previous research on the same mountain range.