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1.
Method and Excel VBA Algorithm for Modeling Master Recession Curve Using Trigonometry Approach 
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下载免费PDF全文 A new method was developed and implemented into an Excel Visual Basic for Applications (VBAs) algorithm utilizing trigonometry laws in an innovative way to overlap recession segments of time series and create master recession curves (MRCs). Based on a trigonometry approach, the algorithm horizontally translates succeeding recession segments of time series, placing their vertex, that is, the highest recorded value of each recession segment, directly onto the appropriate connection line defined by measurement points of a preceding recession segment. The new method and algorithm continues the development of methods and algorithms for the generation of MRC, where the first published method was based on a multiple linear/nonlinear regression model approach (Posavec et al. 2006). The newly developed trigonometry‐based method was tested on real case study examples and compared with the previously published multiple linear/nonlinear regression model‐based method. The results show that in some cases, that is, for some time series, the trigonometry‐based method creates narrower overlaps of the recession segments, resulting in higher coefficients of determination R2, while in other cases the multiple linear/nonlinear regression model‐based method remains superior. The Excel VBA algorithm for modeling MRC using the trigonometry approach is implemented into a spreadsheet tool (MRCTools v3.0 written by and available from Kristijan Posavec, Zagreb, Croatia) containing the previously published VBA algorithms for MRC generation and separation. All algorithms within the MRCTools v3.0 are open access and available free of charge, supporting the idea of running science on available, open, and free of charge software. 相似文献
2.
The fully automated objective-based method for master recession curve (MRC) separation was developed by using Microsoft Excel spreadsheet and Visual Basic for Applications (VBA) code. The core of the program code is used to construct an MRC by using the adapted matching strip method (Posavec et al. 2006). Criteria for separating the MRC into two or three segments are determined from the flow-duration curve and are represented as the probable range of percent of flow rate duration. Successive separations are performed automatically on two and three MRCs using sets of percent of flow rate duration from selected ranges and an optimal separation model scenario, having the highest average coefficient of determination R2, is selected as the most appropriate one. The resulting separated master recession curves are presented graphically, whereas the statistics are presented numerically, all in separate sheets. Examples of field data obtained from two springs in Istria, Croatia, are used to illustrate its application. The freely available Excel spreadsheet and VBA program ensures the ease of use and applicability for larger data sets. 相似文献
3.
Kun‐xia Yu Lars Gottschalk Xiang Zhang Peng Li Zhanbin Li Lihua Xiong Qian Sun 《水文研究》2018,32(12):1844-1857
An approach for nonstationary low‐flow frequency analysis is developed and demonstrated on a dataset from the rivers on the Loess Plateau of China. Nonstationary low‐flow frequency analysis has drawn significant attention in recent years by establishing relationships between low‐flow series and explanatory variables series, but few studies have tested whether the time‐varying moments of low flow can be fully described by the time‐varying moments of the explanatory variables. In this research, the low‐flow distributions are analytically derived from the 2 basic explanatory variables—the recession duration and the recession coefficient—with the assumption that the recession duration and recession coefficient variables follow exponential and gamma distributions, respectively; the derived low‐flow distributions are applied to test whether the time‐varying moments of explanatory variables can explain the nonstationarities found in the low‐flow variable. The effects of ecosystem construction measures, that is, check dam, terrace, forest, and grassland, on the recession duration and recession coefficient are further discussed. Daily flow series from 11 hydrological stations from the Loess Plateau are used and processed with a moving average technique. Low‐flow data are extracted following the pit under threshold approach. Six of the 11 low‐flow series show significant nonstationarities at the 5% significance level, and the trend curves of the moments of low flow are in close agreement with the curves estimated from the derived distribution with time‐dependent moments of the recession duration and time‐constant moments of the recession coefficient. It is indicated that the nonstationarity in the low‐flow distribution results from the nonstationarity in the recession duration in all 6 cases, and the increase in the recession duration is resulted from large‐scale ecosystem constructions rather than climate change. The large‐scale ecosystem constructions are found to have more influence on the decrease in streamflow than on the increase in watershed storage, thus resulting in the reduction of low flow. A high return period for the initial fixed design value decreases dramatically with an increasing recession duration. 相似文献
4.
Virgilio Fiorotto 《水文科学杂志》2013,58(5):966-975
Abstract The analysis of drought discharge is of utmost relevance in the design of water intake structures, management of water resources, and in coping with environmental issues. In this context, the master recession curve represents a tool in hydrological analysis, giving integrated information on long period drought flow rates. In this paper, a technique is developed for deriving a master recession curve directly from daily discharge series that takes into account the high variability in the behaviour of individual recession segments. The statistical framework developed allows us to explicitly represent uncertainty, and hence a novel interpretation of the master recession curve is derived. The method is successfully applied to three important Italian basins draining the southern slopes of the eastern Alps. Citation Fiorotto, V. and Caroni, E., 2013. A new approach to master recession curve analysis. Hydrological Sciences Journal, 58 (5), 966–975. 相似文献
5.
ABSTRACTThis study assesses the sensitivity to model fitting methods and segment selection of the estimated parameters A and B of the model dQ/dt = ?AQB for individual events. We investigated about 750 recession events observed at 25 US Geological Survey gauges in the Iowa and Cedar river basins in the United States, with drainage areas ranging from 7 to 17 000 km2. The parameters of these recession events were estimated using three commonly adopted methods and recession segments with different extraction criteria. The results showed that the variations of the parameter estimates for the same recession event were comparable to the variations of parameters between different events due to using different model fitting methods and recession segments. This raises cautions for comparative analysis of individual recessions. The result also implies that the nonlinear direct fitting method is the most robust among the three model fitting methods compared.
EDITOR Z.W. Kundzewicz ASSOCIATE EDITOR T. Okruszko 相似文献
6.
Sixteen small catchments in the Maroondah region of Victoria, Australia were analysed using rainfall, temperature and streamflow time series with a rainfall–runoff model whose parameters efficiently characterize the hydrological response of a catchment. A set of catchment attributes for each of these catchments was then compared with the associated set of hydrological response characteristics of the catchments as estimated by the model. The time constant governing quickflow recession of streamflow (τq) was related to the drainage network and catchment area. The time constant governing slowflow recession of streamflow (τs) was related to the slope and shape of the catchment. The parameter governing evapotranspirative losses ( f ) was related to catchment gradient and vegetative water use. Forestry activities in the catchments changed evapotranspirative losses and thus total volume of streamflow, but did not affect the rate of streamflow recession. 相似文献
7.
Data obtained along various segments of the Mid-Ocean Ridge (MOR) are used to construct an idealized model for crustal accretion. The model seeks to predict the topographic, volcanic, tectonic, and hydrothermal characteristics of any given spreading segment of the MOR as a function of distance away from the bounding transform faults. This model is based on a series of detailed mapping efforts carried out on segments of the MOR having a broad range of spreading rates between 2 and 16 cm/yr. This paper includes the results of the French SEARISE program carried out during the summer of 1980 aboard the N/O “Jean Charcot” and two American cruises conducted in 1981 aboard the R/V “Melville”. 相似文献
8.
《水文科学杂志》2013,58(6)
Abstract A two-parameter gamma distribution for synthetic unit hydrographs (SUH) is compared with the Clark's and Espey's SUHs. A critical comparison of Clark's and gamma UHs, in terms of recession characteristics and time–area curve, is presented. It is observed that, in principle, a gamma UH can represent the hydrograph recession better than the Clark's UH does. Selection of a time–area curve is needed for obtaining the Clark's UH. The main problem in developing a SUH using the Clark's method is identified as the non-availability of a parametric form of the time–area curve. The time–area curve as represented in the hydrological model HEC-1, for the use in Clark's method, is found inadequate and unjustified. Gamma UHs obtained without optimization, for several examples, are found consistent with their physical meanings and better than the respective Clark's UH in reproducing runoff obtained with optimization. The parameters of Clark's UH (i.e. time of concentration and recession constant), as optimized through the HEC-1 program, are found inconsistent with their empirical origins and physical meanings; these lose their physical meaning and serve only as fitting parameters. This is due to the inappropriate time–area curve. A gamma UH has also the advantage of having fewer parameters than Clark's UH, which makes it more identifiable while still maintaining a connection with the physics of the problem. Espey's SUH for urban watersheds is transmuted to a gamma distribution using the empirical equations for the peak and time to peak of the UH. A numerical UH for a gauged catchment, generally obtained through linear programming or a least-squares approach, can be easily transmuted to a gamma UH and, hence, can be given a conceptual interpretation. Thus, these can also be used for developing a SUH. 相似文献
9.
Update on the use of the RORA program for recharge estimation 总被引：5，自引：2，他引：3
Rutledge AT 《Ground water》2007,45(3):374-382
10.
Tomas Vitvar Douglas A. Burns Gregory B. Lawrence Jeffrey J. McDonnell David M. Wolock 《水文研究》2002,16(9):1871-1877
A method for estimation of mean baseflow residence time in watersheds from hydrograph runoff recession characteristics was developed. Runoff recession characteristics were computed for the period 1993–96 in the 2 km2 Winnisook watershed, Catskill Mountains, southeastern New York, and were used to derive mean values of subsurface hydraulic conductivity and the storage coefficient. These values were then used to estimate the mean baseflow residence time from an expression of the soil contact time, based on watershed soil and topographic characteristics. For comparison, mean baseflow residence times were calculated for the same period of time through the traditional convolution integral approach, which relates rainfall δ18O to δ18O values in streamflow. Our computed mean baseflow residence time was 9 months by both methods. These results indicate that baseflow residence time can be calculated accurately using recession analysis, and the method is less expensive than using environmental and/or artificial tracers. Published in 2002 by John Wiley & Sons, Ltd. 相似文献
11.
A. V. Desherevskii V. I. Zhuravlev A. N. Nikolsky A. Ya. Sidorin 《Seismic Instruments》2017,53(3):203-223
The first part of this work discussed the software requirements for working with geophysical monitoring data. This paper considers the technology for studying similar signals realized in the WinABD program. In contrast to many statistical analysis programs, WinABD supports a complete cycle of operations necessary for working with experimental time series. The software includes a database management system, a powerful research apparatus, and an interactive data visualization environment. The program makes it possible to analyze the structure of series and reveal dependences and interrelations between signals. There are a large number of nonstandard tools and methods necessary for everyday work with nonideal data. A moving time window technology is widely used, which makes it possible to study the development of all processes with time and reveal variations related to any events. A special “window-slamming” technology at the boundaries of a series makes it possible to carry out processing with a decreasing length of the series, which allows arbitrary combination of the applied methods. All of the procedures admit the presence of gaps in observations. For all data operations, a calendar time scale is used, which substantially improves convenience of operation. Correct joint processing of series with unidentical onset dates and noncoinciding observation periodicity is provided. 相似文献
12.
Analytical solutions for constant‐rate pumping tests are widely used to infer aquifer properties. In this note, we implement a methodology that approximates the time‐varying pumping record as a series of segments with linearly varying pumping rates. We validate our approach using an analytical solution for a sinusoidally varying pumping test. We also apply our methodology to analyze synthetic test data and compare the results with those from a commonly used method where rate variations are represented by a series of constant‐rate steps. 相似文献
13.
Hongyue Guo Xiaodong Liu 《Stochastic Environmental Research and Risk Assessment (SERRA)》2016,30(7):1875-1887
In this study, we propose a new segmentation algorithm to partition univariate and multivariate time series, where fuzzy clustering is realized for the segments formed in this way. The clustering algorithm involves a new objective function, which incorporates an extra variable related to segmentation, while dynamic time warping (DTW) is applied to determine distances between non-equal-length series. As optimizing the introduced objective function is a challenging task, we put forward an effective approach using dynamic programming (DP) algorithm. When calculating the DTW distance, a DP-based method is developed to reduce the computational complexity. In a series of experiments, both synthetic and real-world time series are used to evaluate the performance of the proposed algorithm. The results demonstrate higher effectiveness and advantages of the constructed algorithm when compared with the existing segmentation approaches. 相似文献
14.
How to improve the representation of hydrological processes in SWAT for a lowland catchment – temporal analysis of parameter sensitivity and model performance 下载免费PDF全文
下载免费PDF全文 Model diagnostic analyses help to improve the understanding of hydrological processes and their representation in hydrological models. A detailed temporal analysis detects periods of poor model performance and model components with potential for model improvements, which cannot be found by analysing the whole discharge time series. In this study, we aim to improve the understanding of hydrological processes by investigating the temporal dynamics of parameter sensitivity and of model performance for the Soil and Water Assessment Tool model applied to the Treene lowland catchment in Northern Germany. The temporal analysis shows that the parameter sensitivity varies temporally with high sensitivity for three groundwater parameters (groundwater time delay, baseflow recession constant and aquifer fraction coefficient) and one evaporation parameter (soil evaporation compensation factor). Whereas the soil evaporation compensation factor dominates in baseflow and resaturation periods, groundwater time delay, baseflow recession constant and aquifer fraction coefficient are dominant in the peak and recession phases. The temporal analysis of model performance identifies three clusters with different model performances, which can be related to different phases of the hydrograph. The lowest performance, when comparing six performance measures, is detected for the baseflow cluster. A spatially distributed analysis for six hydrological stations within the Treene catchment shows similar results for all stations. The linkage of periods with poor model performance to the dominant model components in these phases and with the related hydrological processes shows that the groundwater module has the highest potential for improvement. This temporal diagnostic analysis enhances the understanding of the Soil and Water Assessment Tool model and of the dominant hydrological processes in the lowland catchment. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
15.
《水文科学杂志》2012,57(1):21-32
ABSTRACTTwo contrasting methods have been proposed recently to predict the recession flow coefficient using past discharge information only. This study proposes a new method that attempts to obtain past discharge information that is minimally influenced by non-subsurface storage-controlled flows. The existing and new methods were tested using data from 324 US Geological Survey basins, and the new method was found to be superior to both existing methods in 265 basins. Furthermore, this study for the first time used past discharge-derived coefficients to predict recession discharge. The model performance was found to be satisfactory (NSE > 0.5) in 244 basins. Our results also show that the new framework may be useful in certain regions for predicting recession discharge in totally ungauged basins using past discharge information from nearby gauged basins. Overall, this study advances the idea that recession discharge can be predicted by just using past discharge data. 相似文献
16.
Recharge estimation is an important and challenging element of groundwater management and resource sustainability. Many recharge estimation methods have been developed with varying data requirements, applicable to different spatial and temporal scales. The variability and inherent uncertainty in recharge estimation motivates the recommended use of multiple methods to estimate and bound regional recharge estimates. Despite the inherent limitations of using daily gauged streamflow, recession curve displacement methods provide a convenient first‐order estimate as part of a multimethod hierarchical approach to estimate watershed‐scale annual recharge. The implementation of recession curve displacement recharge estimation in the United States Geologic Survey (USGS) RORA program relies on the subjective, operator‐specific selection of baseflow recession events to estimate a gauge‐specific recession index. This paper presents a parametric algorithm that objectively automates this tedious, subjective process, parameterizing and automating the implementation of recession curve displacement. Results using the algorithm reproduce regional estimates of groundwater recharge from the USGS Appalachian Valley and Piedmont Regional Aquifer‐System Analysis, with an average absolute error of less than 2%. The algorithm facilitates consistent, completely automated estimation of annual recharge that complements more rigorous data‐intensive techniques for recharge estimation. 相似文献
17.
A stochastic model for synthetic data generation is not available in the literature for daily flows of intermittent streams. Such a model is required in the planning and operation of structures on an intermittent stream for purposes where short time flow fluctuations are important. In this study a model is developed for such a case. The model consists of four steps: determination of the days on which flow occurs, determination of the days on which a flow increment occurs, determination of the magnitude of the flow increment, and calculation of the flow decrement on days when the flow is reduced. The first two steps are modelled by a three‐state Markov chain. In the third step, flow increments on the rising limb of the hydrograph are assumed to be gamma distributed. In the last step an exponential recession is used with two different coefficients. Parameters of the model are estimated from the observed daily stream flow data for each month of the year. The model is applied to a daily flow series of 35 years' length. It is seen that the model can preserve the short‐term characteristics (the ascension and recession curves and peaks) of the hydrograph in addition to the long‐term characteristics (mean, variance, skewness, lag‐one and higher lag autocorrelation coefficients, and zero flow percentage). The number of parameters of the model can be decreased by fitting Fourier series to their annual variation. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
18.
For a better management of water resources, the information on water stored in a basin in the form of snow is of immense use. Changes in the snow water storage with time influence the recession characteristics of the hydrographs. Recession is found to be slower in a basin when it contains higher snow water storage and becomes faster as the volume of stored water reduces. In other words, the recession coefficient is not constant throughout the melt season, it changes with time. In the present study, the possibility of assessing snow water storage at any time during the melt season using recession coefficients is examined. The hydrograph analyses have been made for the Glatzbach watershed in the Hohe Tauern region of the Austrian Alps. For this purpose, a relationship between snow water storage and the recession coefficients is developed. This study suggests a simple and useful approach to assess the snow water storage in a basin at any time during the snowmelt season. The information on the snow water storage of a basin can be obtained using a readily derived single parameter, the recession coefficient. The results are based on limited data, but they are sufficient to illustrate how the changes in snow water storage control the recession characteristics of the hydrographs. These investigations set the pace for further research in this area. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
19.
ABSTRACTEvaluation of a recession-based “top-down” model for distributed hourly runoff simulation in macroscale mountainous catchments is rare in the literature. We evaluated such a model for a 3090 km2 boreal catchment and its internal sub-catchments. The main research question is how the model performs when parameters are either estimated from streamflow recession or obtained by calibration. The model reproduced observed streamflow hydrographs (Nash-Sutcliffe efficiency up to 0.83) and flow duration curves. Transferability of parameters to the sub-catchments validates the performance of the model, and indicates an opportunity for prediction in ungauged sites. However, the cases of parameter estimation and calibration excluding the effects of runoff routing underestimate peak flows. The lower end of the recession and the minimum length of recession segments included are the main sources of uncertainty for parameter estimation. Despite the small number of calibrated parameters, the model is susceptible to parameter uncertainty and identifiability problems.
EDITOR D. Koutsoyiannis; ASSOCIATE EDITOR A. Carsteanu 相似文献
20.
Exploiting the use of physical information for the calibration of a lumped hydrological model 下载免费PDF全文
下载免费PDF全文 Salvatore Manfreda Leonardo Mita Silvano Fortunato Dal Sasso Caterina Samela Leonardo Mancusi 《水文研究》2018,32(10):1420-1433
In hydrological modelling, the challenge is to identify an optimal strategy to exploit tools and available observations in order to enhance model reliability. The increasing availability of data promotes the use of new calibration techniques able to make use of additional information on river basins. In the present study, a lumped hydrological model—designed with the aim of utilizing remotely sensed data—is introduced and calibrated, adopting four different schemes that adopt, to varying extents, available physical information. The physically consistent conceptualization of the hydrological model used allowed development of a step by step calibration based on a combination of information, such as remotely sensed data describing snow cover, recession curves obtained from streamflow measurements, and time series of surface run‐off obtained with a baseflow mathematical filter applied to the streamflow time‐series. Results suggest that the use of physical information in the calibration procedure tends to increase model reliability with respect to approaches where the parameters are calibrated using an overall statistic based, considerably or exclusively, on streamflow data. 相似文献