scholarly journals IPEAT+: A Built-In Optimization and Automatic Calibration Tool of SWAT+

Water ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 1681 ◽  
Author(s):  
Haw Yen ◽  
Seonggyu Park ◽  
Jeffrey G. Arnold ◽  
Raghavan Srinivasan ◽  
Celray James Chawanda ◽  
...  
Keyword(s):  
Open Source ◽  
Assessment Tool ◽  
Swat Model ◽  
Optimization Technique ◽  
Source Code ◽  
Watershed Modeling ◽  
Automatic Calibration ◽  
Analysis Tool ◽  
New Generation ◽  
Calibration Tool

For almost 30 years, the Soil and Water Assessment Tool (SWAT) has been successfully implemented to address issues around various scientific subjects in the world. On the other hand, it has been reaching to the limit of potential flexibility in further development by the current structure. The new generation SWAT, dubbed SWAT+, was released recently with entirely new coding features. SWAT+ is designed to have far more advanced functions and capacities to handle challenging watershed modeling tasks for hydrologic and water quality processes. However, it is still inevitable to conduct model calibration before the SWAT+ model is applied to engineering projects and research programs. The primary goal of this study is to develop an open-source, easy-to-operate automatic calibration tool for SWAT+, dubbed IPEAT+ (Integrated Parameter Estimation and Uncertainty Analysis Tool Plus). There are four major advantages: (i) Open-source code to general users; (ii) compiled and integrated directly with SWAT+ source code as a single executable; (iii) supported by the SWAT developer group; and, (iv) built with efficient optimization technique. The coupling work between IPEAT+ and SWAT+ is fairly simple, which can be conducted by users with minor efforts. IPEAT+ will be regularly updated with the latest SWAT+ revision. If users would like to integrate IPEAT+ with various versions of SWAT+, only few lines in the SWAT+ source code are required to be updated. IPEAT+ is the first automatic calibration tool integrated with SWAT+ source code. Users can take advantage of the tool to pursue more cutting-edge and forward-thinking scientific questions.

scholarly journals Calibration and validation of SWAT model and estimation of water balance components of Shaya mountainous watershed, Southeastern Ethiopia

2013 ◽  
Vol 10 (11) ◽  
pp. 13955-13978 ◽  
Author(s):  
A. A. Shawul ◽  
T. Alamirew ◽  
M. O. Dinka
Keyword(s):  
Best Management Practices ◽  
Management Practices ◽  
Assessment Tool ◽  
Swat Model ◽  
Watershed Modeling ◽  
Coefficient Of Determination ◽  
Water Yield ◽  
Time Step ◽  
Monthly Streamflow ◽  
Mountainous Watershed

Abstract. To utilize water resources in a sustainable manner, it is necessary to understand the quantity and quality in space and time. This study was initiated to evaluate the performance and applicability of the physically based Soil and Water Assessment Tool (SWAT) model in analyzing the influence of hydrologic parameters on the streamflow variability and estimation of monthly and seasonal water yield at the outlet of Shaya mountainous watershed. The calibrated SWAT model performed well for simulation of monthly streamflow. Statistical model performance measures, coefficient of determination (r2) of 0.71, the Nash–Sutcliffe simulation efficiency (ENS) of 0.71 and percent difference (D) of 3.69, for calibration and 0.76, 0.75 and 3.30, respectively for validation, indicated good performance of the model simulation on monthly time step. Mean monthly and annual water yield simulated with the calibrated model were found to be 25.8 mm and 309.0 mm, respectively. Overall, the model demonstrated good performance in capturing the patterns and trend of the observed flow series, which confirmed the appropriateness of the model for future scenario simulation. Therefore, SWAT model can be taken as a potential tool for simulation of the hydrology of unguaged watershed in mountainous areas, which behave hydro-meteorologically similar with Shaya watershed. Future studies on Shaya watershed modeling should address the issues related to water quality and evaluate best management practices.

scholarly journals Integration of soil hydraulic characteristics derived from pedotransfer functions into hydrological models: evaluation of its effects on simulation uncertainty

2016 ◽  
Vol 47 (5) ◽  
pp. 964-978 ◽  
Author(s):  
Wenchao Sun ◽  
Xiaolei Yao ◽  
Na Cao ◽  
Zongxue Xu ◽  
Jingshan Yu
Keyword(s):  
Soil Water ◽  
Assessment Tool ◽  
Swat Model ◽  
Pedotransfer Functions ◽  
Soil Parameters ◽  
Analysis Tool ◽  
Hydrological Models ◽  
Water Characteristics ◽  
Soil Hydraulic ◽  
Generalized Likelihood Uncertainty Estimation

Aimed at reducing simulation uncertainty of hydrological models in data-sparse basins where soil hydraulic data are unavailable, a method of estimating soil water parameters of soil and water assessment tool (SWAT) from readily available soil information using pedotransfer functions was introduced. The method was evaluated through a case study of Jinjiang Basin, China and was performed based on comparison between two model calibrations: (1) soil parameters estimated from pedotransfer functions and other parameters obtained from calibration; and (2) all parameters derived from calibration. The generalized likelihood uncertainty estimation (GLUE) was used as a model calibration and uncertainty analysis tool. The results show that information contained in streamflow data is insufficient to derive physically reasonable soil parameter values via calibration. The proposed method can reduce simulation uncertainty, resulting from greater average performance of behavioral parameter sets identified by GLUE. Exploring the parameter space reveals that the means of estimating soil parameters has little influence on other parameters. These facts indicate the decrease in uncertainty most likely results from a more realistic description of soil water characteristics than calibration. Thus, the proposed method is superior to calibration for estimating soil parameters of SWAT model when basin data are sparse.

scholarly journals Optimization and Application of Snow Melting Modules in SWAT Model for the Alpine Regions of Northern China

Water ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 636 ◽  
Author(s):  
Yan Liu ◽  
Geng Cui ◽  
Hongyan Li
Keyword(s):  
Assessment Tool ◽  
Swat Model ◽  
Source Code ◽  
Northern China ◽  
Runoff Simulation ◽  
Simulation Accuracy ◽  
Local Conditions ◽  
The North ◽  
Alpine Regions ◽  
The Difference

Snowmelt is the main source of runoff in the alpine regions of northern China. When using the soil and water assessment tool (SWAT) to simulate snowmelt runoff, the snowmelt date and snowmelt factor parameters are set according to the North American values. To improve the accuracy of the runoff simulation in northern China, we innovatively used a baseflow segmentation method to determine the snowmelt time, taking temperature as a reference. The snowmelt period was extracted from statistical data, and the corresponding parameters in the source code of SWAT were optimized for the study area. After the calibration was completed, the modified simulation value was compared with the original code simulation value. The simulation accuracy of the daily runoff was improved, and we found that the greater the difference between the source code simulation value and the observed value was, the better the simulation accuracy. Therefore, modifying the source code in SWAT is an effective way to improve the accuracy of simulations of Alpine regions in Northern China. The results show that adjustments to the snowmelt modules of SWAT to reflect local conditions can be an effective way to improve the predictions.

scholarly journals Endicheck: Dynamic Analysis for Detecting Endianness Bugs

2020 ◽  
pp. 254-270
Author(s):  
Roman Kápl ◽  
Pavel Parízek
Keyword(s):  
Dynamic Analysis ◽  
Open Source ◽  
Computer Systems ◽  
Source Code ◽  
Analysis Tool ◽  
Linux Kernel ◽  
Numeric Data ◽  
The Given ◽  
Code Annotations

Abstract Computers store numbers in two mutually incompatible ways: little-endian or big-endian. They differ in the order of bytes within representation of numbers. This ordering is called endianness. When two computer systems, programs or devices communicate, they must agree on which endianness to use, in order to avoid misinterpretation of numeric data values. We present Endicheck, a dynamic analysis tool for detecting endianness bugs, which is based on the popular Valgrind framework. It helps developers to find those code locations in their program where they forgot to swap bytes properly. Endicheck requires less source code annotations than existing tools, such as Sparse used by Linux kernel developers, and it can also detect potential bugs that would only manifest if the given program was run on computer with an opposite endianness. Our approach has been evaluated and validated on the Radeon SI Linux OpenGL driver, which is known to contain endianness-related bugs, and on several open-source programs. Results of experiments show that Endicheck can successfully identify many endianness-related bugs and provide useful diagnostic messages together with the source code locations of respective bugs.

scholarly journals Optimal Calibration and Uncertainty Analysis of SWAT for an Arid Climate

2017 ◽  
Vol 10 ◽  
pp. 117862211773179 ◽  
Author(s):  
Milad Jajarmizadeh ◽  
Lariyah Mohd Sidek ◽  
Sobri Harun ◽  
Mohsen Salarpour
Keyword(s):  
Uncertainty Analysis ◽  
Assessment Tool ◽  
Swat Model ◽  
Watershed Modeling ◽  
Flow Simulation ◽  
Performance Criteria ◽  
Global Method ◽  
Optimum Parameters ◽  
Sensitive Parameters ◽  
Water Assessment

One of the major issues for semidistributed models is calibration of sensitive parameters. This study compared 3 scenarios for Soil and Water Assessment Tool (SWAT) model for calibration and uncertainty. Roodan watershed has been selected for simulation of daily flow in southern part of Iran with an area of 10 570 km2. After preparation of required data and implementation of the SWAT model, sensitivity analysis has been performed by Latin Hypercube One-factor-At-a-Time method on those parameters which are effective for flow simulation. Then, SWAT Calibration and Uncertainty Program (SWAT-CUP) has been used for calibration and uncertainty analysis. Three schemes for calibration were followed for the Roodan watershed modeling in calibration analysis as evolution. These include the following: the global method (scheme 1), this is a method that takes in all globally adjusted sensitive parameters for the whole watershed; the discretization method (scheme 2), this method considered the dominant features in calibration such as land use and soil type; the optimum parameters method (scheme 3), this method only adjusted those sensitive parameters by considering the effectiveness of their features. The results show that scheme 3 has better performance criteria for calibration and uncertainty analysis. Nash-Sutcliffe (NS) coefficient has been obtained 0.75 for scheme 3. However, schemes 1 and 2 resulted in NS 0.71 and 0.74, respectively, between predicted and observed daily flows. Moreover, percentage bias (P-bias) obtained was 6.7, 5.2, and 1.5 for schemes 1, 2, and 3, respectively. The result also shows that condition of parameters (parameter set) during calibration in SWAT-CUP program model has an important role to increase the performance of the model.

scholarly journals Improving Alpine Summertime Streamflow Simulations by the Incorporation of Evapotranspiration Data

Water ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 112 ◽  
Author(s):  
Kenneth Tobin ◽  
Marvin Bennett
Keyword(s):  
Assessment Tool ◽  
Swat Model ◽  
Watershed Modeling ◽  
High Sensitivity ◽  
Early Summer ◽  
Objective Metrics ◽  
North Fork ◽  
Moderate Resolution ◽  
Parameter Values ◽  
Water Assessment

Over the last decade, autocalibration routines have become commonplace in watershed modeling. This approach is most often used to simulate a streamflow at a basin’s outlet. In alpine settings, spring/early summer snowmelt is by far the dominant signal in this system. Therefore, there is great potential for a modeled watershed to underperform during other times of the year. This tendency has been noted in many prior studies. In this work, the Soil and Water Assessment Tool (SWAT) model was auto-calibrated with the SUFI-2 routine. A mountainous watershed from Idaho was examined (Upper North Fork). In this study, this basin was calibrated using three estimates of evapotranspiration (ET): Moderate Resolution Imagining Spectrometer (MODIS), Simplified Surface Energy Balance, and Global Land Evaporation: the Amsterdam Model. The MODIS product in particular, had the greatest utility in helping to constrain SWAT parameters that have a high sensitivity to ET. Streamflow simulations that utilize these ET parameter values have improved recessional and summertime streamflow performances during calibration (2007 to 2011) and validation (2012 to 2014) periods. Streamflow performance was monitored with standard objective metrics (Bias and Nash Sutcliffe coefficients) that quantified overall, recessional, and summertime peak flows. This approach yielded dramatic enhancements for all three observations. These results demonstrate the utility of this approach for improving watershed modeling fidelity outside the main snowmelt season.

Watershed modeling using large-scale distributed computing in Condor and the Soil and Water Assessment Tool model

SIMULATION ◽  
2011 ◽  
Vol 88 (3) ◽  
pp. 365-380 ◽  
Author(s):  
Margaret W Gitau ◽  
Li-Chi Chiang ◽  
Mohamed Sayeed ◽  
Indrajeet Chaubey
Keyword(s):  
Water Quality ◽  
Best Management Practices ◽  
Large Scale ◽  
Management Practices ◽  
Assessment Tool ◽  
Swat Model ◽  
Watershed Modeling ◽  
Management Decisions ◽  
Water Assessment ◽  
Soil And Water

Models are increasingly being used to quantify the effects of best management practices (BMPs) on water quality. While these models offer the ability to study multiple BMP scenarios, and to analyze impacts of various management decisions on watershed response, associated analyses can be very computationally intensive due to a large number of runs needed to fully capture the various uncertainties in the model outputs. There is, thus, the need to develop suitable and efficient techniques to handle such comprehensive model evaluations. We demonstrate a novel approach to accomplish a large number of model runs with Condor, a distributed high-throughput computing framework for model runs with the Soil and Water Assessment Tool (SWAT) model. This application required more than 43,000 runs of the SWAT model to evaluate the impacts of 172 different watershed management decisions combined with weather uncertainty on water quality. The SWAT model was run in the Condor environment implemented on the TeraGrid. This framework significantly reduced the model run time from 2.5 years to 18 days and enabled us to perform comprehensive BMP analyses that may not have been possible with traditional model runs on a few desktop computers. The Condor system can be used effectively to make Monte Carlo analyses of complex watershed models requiring a large number of computational cycles.

scholarly journals Watershed subdivision and weather input effect on streamflow simulation using SWAT model

2021 ◽  
Author(s):  
Firas Alsilibe ◽  
Katalin Bene
Keyword(s):  
Assessment Tool ◽  
Swat Model ◽  
Watershed Modeling ◽  
Model Input ◽  
The Impact ◽  
Water Assessment ◽  
Watershed Processes ◽  
Streamflow Simulation ◽  
Soil And Water

Abstract In watershed modeling research, it is practical to subdivide a watershed into smaller units or sub-watersheds for modeling purposes. The ability of a model to simulate the watershed system depends on how well watershed processes are represented by the model and how well the watershed system is described by model input. This study is conducted to evaluate the impact of watershed subdivision and different weather input datasets on streamflow simulations using the soil and water assessment tool model. For this purpose, Cuhai-Bakonyér watershed was chosen as a study area. Two climate databases and four subdivision variations levels were evaluated. The model streamflow predictions slightly effected by subdivision impact. The climate datasets showed significant differences in streamflow predictions.

Impact of Clone Refactoring on External Quality Attributes of Open Source Softwares

2018 ◽  
pp. 86-94
Author(s):  
Himanshi Vashisht ◽  
Sanjay Bharadwaj ◽  
Sushma Sharma
Keyword(s):  
Open Source ◽  
Internal Structure ◽  
Software Quality ◽  
Source Code ◽  
Quality Attributes ◽  
Software Component ◽  
External Quality ◽  
Code Refactoring ◽  
Observable Behaviour

Code refactoring is a “Process of restructuring an existing source code.”. It also helps in improving the internal structure of the code without really affecting its external behaviour”. It changes a source code in such a way that it does not alter the external behaviour yet still it improves its internal structure. It is a way to clean up code that minimizes the chances of introducing bugs. Refactoring is a change made to the internal structure of a software component to make it easier to understand and cheaper to modify, without changing the observable behaviour of that software component. Bad smells indicate that there is something wrong in the code that have to refactor. There are different tools that are available to identify and emove these bad smells. A software has two types of quality attributes- Internal and external. In this paper we will study the effect of clone refactoring on software quality attributes.

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