Skip to main content

Lund University Publications

LUND UNIVERSITY LIBRARIES

Application of an artificial intelligence technique enhanced with intelligent water drops for monthly reference evapotranspiration estimation

Ahmadi, Farshad ; Mehdizadeh, Saeid ; Mohammadi, Babak LU orcid ; Pham, Quoc Bao ; DOAN, Thi Ngoc Canh and Vo, Ngoc Duong (2021) In Agricultural Water Management 244.
Abstract

Reference evapotranspiration (ET0) is one of the most important parameters, which is required in many fields such as hydrological, agricultural, and climatological studies. Therefore, its estimation via reliable and accurate techniques is a necessity. The present study aims to estimate the monthly ET0 time series of six stations located in Iran. To achieve this objective, gene expression programming (GEP) and support vector regression (SVR) were used as standalone models. A novel hybrid model was then introduced through coupling the classical SVR with an optimization algorithm, namely intelligent water drops (IWD) (i.e., SVR−IWD). Two various types of scenarios were considered, including the climatic data- and... (More)

Reference evapotranspiration (ET0) is one of the most important parameters, which is required in many fields such as hydrological, agricultural, and climatological studies. Therefore, its estimation via reliable and accurate techniques is a necessity. The present study aims to estimate the monthly ET0 time series of six stations located in Iran. To achieve this objective, gene expression programming (GEP) and support vector regression (SVR) were used as standalone models. A novel hybrid model was then introduced through coupling the classical SVR with an optimization algorithm, namely intelligent water drops (IWD) (i.e., SVR−IWD). Two various types of scenarios were considered, including the climatic data- and antecedent ET0 data-based patterns. In the climatic data-based models, the effective climatic parameters were recognized by using two pre-processing techniques consisting of τ Kendall and entropy. It is worthy to mention that developing the hybrid SVR-IWD model as well as utilizing the τ Kendall and entropy approaches to discern the most influential weather parameters on ET0 are the innovations of current research. The results illustrated that the applied pre-processing methods introduced different climatic inputs to feed the models. The overall results of present study revealed that the proposed hybrid SVR-IWD model outperformed the standalone SVR one under both the considered scenarios when estimating the monthly ET0. In addition to the mentioned models, two types of empirical equations were also used including the Hargreaves−Samani (H−S) and Priestley−Taylor (P−T) in their original and calibrated versions. It was concluded that the calibrated versions showed superior performances compared to their original ones.

(Less)
Please use this url to cite or link to this publication:
author
; ; ; ; and
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Empirical models, Gene expression programming, Intelligent water drops, Reference evapotranspiration, Support vector regression
in
Agricultural Water Management
volume
244
article number
106622
publisher
Elsevier
external identifiers
  • scopus:85096201404
ISSN
0378-3774
DOI
10.1016/j.agwat.2020.106622
language
English
LU publication?
no
id
78a996a3-ba1e-447d-8aa2-fe3f9b835d87
date added to LUP
2020-12-30 04:59:55
date last changed
2022-04-26 22:52:49
@article{78a996a3-ba1e-447d-8aa2-fe3f9b835d87,
  abstract     = {{<p>Reference evapotranspiration (ET<sub>0</sub>) is one of the most important parameters, which is required in many fields such as hydrological, agricultural, and climatological studies. Therefore, its estimation via reliable and accurate techniques is a necessity. The present study aims to estimate the monthly ET<sub>0</sub> time series of six stations located in Iran. To achieve this objective, gene expression programming (GEP) and support vector regression (SVR) were used as standalone models. A novel hybrid model was then introduced through coupling the classical SVR with an optimization algorithm, namely intelligent water drops (IWD) (i.e., SVR−IWD). Two various types of scenarios were considered, including the climatic data- and antecedent ET<sub>0</sub> data-based patterns. In the climatic data-based models, the effective climatic parameters were recognized by using two pre-processing techniques consisting of τ Kendall and entropy. It is worthy to mention that developing the hybrid SVR-IWD model as well as utilizing the τ Kendall and entropy approaches to discern the most influential weather parameters on ET<sub>0</sub> are the innovations of current research. The results illustrated that the applied pre-processing methods introduced different climatic inputs to feed the models. The overall results of present study revealed that the proposed hybrid SVR-IWD model outperformed the standalone SVR one under both the considered scenarios when estimating the monthly ET<sub>0</sub>. In addition to the mentioned models, two types of empirical equations were also used including the Hargreaves−Samani (H−S) and Priestley−Taylor (P−T) in their original and calibrated versions. It was concluded that the calibrated versions showed superior performances compared to their original ones.</p>}},
  author       = {{Ahmadi, Farshad and Mehdizadeh, Saeid and Mohammadi, Babak and Pham, Quoc Bao and DOAN, Thi Ngoc Canh and Vo, Ngoc Duong}},
  issn         = {{0378-3774}},
  keywords     = {{Empirical models; Gene expression programming; Intelligent water drops; Reference evapotranspiration; Support vector regression}},
  language     = {{eng}},
  month        = {{02}},
  publisher    = {{Elsevier}},
  series       = {{Agricultural Water Management}},
  title        = {{Application of an artificial intelligence technique enhanced with intelligent water drops for monthly reference evapotranspiration estimation}},
  url          = {{http://dx.doi.org/10.1016/j.agwat.2020.106622}},
  doi          = {{10.1016/j.agwat.2020.106622}},
  volume       = {{244}},
  year         = {{2021}},
}