温升背景下山区积雪加速消融机理及其融雪洪水效应研究

积雪的广泛分布很大程度上影响着地表水量平衡和人类生产生活。气候变化对山区积雪的影响一直是积雪研究的关键科学问题。山区积雪水资源季节性存储特征使其在消融期大规模释放，近30年来山区增温显著导致年内积雪水文循环加剧，甚至形成洪水，威胁社会安全。然而，山区积雪空间异质性大，地面观测数据不足，积雪加速消融机理及灾害影响方面还未认识清楚。本项目拟选择北疆阿尔泰山为典型研究区，借助已有野外观测网络和遥感在缺资料山区的优势，结合成熟的基于能量平衡过程的寒区水文模型(GBEHM)，构建山区以积雪为主体的高时空分辨率分布式融雪洪峰模型。通过对历史时期融雪洪峰分析和模拟，揭示积雪加速消融过程的主要影响因素和机理；评估未来不同温升和CIMP6气候情景下，可能产生的融雪洪水效应。本研究可拓展对山区加速融雪过程、规律和机制的认识；为人类适应气候变化、制定应对政策提供基础支撑。

The distribution of snow cover greatly affects the water balance and human life. The influence of climate change on snow cover in mountainous areas has always been one of the key scientific issues in snow cover research. In the past 30 years, the temperature in mountain area has increased faster. The snow stored in the mountain area seasonally is released and significantly contributes to runoff in the melting season. The annual hydrological cycle of snow in the mountain area is intensifying, and it even forms floods, to threaten social security. However, due to the large spatial heterogeneity of snow in mountainous areas, in situ observation is very difficult. Due to the lack of ground observation data, there is little information available on the mechanism and flood impact of accelerated snow ablation. In our research, we will take the Altay Mountain in northern Xinjiang as a typical study area. Based on the data of ground observation network in Altay Mountain and remote sensing, combining with the well-developed cold region hydrological model (GBEHM)，to construct distributed snow hydrological model with high spatial and temporal resolution in alpine regions. Meanwhile, based on the analysis and simulation of snow accelerated ablation process in historical period, we expect to clarify the main influencing factors and mechanism of accelerated snow ablation in mountain area and to assess the possible snowmelt flood effect in future under climate warming (or CIMP6 scenarios). This research can expand our understanding of the mechanisms of rapid snowmelt events occurrence in mountainous areas, and can provide the basic support for human adaptation to climate change and the formulation of adaptation policies under global warming.