Subjects: Geosciences >> Hydrology submitted time 2023-03-14 Cooperative journals: 《干旱区地理》
Abstract： In arid areas，snowmelt is the main source of water resource formation. Therefore, the formation, transformation and utilization of snow resources are important research topics on the development and utilization of water resources in Xinjiang, China. Further, hydrological model is a key to determine the formation and transformation of water resources. This study uses the field experimental area of Tianshan Snow Station, Chinese Academy of Sciences, as the experimental area. The meteorological data and snowmelt amount were adopted as the independent and dependent variables. A snowmelt model based on temperature change is studied, and a singlefactor simple model is calibrated and validated. Simultaneously, the variation law of snowmelt in the experimental area for many years and the response process of snowmelt to temperature are analyzed. The results indicate that snowmelt still occurs in winter in certain low- temperature ranges. In the study area of Tianshan Mountains, the critical value of daily average temperature of snowmelt is approximately -7 ℃. When the temperature is lower than -7 ℃, snowmelt is basically suspended, reflecting the characteristics of snowmelt in arid areas. In terms of the model, a single factor simple snowmelt model based on temperature exhibits good performance in simulating snowmelt in mountainous areas. During the calibration period (2016—2020), the correlation parameters of Bias, MAE, RMSE, NSE and R2 between the observed and simulated snowmelt values were -0.037, 0.367, 0.482, 0.870, and 0.876 respectively. The values of validation period were -0.210, 0.292, 0.577, 0.845, and 0.811, respectively. The simulation results and correlation coefficients during the validation period indicate that the simulated value of the model has good consistency with the measured value. The advantage is that the amount of snowmelt in the basin can be estimated through the available meteorological data. The results provide a relatively simple algorithm for snowmelt calculation in arid areas and a simple and effective snowmelt submodule for a hydrological model. This study has an important reference value for understanding the change law of snowmelt and the simulation and prediction of snowmelt runoff in subsequent studies
Subjects: Geosciences >> Atmospheric Sciences submitted time 2021-08-01 Cooperative journals: 《干旱区地理》
Abstract： 近年来，随着气候变化，伊犁河谷积雪消融加快，极端水文事件的频度和强度也在加大。 通过利用中国科学院天山积雪站附近小流域的土壤水热和积雪融雪观测数据，对研究区积雪消融 规律、冻土水热变化特征及其对气温和融雪量的响应进行了分析。结果表明：在冻土融解阶段，土 壤温度的变化依赖大气温度的变化，而土壤水分受融雪量和气温的影响较大，高度相关。表层土 壤含水率的变幅最大，而深层土壤水分值较稳定，土壤水热的季节性变化自秋-冬-春大致呈现“下 降-平稳-上升”的趋势。在冻土层上边界，土壤含水率随着累积融雪量的增加而增加并达到饱和 值，而冻土层下边界（40 cm 深度）土壤水分保持非饱和稳定状态。在山区，降雪量是水资源形成的 主要来源。融雪量与大气温度的相关性显著（系数为 0.785），融雪量对水资源形成的贡献率为 40%左右。研究冻土水热对融雪和气温的响应过程，对于新疆水资源形成机理、转化利用以及洪水 预报具有重要的参考价值。
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2019-09-10 Cooperative journals: 《干旱区研究》
Abstract： 利用西天山阿热都拜小流域积雪、融雪和气象观测场2017—2018年每30 min的同步降雪、融雪和气温观测数据，对全年积雪期较短时间尺度上的融雪动态过程及其与气温的关系进行了对比分析。结果表明：山区降雪表现为“先升后降”的总体特征。稳定积雪期集中在2017年12月27日至2018年3月8日，最大降雪速率高达9.6 mm·h-1（雪水当量值，转化成新鲜雪深值为96.5 mm·h-1）。山区融雪过程的变化规律与降雪变化正好相反，呈现出“先降后升”的变化特征。融雪变化分为3个阶段，第一阶段：随着气温的下降，融雪速率下降，融雪速率由3.24 mm·h-1逐渐下降至0 mm·h-1；第二阶段：当气温低于融雪的临界温度（-13.5~-12.0 ℃）时，不产生融雪；第三阶段：随着气温的回升，融雪速率从0 mm·h-1逐渐上升至3.87 mm·h-1。在全年融雪与气温的大数据关系中，融雪量与气温的相关性系数不是很显著，其相关性系数为0.708；在无降水干扰下，7 d平均同步融雪量与气温的相关性系数处于显著水平，Pearson相关性系数为0.907，R2=0.823；当进一步考虑滞后效应后，融雪量与气温的相关性系数提升至极显著的线性关系，相关性系数高达0.943，R2=0.889，均通过了0.01显著性水平的双尾检验。在西天山阿热都拜小流域融雪量的变化过程与气温的变化过程有着密切的相关性。这种融雪量对气温变化的响应关系及其分析方法，对于提高应对未来气候变化的能力和预防洪灾及水资源管理具有一定的参考价值。
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