Application of snowmelt runoff model(SRM) in mountainous watersheds:A review

The snowmelt runoff model （SRM） has been widely used in simulation and forecast of streamflow in snow-dominated mountainous basins around the world. This paper presents an overall review of worldwide applications of SRM in mountainous watersheds, particularly jn data-sparse watersheds of northwestern China. Issues related to proper selection of input climate variables and parameters, and determination of the snow cover area （SCA）using remote sensing data in snowmelt runoff modeling are discussed through extensive review of literature. Preliminary applications of SRM in northwestern China have shown that the model accuracies are relatively acceptable although most of the watersheds lack measured hydro-meteorological data. Future research could explore the feasibility of modeling snowmelt runoff in data-sparse mountainous watersheds in northwestern China by utilizing snow and glacier cover remote sensing data, geographic information system （GIS） tools, field measurements, and innovative ways of model parameterization.

Snowmelt runoff prediction under changing climate in the Himalayan cryosphere: A case of Gilgit River Basin

There are serious concerns of rise in temperatures over snowy and glacierized Himalayan region that may eventually affect future river flows of Indus river system. It is therefore necessary to predict snow and glacier melt runoff to manage future water resource of Upper Indus Basin(UIB). The snowmelt runoff model(SRM) coupled with MODIS remote sensing data was employed in this study to predict daily discharges of Gilgit River in the Karakoram Range. The SRM was calibrated successfully and then simulation was made over four years i.e. 2007, 2008, 2009 and 2010 achieving coefficient of model efficiency of 0.96, 0.86, 0.9 and 0.94 respectively. The scenarios of precipitation and mean temperature developed from regional climate model PRECIS were used in SRM model to predict future flows of Gilgit River. The increase of 3 C in mean annual temperature by the end of 21 th century may result in increase of 35-40% in Gilgit River flows. The expected increase in the surface runoff from the snow and glacier melt demands better water conservation and management for irrigation and hydel-power generation in the Indus basin in future.

Integration of aspect and slope in snowmelt runoff modeling in a mountain watershed

This study assessed the performances of the traditional temperature-index snowmelt runoff model(SRM) and an SRM model with a finer zonation based on aspect and slope(SRM + AS model) in a data-scarce mountain watershed in the Urumqi River Basin,in Northwest China.The proposed SRM + AS model was used to estimate the melt rate with the degree-day factor(DDF) through the division of watershed elevation zones based on aspect and slope.The simulation results of the SRM + AS model were compared with those of the traditional SRM model to identify the improvements of the SRM + AS model's performance with consideration of topographic features of the watershed.The results show that the performance of the SRM + AS model has improved slightly compared to that of the SRM model.The coefficients of determination increased from 0.73,0.69,and 0.79 with the SRM model to 0.76,0.76,and 0.81 with the SRM + AS model during the simulation and validation periods in 2005,2006,and 2007,respectively.The proposed SRM + AS model that considers aspect and slope can improve the accuracy of snowmelt runoff simulation compared to the traditional SRM model in mountain watersheds in arid regions by proper parameterization,careful input data selection,and data preparation.

SNOW COVER MONITORING BY REMOTE SENSING AND SNOWMELT RUNOFF CALCULATION IN THE UPPER HUANGHE RIVER BASIN

The upper Huanghe(Yellow) River basin is situated in the northeast of the Qinghai Xizang(Tibet)Plateau of China. The melt water from the snow cover is main water supply for the rivers in the region during springtime and other arid regions of the northwestern China, and the hydrological conditions of the rivers are directly controlled by the snowmelt water in spring. So snowmelt runoff forecast has importance for hydropower, flood prevention and water resources utilization. The application of remote sensing and Geographic Information System (GIS) techniques in snow cover monitoring and snowmelt runoff calculation in the upper Huanghe River basin are introduced amply in this paper. The key parameter-snow cover area can be computed by satellite images from multi platform, multi temporal and multi spectral. A cluster of snow cover data can be yielded by means of the classification filter method. Meanwhile GIS will provide relevant information for obtaining the parameters and also for zoning. According to the typical samples extracting snow covered mountainous region, the snowmelt runoff calculation models in the upper Huanghe River basin are presented and they are mentioned in detail also. The runoff snowmelt models based on the snow cover data from NOAA images and observation data of runoff, precipitation and air temperature have been satisfactorily used for predicting the inflow to the Longyangxia Reservoir , which is located at lower end of snow cover region and is one of the largest reservoirs on the upper Huanghe River, during late March to early June. The result shows that remote sensing techniques combined with the ground meteorological and hydrological observation is of great potential in snowmelt runoff forecasting for a large river basin. With the development of remote sensing technique and the progress of the interpretation method, the forecast accuracy of snowmelt runoff will be improved in the near future. Large scale extent and few stations are two objective reality situations in China, so they should be considered in simulation and forecast. Apart from dividing, the derivation of snow cover area from satellite images would decide the results of calculating runoff. Field investigation for selection of the learning samples of different snow patterns is basis for the classification.

Effect of climatic change on snowmelt runoffs in mountainous regions of inland rivers in Northwestern China

Climatic change has significant impacts on snow cover in mid-latitude mountainous re- gions, in the meantime, spatial and temporal changes of snow cover and snowmelt runoffs are con- sidered as sensitive indicators for climatic change. In this study, the upper Heihe Watershed in the Qilian Mountains was selected as a typical area affected by snow cover and snowmelt runoffs in northwestern China. The changes in air temperatures, precipitation, snowfall and spring snowmelt runoffs were analyzed for the period from 1956 to 2001. The results indicate that climatic warming was apparent, particularly in January and February, but precipitation just fluctuated without a clear trend. The possible changes of snowmelt runoffs in the upper Heihe watershed in response to a warming of 4℃ were simulated using Snowmelt Runoff Model (SRM) based on the degree-day factor algorithm. The results of the simulation indicate that a forward shifting of snow melting season, an increase in water flows in earlier melting season, and a decline in flows in later melting season would occur under a 4℃ warming scenario.

A test of Snowmelt Runoff Model(SRM)for the Gongnaisi River basin in the western Tianshan Mountains,China

The Snowmelt Runoff Model (SRM) is one of a very few models in the world today that requires remote sensing derived snow cover as model input. Owing to its simple data requirements and use of remote sensing to provide snow cover information, SRM is ideal for use in data sparse regions, particularly in remote and inaccessible high mountain watersheds. In order to verify the applicability of SRM in an environment of continental climate, a test of SRM is performed for the Gongnaisi River basin in the western Tianshan Mountains, the results show that two SRM average goodness-of-fit statistics for simulations, Nash-Sutcliff coefficient (R2) and volume difference (DV), are 0.87 and 0.90%, respectively. As compared with the application results over 80 basins in 25 different countries around the world, SRM performs well in the Gongnaisi River basin. The results also show that SRM can be a validated snowmelt runoff model capable of being applied in the western Tianshan Mountains. On the basis of snowmelt runoff simulation, together with a set of simplified hypothetical climate scenarios, SRM is also used to simulate the effects of climate change on snow cover and the consecutive snowmelt runoff. For a given hypothetical temperature increase of 4℃, the snow coverage and snowmelt season shift towards earlier dates, and the snowmelt runoff, as a result, is changed significantly at the same time. The simulation results show that the snow cover is sensitive to changes of climate, especially to the increase of temperature, the major effect of climate change will be a time shifting of snowmelt runoff to early spring months, resulting in a redistribution of seasonally runoff throughout the whole snowmelt season.

Preliminary studies on the ionic pulse of snowmelt runoff in the Urumqi River, Xinjiang, Northwest China

IONIC pulse of snowmelt and its runoff in seasonally snow-covered alpine catchments was de-fined by Johannessen et al. When a snowpack begins melting, the first meltwater drainingthrough the pack carries a large fraction of the soluble ions with it, an ionic pulse. 10％ of thefirst meltwater may drain 80％ of the soluble contents out of the snowpack within severalhours or days. In other words, an ionic pulse designates a peak in ionic concentration duringthe initial melting process of a snowpack. The peak has been proved by a plot test 10 times

基于三维激光扫描技术的冻结黑土细沟发育模拟

为探究融雪径流与冻结状态对黑土细沟网络发育的影响,该研究开展了冻结与非冻结处理黑土坡面的融雪径流模拟冲刷试验,利用三维激光扫描技术获取多次定时径流冲刷并直至侵蚀形态稳定的坡面点云,结合数字表面模型差异(digital surface model of difference,DoD)微地形变化监测方法与点云逆向工程,获取细沟网络发育过程的侵蚀面积、侵蚀体积、细沟长度和细沟密度等侵蚀参数。结果表明,冻结因素与温度变化对细沟网络发育过程与程度有重要影响:1)冻结处理的黑土坡面更容易发展出细沟网络,达到坡面侵蚀形态基本稳定后的侵蚀面积、侵蚀体积以及侵蚀细沟长度是非冻结处理黑土坡面的291%、557%和437%。2)冻结处理与非冻结处理沿坡面细沟截面形态变化差异明显。冻结坡面细沟交叉时宽深比RW/D快速减小,下切速度加快,随后宽度与深度呈比例稳定增加;非冻结坡面汇水处的R_(W/D)随冲刷次数增加而增大,侧蚀速度加快,其他截面R_(W/D)随着冲刷次数的增加而减小,下切速度加快。3)采用ArcGIS与点云逆向工程模型联合获取的冻结状态下细沟形态参数与发育过程DoD相对误差范围为-12.70%~4.42%,提取精度在95%以上。该联合方法在冻结土体条件下获取细沟参数具有较高精度,可作为土壤侵蚀参数高精度提取的一种手段。

东北黑土区融雪径流侵蚀力时空分布

[目的]融雪侵蚀是东北黑土区主要土壤侵蚀形式之一,是该区土地退化的重要作用力,融雪径流侵蚀力是计算融雪径流侵蚀量的关键因子,因此研究融雪径流侵蚀力具有重要意义。融雪径流侵蚀力主要受积雪深度、辐射强度及升温速率影响,其主要驱动力包括融雪速率和地表径流作用。[方法]通过计算近31年日均融雪径流侵蚀力,分析东北黑土区融雪径流侵蚀力时空分布特征,并利用地理探测器辨析各区域融雪径流侵蚀力的主要影响因子。[结果]3个黑土亚区1990—2020年日均融雪径流侵蚀力均呈现先增大后减小态势,近些年逐步趋于稳定,多年日均融雪径流侵蚀力为0.01(MJ·mm)/(hm ^(2)·h·a);空间上多年日均融雪径流侵蚀力在0~0.21(MJ·mm)/(hm ^(2)·h·a)范围内,基本呈现中间小、四周大规律。融雪径流侵蚀力影响因子空间上表现为积雪深度北部大、南部小,太阳辐射强度呈现由西向东递减,升温速率值从北部向南部递减。通过地探测器辨析融雪径流侵蚀力影响因子作用强弱发现,升温速率对蒙东黑土亚区作用最强,而积雪深度对松嫩黑土亚区及三江黑土亚区作用最强。[结论]通过分析1990—2020年东北黑土区融雪径流侵蚀力时空特征及其影响因子,对于深化研究区融雪径流侵蚀特征及融雪侵蚀防控具有一定的理论和实践意义。

分布式融雪径流模型研究进展

融雪径流在寒区、干旱区对当地的水资源起着十分重要的作用,但融雪同样也会带来融雪性洪水、山体滑坡等自然灾害,因此对融雪径流的模拟一直是寒旱区的重要热点,针对近些年来融雪径流模拟研究的发展趋势,介绍融雪径流模拟的主要类型,一类是基于能量平衡的物理模型,另一类是基于气温指标的度日模型。重点阐述分布式融雪径流模型的应用情况及其进展,并对分布式融雪径流模型进行讨论与展望。

Application of Snow Melt Runoff Model in a Mountainous Basin of Iran

Simulation and modeling the stream flow provide major data while it is a challenge in mountainous basins with regard to the important role of snowmelt runoff as well as the data scarcity in these places. The main purpose of this paper is to examine the capability of an integrated application of remote sensing data and Snowmelt Runoff Model (SRM) to simulate scheme of daily stream flow in the snow-dominated catchment, located in the North-East region of Iran. The main parameters of the model are Snow Cover Area (SCA), temperature and participation. Regarding to the lack of measured data, the input variable and parameters of the model are extracted or estimated based on accessible maps, satellite data and available meteorological and hydrological stations. The changes of snow-cover, as spatial-temporal data, which are the most effective variable in performance of SRM, are obtained from the Moderate Resolution Imaging Spectroradiometer (MODIS) eight-day composite snow cover images. The evaluation of the model application efficiency was tested by the coefficient of determination and the volume difference, which are 0.85% and -4.6% respectively. The result depicts the relative capability of SRM though it is evident that the more accurate the estimation of model parameters, the more efficient simulation results can be obtained.

Snowmelt modeling using two melt-rate models in the Urumqi River watershed, Xinjiang Uyghur Autonomous Region, China

In this paper,the performance of the classic snowmelt runoff model(SRM)is evaluated in a daily discharge simulation with two different melt models,the empirical temperature-index melt model and the energy-based radiation melt model,through a case study from the data-sparse mountainous watershed of the Urumqi River basin in Xinjiang Uyghur Autonomous Region of China.The classic SRM,which uses the empirical temperature-index method,and a radiation-based SRM,incorporating shortwave solar radiation and snow albedo,were developed to simulate daily runoff for the spring and summer snowmelt seasons from 2005 to 2012,respectively.Daily meteorological and hydrological data were collected from three stations located in the watershed.Snow cover area(SCA)was extracted from satellite images.Solar radiation inputs were estimated based on a digital elevation model(DEM).The results showed that the overall accuracy of the classic SRM and radiation-based SRM for simulating snowmeltdischarge was relatively high.The classic SRM outperformed the radiation-based SRM due to the robust performance of the temperature-index model in the watershed snowmelt computation.No significant improvement was achieved by employing solar radiation and snow albedo in the snowmelt runoff simulation due to the inclusion of solar radiation as a temperature-dependent energy source and the local pattern of snowmelt behavior throughout the melting season.Our results suggest that the classic SRM simulates daily runoff with favorable accuracy and that the performance of the radiation-based SRM needs to be further improved by more ground-measured data for snowmelt energy input.

Application of hydrological models in a snowmelt region of Aksu River Basin

This study simulated and predicted the runoff of the Aksu River Basin, a typical river basin supplied by snowmelt in an arid mountain region, with a limited data set and few hydrological and meteorological stations. Two hydrological models, the snowmelt-runoff model （SRM） and the Danish NedbФr-AfstrФmnings rainfall-runoff model （NAM）, were used to simulate daily discharge processes in the Aksu River Basin. This study used the snow-covered area from MODIS remote sensing data as the SRM input. With the help of ArcGIS software, this study successfully derived the digital drainage network and elevation zones of the basin from digital elevation data. The simulation results showed that the SRM based on MODIS data was more accurate than NAM. This demonstrates that the application of remote sensing data to hydrological snowmelt models is a feasible and effective approach to runoff simulation and prediction in arid unguaged basins where snowmelt is a major runoff factor.

Response of runoff and its components to climate change in the Manas River of the Tian Shan Mountains

A warming-wetting climate trend has led to increased runoff in most watersheds in the Tian Shan Mountains over the past few decades.However,it remains unclear how runoff components,that is,rainfall runoff(Rrain),snowmelt runoff(Rsnow),and glacier meltwater(Rglacier),responded to historical climate change and how they will evolve under future climate change scenarios.Here,we used a modified Hydrologiska Byrans Vattenbalansavdelning(HBV)model and a detrending method to quantify the impact of precipitation and temperature changes on runoff components in the largest river(Manas River)on the northern slope of the Tian Shan Mountains from 1982 to 2015.A multivariate calibration strategy,including snow cover,glacier area,and runoff was implemented to constrain model parameters associated with runoff components.The downscaled outputs of 12 general circulation models(GCMs)from the Sixth Coupled Model Intercomparison Project(CMIP6)were also used to force the modified HBV model to project the response of runoff and its components to future(2016-2100)climate change under three common socio-economic pathways(SSP126,SSP245,and SSP585).The results indicate that Rrain dominates mean annual runoff with a proportion of 42%,followed by Rsnow(37%)and Rglacier(21%).In terms of inter-annual variation,Rrain and Rsnow show increasing trends(0.93(p<0.05)and 0.31(p>0.05)mm per year),while Rglacier exhibits an insignificant(p>0.05)decreasing trend(-0.12 mm per year),leading to an increasing trend in total runoff(1.12 mm per year,p>0.05).The attribution analysis indicates that changes in precipitation and temperature contribute 8.16 and 10.37 mm,respectively,to the increase in runoff at the mean annual scale.Climate wetting(increased precipitation)increases Rrain(5.03 mm)and Rsnow(3.19 mm)but has a limited effect on Rglacier(-0.06 mm),while warming increases Rrain(10.69 mm)and Rglacier(5.79 mm)but decreases Rsnow(-6.12 mm).The negative effect of glacier shrinkage on Rglacier has outweighed the positive effect of warming on Rglaciers resulting in the tipping point(peak water)for Rglacier having passed.Runoff projections indicate that future decreases in Rglacier and Rsnow could be offset by increases in Rrain due to increased precipitation projections,reducing the risk of shortages of available water resources.However,management authorities still need to develop adequate adaptation strategies to cope with the continuing decline in Rgacier in the future,considering the large inter-annual fluctuations and high uncertainty in precipitation projection.

东北寒区SWAT模型融雪径流空间异质性参数率定方法及应用——以白山流域为例

融雪水是东北地区春季径流的重要来源,融雪径流过程的可靠模拟及预报可为科学管理和调度春汛期水资源提供参考。东北寒区年度内存在融雪径流和降雨径流两种产流模式,流域物理空间属性差异对融雪径流产流模式影响显著,为了解决东北寒区融雪径流空间异质性问题、提高SWAT模型模拟及预报精度,提出对SWAT模型采用单站点和多站点联合参数率定的策略。首先,利用白山水库入库流量进行单站初步参数率定,进而,采用多站点对融雪径流参数进行率定,并将该参数移植到单站初步率定参数集。结果表明:单站初步参数率定后模拟得到年度(1—12月)、夏季汛期(6—9月)、春季融雪期(3—5月)验证期月尺度确定系数(R^(2))分别为0.76、0.74和0.58,日尺度R^(2)分别为0.71、0.75和0.51;单站和多站点联合参数率定后模拟得到年度、夏季汛期、春季融雪期验证期月尺度R^(2)分别为0.80、0.74和0.79,日尺度R^(2)分别为0.74、0.78和0.61。在月尺度和日尺度上,单站和多站点联合参数率定较单站参数率定后春季融雪期的模拟精度分别提高了20%和10%。

HBV模型在玛纳斯河流域的适用性

新疆天山北坡山区流域水文气象资料稀缺,融雪径流模拟比较困难。为研究HBV模型在新疆天山北坡玛纳斯河流域径流模拟的适用性,通过分析流域积雪覆盖率与径流的相关性,并基于中国地面降水与气温日值0.5°×0.5°格点数据集,经空间插值得到研究区多年平均降水和气温的空间分布,运用HBV模型模拟了玛纳斯河流域2000—2013年日尺度和月尺度径流过程,与SRM的模拟效果进行对比分析。结果表明:①多年月平均积雪覆盖率与多年月平均流量呈负相关,相关系数R^(2)=0.67,流域内积雪融水对径流的补给作用明显;②数据集经空间插值得到研究区多年平均降水和气温的空间分布能基本反映流域的垂直气候差异性,数据集可作为玛纳斯河流域缺乏气象资料的高山区径流模拟的输入数据;③HBV模型与SRM在玛纳斯河流域日尺度和月尺度的径流模拟效果评价等级均为良好,且HBV模型对洪峰流量模拟效果更好,整体的模拟值与实测值偏差更小,HBV模型在玛纳斯河流域具有较好的适用性。

西北山区流域融雪水资源“四预”应用系统技术研究

我国西北山区流域融雪性径流是当地宝贵水资源,为提高融雪水资源综合管理业务工作效率,就具有融雪径流预报、来水极值预警、来水情势预演模拟分析、预案查询等“四预”功能的应用系统相关技术开展研究。分析西北山区流域管理机构和水库管理部门实际工作需要,提出系统功能需求,明确设计原则要求,结合最新信息化技术应用分析,提出采用主计算控制循环模式的系统处理过程控制形式,将人机交互界面设计为基于左右屏幕互动的交互式双屏显示方式,切实强化系统功能、性能等对业务工作实际需要的反映和对接,为开发实现良好的用户应用系统打下坚实基础。

气候变化对中国西北地区山区融雪径流的影响

选择祁连山黑河流域作为中国西北地区山区积雪流域的典型代表 ,分析了 195 6— 1995年 40a以来气候、积雪变化的状况和特点以及春季融雪径流的波动趋势 .利用融雪径流模型 (SnowmeltRunoffModel SRM)和卫星遥感数据模拟气温上升框架下的融雪径流变化情势 .结果表明 :中国西北地区山区的气候变化主要表现在年平均气温的缓慢上升而降水基本平稳 ,年内气温的上升幅度以 12月份比较强烈 ,而 36月融雪期的气温并没有大的变化 ,导致融雪期在时间尺度上的扩大 ,融雪径流呈慢增加趋势且受径流周期变化控制 。

SRM融雪径流模型在长江源区冬克玛底河流域的应用

冬克玛底河流域作为青藏高原腹地长江源区典型代表性高寒山区流域,有较大面积的冰川、积雪存在。本文以冬克玛底河流域2005年5￣10月的实测水文、气象资料为基础,运用SRM融雪径流模型对不同分带数对融雪径流模拟效果的影响和不同测站气温分别作为气温驱动变量对融雪径流模拟效果的影响分别进行了模拟试验。结果表明:不同分带会对SRM模型融雪径流量模拟产生一定的影响;而不同的气温作为驱动变量对模拟的效果影响很大,这表明SRM模型对气温驱动变量非常敏感。同样根据流域内径流与气温降水的相关分析看到日径流量与气温相关性较好,线性相关系数最好达到0.72,而径流与降水线性相关系数为0.20。根据以上模拟实验和相关分析选择合适的分带和具有代表性的站点气温,SRM模型模拟的两个优度指标最好可达到Nash-Sutcliffe系数(R2)=0.83和体积差(Dv)=0.95%。考虑到SRM模型对气温的敏感性,利用最终选择的模拟方案并结合气温升高1oC气候情景假设来考虑气温、降水和径流之间的关系。模拟结果表明:气温升高1oC后,(1)模拟时期内的径流总量由原来模拟的25.5×106m3增加到33×106m3;(2)冰川物质平衡线从原来的5600上升到5750米,冰川消融区从5.8km2增大到13.5km2,冰川消融量增加,对径流量的贡献明显增大。(3)气温的升高加速积雪融化并改变降水形态是径流在5￣6月变大的主导因素。7￣10月份的径流变大则主要是由于冰川消融。

SRM融雪径流模型在乌鲁木齐河源区的应用研究

乌鲁木齐河源区发育现代冰川7条,冰川面积5.6 km2,并有大范围的积雪,冰雪消融期融雪径流对乌鲁木齐河贡献显著。应用SRM(snowmelt runoff model)融雪径流模型来探讨乌鲁木齐河源区融雪期径流情况,利用度日方法,由流域本身特征及参变量获取方法的深入分析来率定模型参数,应用模拟指标Nash-Sutcliffe系数R2=0.702和积差Dv=6.81%来评价模型表现,研究发现:(1)气温、降水作为该模型的直接驱动变量对模型的模拟较为敏感。尝试对乌乌鲁木齐河源区的气温、降水数据进行IDW插值并进行修正,使得模型模拟精度提高,对模型变量的输入精度问题上提供了新的思路;(2)不同高度带上积雪的度日因子并不是稳定的,而度日因子的选取与调整对模型也非常重要;(3)模型本身的局限性也导致模拟精度的降低。结果表明SRM模型可在乌鲁木齐河流域推广应用,这必将对认识和利用乌鲁木齐河流域冰雪水资源具有重要意义。