Modeling of daily pan evaporation in sub tropical climates using ANN, LS-SVR, Fuzzy Logic, and ANFIS

• Published in: Expert systems with applications Vol. 41; no. 11; pp. 5267 - 5276
• Main Authors: Goyal, Manish Kumar, Bharti, Birendra, Quilty, John, Adamowski, Jan, Pandey, Ashish
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Ltd 01.09.2014; Elsevier
• Subjects: Accuracy; Adaptive systems; ANFIS; ANN; Applied sciences; Artificial intelligence; Artificial neural networks; Climate; Computer science; control theory; systems; Connectionism. Neural networks; Data processing. List processing. Character string processing; Earth sciences; Earth, ocean, space; Evaporation; Exact sciences and technology; External geophysics; Fuzzy Logic; Gamma Test; Hydrology. Hydrogeology; Learning theory; LS-SVR; Memory organisation. Data processing; Meteorology; Modeling; Neural networks; Software; Water resources; ANN; Evaporation; ANFIS; Modeling; Fuzzy Logic; LS-SVR; Gamma Test; Input output; regression analysis; neural networks; tropical zone; subtropical zone; Fuzzy neural nets; artificial intelligence; Variance; Backpropagation algorithm; Levenberg Marquardt algorithm; Least squares method; Vector support machine; Feedforward; Bayes estimation; Backpropagation; Meteorological observation; rainfall; fuzzy logic; Empirical method; Meteorological variable; water resource management; Maximum temperature; statistical analysis; evaporation
• ISSN: 0957-4174; 1873-6793
• DOI: 10.1016/j.eswa.2014.02.047

•Four new machine learning techniques explored for pan evaporation estimation.•The study area was the sub-tropical Karso watershed in India.•Traditional Hargreaves and Samani, and Stephens–Stewart method, were also explored.•Fuzzy Logic and LS-SVR approaches were found to be the most accurate methods. This paper investigates the abilities of Artificial Neural Networks (ANN), Least Squares – Support Vector Regression (LS-SVR), Fuzzy Logic, and Adaptive Neuro-Fuzzy Inference System (ANFIS) techniques to improve the accuracy of daily pan evaporation estimation in sub-tropical climates. Meteorological data from the Karso watershed in India (consisting of 3801 daily records from the year 2000 to 2010) were used to develop and test the models for daily pan evaporation estimation. The measured meteorological variables include daily observations of rainfall, minimum and maximum air temperatures, minimum and maximum humidity, and sunshine hours. Prior to model development, the Gamma Test (GT) was used to derive estimates of the noise variance for each input–output set in order to identify the most useful predictors for use in the machine learning approaches used in this study. The ANN models consisted of feed forward backpropagation (FFBP) models with Bayesian Regularization (BR), along with the Levenberg–Marquardt (LM) algorithm. A comparison was made between the estimates provided by the ANN, LS-SVR, Fuzzy Logic, and ANFIS models. The empirical Hargreaves and Samani method (HGS), as well as the Stephens–Stewart (SS) method, were also considered for comparison with the newer machine learning methods. The Root Mean Square Error (RMSE) and Correlation Coefficient (CORR) were the statistical performance indices that were used to evaluate the accuracy of the various models. Based on the comparison, it was found that the Fuzzy Logic and LS-SVR approaches can be employed successfully in modeling the daily evaporation process from the available climatic data. In addition, results showed that the machine learning models outperform the traditional HGS and SS empirical methods.