Flow Analysis at the Snow Covered High Altitude Catchment via Distributed Energy Balance Modeling
Flow Analysis at the Snow Covered High Altitude Catchment via Distributed Energy Balance Modeling
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DOI：
10.1038/s41598-019-39446-1
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发表时间：
2019-03
影响因子：
4.6
通讯作者：
A. Shakoor;N. Ejaz
中科院分区：
文献类型：
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作者：
A. Shakoor;N. Ejaz
在高海拔冰川流域，基于能量收支的分布式模拟对于准确描述水文过程和量化流量是必不可少的。在这项研究中，积雪模型及其分布式版本Alpine3D在巴基斯坦首次应用于模拟高海拔冰川集水区的径流响应。基本目的是探讨这一建模系统的可行性及其在该区域的未来应用。最终结果表明，该模型在实测流量和模型流量之间取得了令人满意的效果，纳什-萨克利夫效率为0.54。然而，模拟的总流量与位于冰川口的湖泊的实测流量仅相差1.3倍。径流成分分析表明，研究区的径流状况受冰雪融化径流的影响较大，冰雪融化对径流的贡献率为53%，冰川融化的贡献率为38%。在冰川融化季节，由于风速分布不准确和输入气象数据存在偏差，模式效率较低。结论是，如果在类似于具有长期数据集的研究地点的集水区对模型进行优化，则该模型可以获得高性能。这项研究为高精度分布式能量平衡模型在整个喀喇昆仑和喜马拉雅地区的潜在应用奠定了坚实的基础，以了解如此崎岖的地形冰川丰富的山脉的融化动力学。
Energy budget-based distributed modeling at high-altitude glacio-nival watersheds is essential to accurately describe hydrological processes and quantify the flow rates. In this study, SNOWPACK model and its distributed version Alpine3D are applied for the first time in Pakistan to simulate the runoff response of a high altitude glaciated catchment. The basic aim was to explore the feasibility of this modeling system and its future applications in the region. Final results demonstrated satisfactory performance of the model between measured and modeled discharges with Nash-Sutcliff Efficiency of 0.54. However, total simulated flow volume differs only 1.3 times as compared to measured discharge of the lake, located at the glacier snout. Flow composition analysis revealed that the runoff regime of the study site is strongly influenced by the snow and glacier melt runoff representing 53% snowmelt and 38% glacier melt contribution. Low model efficiency has been observed during glacier melting season due to inaccurate wind speed distribution and biased input met-data. It is concluded that high performance of this model can be achieved if the model is optimized over the catchment similar to the study site provided with long term data sets. This study leaves a firm foundation for the potential application of a highly accurate distributed energy balance model in the entire Karakoram and Himalaya region to understand the melt dynamics of such a rugged terrain glacier rich mountains.