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Calibration of a Rainfall-Runoff Model to Estimate Monthly Stream Flow in an Ungauged Catchment  [PDF]
Shahrbanou Firouzi, Mohamad B. Sharifi
Computational Water, Energy, and Environmental Engineering (CWEEE) , 2015, DOI: 10.4236/cweee.2015.44006
Abstract: Simulation of runoff in ungauged catchments has always been a challenging issue, receiving significant attention more importantly in practical applications. This study aims at calibration of an Artificial Neural Network (ANN) model which is capable to apply in an ungauged basin. The methodology is applied to two sub-catchments located in the Northern East of Iran. To examine the effect of physical characteristics of the catchment on the capability of the model generalization, it is attempted to synthesize effective parameters using empirical methods of runoff estimation. Firstly, the model was designed for a pilot sub-catchment and the statistical comparison between simulated runoff, and target depicted the capability of ANN to accurately estimate runoff over a catchment. Then, the calibrated model was generalized to another sub-catchment assumed as an ungauged basin while there are runoff data to compare the result. The result showed that the designed model is relatively capable to estimate monthly runoff for a homogenous ungauged catchment. The method presented in this study in addition to adding effective spatial parameters in simulation runoff and calibration of model by using empirical methods and the integration of any useful accessible data, examines the adaptability of model to an ungauged catchment.
Modelling monthly runoff generation processes following land use changes: groundwater–surface runoff interactions  [PDF]
M. Bari,K. R. J. Smettem
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 2004,
Abstract: A conceptual water balance model is presented to represent changes in monthly water balance following land use changes. Monthly rainfall–runoff, groundwater and soil moisture data from four experimental catchments in Western Australia have been analysed. Two of these catchments, 'Ernies' (control, fully forested) and 'Lemon' (54% cleared) are in a zone of mean annual rainfall of 725 mm, while 'Salmon' (control, fully forested) and 'Wights' (100% cleared) are in a zone with mean annual rainfall of 1125 mm. At the Salmon forested control catchment, streamflow comprises surface runoff, base flow and interflow components. In the Wights catchment, cleared of native forest for pasture development, all three components increased, groundwater levels rose significantly and stream zone saturated area increased from 1% to 15% of the catchment area. It took seven years after clearing for the rainfall–runoff generation process to stabilise in 1984. At the Ernies forested control catchment, the permanent groundwater system is 20 m below the stream bed and so does not contribute to streamflow. Following partial clearing of forest in the Lemon catchment, groundwater rose steadily and reached the stream bed by 1987. The streamflow increased in two phases: (i) immediately after clearing due to reduced evapotranspiration, and (ii) through an increase in the groundwater-induced stream zone saturated area after 1987. After analysing all the data available, a conceptual monthly model was created, comprising four inter-connecting stores: (i) an upper zone unsaturated store, (ii) a transient stream zone store, (ii) a lower zone unsaturated store and (iv) a saturated groundwater store. Data such as rooting depth, Leaf Area Index, soil porosity, profile thickness, depth to groundwater, stream length and surface slope were incorporated into the model as a priori defined attributes. The catchment average values for different stores were determined through matching observed and predicted monthly hydrographs. The observed and predicted monthly runoff for all catchments matched well with coefficients of determination (R2) ranging from 0.68 to 0.87. Predictions were relatively poor for: (i) the Ernies catchment (lowest rainfall, forested), and (ii) months with very high flows. Overall, the predicted mean annual streamflow was within ±8% of the observed values. Keywords: monthly streamflow, land use change, conceptual model, data-based approach, groundwater
A Study of Rainfall-Runoff Response in a Catchment Using TOPMODEL
SUN Shufen,DENG Huiping,
SUN Shufen
,DENG Huiping

大气科学进展 , 2004,
Abstract: The simplicity of Topography-based hydrological model (TOPMODEL),as a way of reflecting the topographic controls on soil water storage and runoff generation,has become more attractive and morepopular for land surface process study since digital elevation models (DEMs) have become widely available.In this paper,the effect of the topography index on soil water storage distribution,which is the key to TOPMODEL,is explained.Then a simple water cycle model for estimating other components of the surface water cycle is developed,which is implemented into the TOPMODEL to integrate the water cycle of the catchment.Using the output of a DEM from 100 m × 100 m resolution data and a single flow direction algorithm,the index distribution function is calculated for a catchment (around 2500 km2 )in the upper reaches of the Yangtze River under different channel initiation thresholds.Finally,the daily and monthly rainfall-runoff response from 1960 to 1987 for the catchment is simulated with the TOPMODEL coupled with the simple water cycle model.
Analysis on the Characteristics of Annual Runoff in Hotan Catchment
新疆和田河流域河川径流时序特征分析

WU Yi,CHENG Wei-ming,REN Li-liang,ZHANG Yi-chi,ZHANG Xue-ren,
吴益
,程维明,任立良,张一驰,张学仁

自然资源学报 , 2006,
Abstract: The runoff of a catchment is affected comprehensively by human activities and natural conditions such as soil,vegetation,climate,etc.Therefore streamflow represents the characteristics of determinacy as well as stochasticism.Researches on runoff characteristics are beneficial for the sustainable utilization of water resources,water conservancy planning and agricultural develop-ment. The study area of this paper is Hotan catchment,which is located in the Tarim River Basin in southern Xinjiang,with an area of 48 870km2.The Hotan River is of great importance to ecosystem and society in Taklimakan Desert,because it is the only river that traverses the desert.The paper analyzed the intra-annual distribution and annual variation of runoff in the catchment according to observed data.Some indexes,including the coefficient of nonuniformity,the degree of concentration and the time of concentration,were used to analyze the intra-annual distribution of runoff;the methods of Kendall rank test and periodgram were used to analyze the trend and period of multi-annual runoff. The results show that due to the impacts of runoff-supplying sources,the intra-annual nonuniformity is very high,being more than 75% of the annual total runoff in summer.The coefficient of nonuniformity and the degree of concentration are much bigger than the normal,and the computed time of concentration is in accordance with the time of the observed maximum monthly runoff.The streamflow concentrated in some period of time could possibly arise the conflicts between water usage and supply,which will restrict the sustainable development of agricultural production and the socioeconomy.The Hotan River Basin is supplied by the glaciers and snow mountains,so the statistic of annual runoff Cv is small which indicates that the variation of annual runoff is weak.The annual precipitation,temperature and human activities exert impacts on the variation of runoff.The precipitation influences the runoff directly,in the past 40 years,the precipitation in the Hotan catchment presented an increasing trend.Under the background of global warming,the snow line on the mountains is hoisting and the glacier is shrinking.And with the development of agriculture,the irrigation water requirement is increasing constantly.Owning to the effect of these factors,the runoff in Hotan catchment presents a weak declining trend.The result of periodical analysis is that the annual runoff has no obvious periodicity.
A comparative analysis of projected impacts of climate change on river runoff from global and catchment-scale hydrological models
S. N. Gosling,R. G. Taylor,N. W. Arnell,M. C. Todd
Hydrology and Earth System Sciences Discussions , 2010, DOI: 10.5194/hessd-7-7191-2010
Abstract: We present a comparative analysis of projected impacts of climate change on river runoff from two types of distributed hydrological model, a global hydrological model (GHM) and catchment-scale hydrological models (CHM). Analyses are conducted for six catchments that are global in coverage and feature strong contrasts in spatial scale as well as climatic and developmental conditions. These include the Liard (Canada), Mekong (SE Asia), Okavango (SW Africa), Rio Grande (Brazil), Xiangxi (China) and Harper's Brook (UK). A single GHM (Mac-PDM.09) is applied to all catchments whilst different CHMs are applied for each catchment. The CHMs include SLURP v. 12.2 (Liard), SLURP v. 12.7 (Mekong), Pitman (Okavango), MGB-IPH (Rio Grande), AV-SWAT-X 2005 (Xiangxi) and Cat-PDM (Harper's Brook). Simulations of mean annual runoff, mean monthly runoff and high (Q5) and low (Q95) monthly runoff under baseline (1961–1990) and climate change scenarios are presented. We compare the simulated runoff response of each hydrological model to (1) prescribed increases in global-mean air temperature of 1.0, 2.0, 3.0, 4.0, 5.0 and 6.0 °C relative to baseline from the UKMO HadCM3 Global Climate Model (GCM) to explore response to different amounts of climate forcing, and (2) a prescribed increase in global-mean air temperature of 2.0 °C relative to baseline for seven GCMs to explore response to climate model structural uncertainty. We find that the differences in projected changes of mean annual runoff between the two types of hydrological model can be substantial for a given GCM, and they are generally larger for indicators of high and low monthly runoff. However, they are relatively small in comparison to the range of projections across the seven GCMs. Hence, for the six catchments and seven GCMs we considered, climate model structural uncertainty is greater than the uncertainty associated with the type of hydrological model applied. Moreover, shifts in the seasonal cycle of runoff with climate change are represented similarly by both hydrological models, although for some catchments the monthly timing of high and low flows differs. This implies that for studies that seek to quantify and assess the role of climate model uncertainty on catchment-scale runoff, it may be equally as feasible to apply a GHM as it is to apply a CHM, especially when climate modelling uncertainty across the range of available GCMs is as large as it currently is. Whilst the GHM is able to represent the broad climate change signal that is represented by the CHMs, we find however, that for some catchments there
A comparative analysis of projected impacts of climate change on river runoff from global and catchment-scale hydrological models
S. N. Gosling, R. G. Taylor, N. W. Arnell,M. C. Todd
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 2011,
Abstract: We present a comparative analysis of projected impacts of climate change on river runoff from two types of distributed hydrological model, a global hydrological model (GHM) and catchment-scale hydrological models (CHM). Analyses are conducted for six catchments that are global in coverage and feature strong contrasts in spatial scale as well as climatic and developmental conditions. These include the Liard (Canada), Mekong (SE Asia), Okavango (SW Africa), Rio Grande (Brazil), Xiangxi (China) and Harper's Brook (UK). A single GHM (Mac-PDM.09) is applied to all catchments whilst different CHMs are applied for each catchment. The CHMs include SLURP v. 12.2 (Liard), SLURP v. 12.7 (Mekong), Pitman (Okavango), MGB-IPH (Rio Grande), AV-SWAT-X 2005 (Xiangxi) and Cat-PDM (Harper's Brook). The CHMs typically simulate water resource impacts based on a more explicit representation of catchment water resources than that available from the GHM and the CHMs include river routing, whereas the GHM does not. Simulations of mean annual runoff, mean monthly runoff and high (Q5) and low (Q95) monthly runoff under baseline (1961–1990) and climate change scenarios are presented. We compare the simulated runoff response of each hydrological model to (1) prescribed increases in global-mean air temperature of 1.0, 2.0, 3.0, 4.0, 5.0 and 6.0 °C relative to baseline from the UKMO HadCM3 Global Climate Model (GCM) to explore response to different amounts of climate forcing, and (2) a prescribed increase in global-mean air temperature of 2.0 °C relative to baseline for seven GCMs to explore response to climate model structural uncertainty. We find that the differences in projected changes of mean annual runoff between the two types of hydrological model can be substantial for a given GCM (e.g. an absolute GHM-CHM difference in mean annual runoff percentage change for UKMO HadCM3 2 °C warming of up to 25%), and they are generally larger for indicators of high and low monthly runoff. However, they are relatively small in comparison to the range of projections across the seven GCMs. Hence, for the six catchments and seven GCMs we considered, climate model structural uncertainty is greater than the uncertainty associated with the type of hydrological model applied. Moreover, shifts in the seasonal cycle of runoff with climate change are represented similarly by both hydrological models, although for some catchments the monthly timing of high and low flows differs. This implies that for studies that seek to quantify and assess the role of climate model uncertainty on catchment-scale runoff, it may be equally as feasible to apply a GHM (Mac-PDM.09 here) as it is to apply a CHM, especially when climate modelling uncertainty across the range of available GCMs is as large as it currently is. Whilst the GHM is able to represent the broad climate change signal that is represented by the CHMs, we find however, that for some catchments there are differences between GHMs and CHMs in mean a
Evaluation of catchment contributing areas and storm runoff in flat terrain subject to urbanisation
O. V. Barron, D. Pollock,W. Dawes
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 2011,
Abstract: Contributing Catchment Area Analysis (CCAA) is a spatial analysis technique developed and used for estimation of the hydrological connectivity of relatively flat catchments. It allows accounting for the effect of relief depressions on the catchment rainfall-runoff relationship which is not commonly considered in hydrological modelling. Analysis of distributed runoff was based on USDA runoff curves numbers (USDA, 1986), which utilised the spatial information on land cover and soil types, while CCAA was further developed to define catchment area contributing to river discharge under individual rainfall events. The method was applied to the Southern River catchment, Western Australia, showing that contributing catchment area varied from less than 20% to more than 60% of total catchment area under different rainfall and soil moisture conditions. Such variability was attributed to a compensating effect of relief depressions. CCAA was further applied to analyse the impact of urbanisation on the catchment rainfall-runoff relationship. It was demonstrated that in addition to an increase in runoff coefficient, urbanisation leads to expansion in the catchment area contributing to the river flow. This effect was more evident for the most frequent rainfall events, when an increase in contributing area was responsible for a 30–100% rise in predicted catchment runoff.
Identifying runoff processes on the plot and catchment scale
P. Schmocker-Fackel, F. Naef,S. Scherrer
Hydrology and Earth System Sciences (HESS) & Discussions (HESSD) , 2007,
Abstract: Rainfall-runoff models that adequately represent the real hydrological processes and that do not have to be calibrated, are needed in hydrology. Such a model would require information about the runoff processes occurring in a catchment and their spatial distribution. Therefore, the aim of this article is (1) to develop a methodology that allows the delineation of dominant runoff processes (DRP) in the field and with a GIS, and (2) to illustrate how such a map can be used in rainfall-runoff modelling. Soil properties were assessed of 44 soil profiles in two Swiss catchments. On some profiles, sprinkling experiments were performed and soil-water levels measured. With these data, the dominant runoff processes (DRP) were determined using the Scherrer and Naef (2003) process decision scheme. At the same time, a simplified method was developed to make it possible to determine the DRP only on the basis of maps of the soil, topography and geology. In 67% of the soil profiles, the two methods indicated the same processes; in 24% with minor deviations. By transforming the simplified method into a set of rules that could be introduced into a GIS, the distributions of the different DRPs in two catchments could be delineated automatically so that maps of the dominant runoff processes could be produced. These maps agreed well with manually derived maps and field observations. Flood-runoff volumes could be quite accurately predicted on the basis of the rainfall measured and information on the water retention capacity contained in the DRP map. This illustrates the potential of the DRP maps for defining the infiltration parameters used in rainfall-runoff models.
Identifying runoff processes on the plot and catchment scale
P. Schmocker-Fackel,F. Naef,S. Scherrer
Hydrology and Earth System Sciences Discussions , 2006,
Abstract: Rainfall-runoff models that adequately represent the real hydrological processes and that do not have to be calibrated, are needed in hydrology. Such a model would require information about the runoff processes occurring in a catchment and their spatial distribution. Therefore, the aim of this article is (1) to develop a methodology that allows the delineation of dominant runoff processes (DRP) in the field and with a GIS, and (2) to illustrate how such a map can be used in rainfall-runoff modelling. Soil properties were assessed of 44 soil profiles in two Swiss catchments. On some profiles, sprinkling experiments were performed and soil-water levels measured. With these data, the dominant runoff processes (DRP) were determined using the Scherrer and Naef (2003) process decision scheme. At the same time, a simplified method was developed to make it possible to determine the DRP only on the basis of maps of the soil, topography and geology. In 67% of the soil profiles, the two methods indicated the same processes; in 24% with minor deviations. By transforming the simplified method into a set of rules that could be introduced into a GIS, the distributions of the different DRPs in two catchments could be delineated automatically so that maps of the dominant runoff processes could be produced. These maps agreed well with manually derived maps and field observations. Flood-runoff volumes could be quite accurately predicted on the basis of the rainfall measured and information on the water retention capacity contained in the DRP map. This illustrates the potential of the DRP maps for defining the infiltration parameters used in rainfall-runoff models.
Evaluation of catchment connectivity and storm runoff in flat terrain subject to urbanisation  [PDF]
O. V. Barron,D. W. Pollock,W. R. Dawes
Hydrology and Earth System Sciences Discussions , 2009,
Abstract: Contributing Catchment Area Analysis (CCAA) is a spatial analysis technique that allows estimation of the hydrological connectivity of relatively flat catchments and the effect of relief depressions on the catchment rainfall-runoff relationship for individual rainfall events. CCAA of the Southern River catchment, Western Australia, showed that catchment contributing area varied from less than 20% to more than 60% of total catchment area for various rainfall events. Such variability was attributed to a compensating effect of relief depressions. CCAA was further applied to analyse the impact of urbanisation on the catchment rainfall-runoff relationship. It was demonstrated that the change in land use resulted in much greater catchment volumetric runoff than expected simply as a result of the increase in proportion of impervious urban surfaces. As urbanisation leads to an increase in catchment hydrological connectivity, the catchment contributing area to the river flow also becomes greater. This effect was more evident for the most frequent rainfall events, when an increase in contributing area was responsible for a 30–100% increase in total volumetric runoff. The impact of urbanisation was greatest in sandy catchments, which were largely disconnected in the pre-development conditions.
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