Penman and Thornthwaite Equations for Estimating Reference Evapotranspiration Under Semi-Arid Environment

Muhammad Hafeez; Allah Bakhsh Gulshan; Abdul Basit; Zia Ahmad Chattha; Alamgir Akhtar Khan; Muhammad Adnan Majeed; Fatima Tahira

doi:doi:10.11648/j.jps.20200805.16

Penman and Thornthwaite Equations for Estimating Reference Evapotranspiration Under Semi-Arid Environment

Muhammad Hafeez, Allah Bakhsh Gulshan, Abdul Basit, Zia Ahmad Chattha, Alamgir Akhtar Khan, Muhammad Adnan Majeed, Fatima Tahira

Published in Journal of Plant Sciences (Volume 8, Issue 5)

Received: 10 April 2020 Accepted: 22 August 2020 Published: 24 September 2020

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Abstract

The estimation of reference evapotranspiration (ETo) is required for effective development and management of agriculture water systems. In order to define the most accurate method to estimate ETo in semi-arid climatic environment of Faisalabad, Lahore and Peshawar. Penman ETo method and Thornthwaite ETo method are compared with standard Penman-Monteith (PM) ETo method. The statistical results show that the Penman ETo method overestimate ETo as compared to the PM ETo method in all the semi-arid climatic regions of Faisalabad, Lahore and Peshawar by 34.91%, 39.51% and 30.75%, respectively. The coefficient of determination (R²) were 0.98, 0.98 and 0.99 at Faisalabad, Lahore and Peshawar weather stations, respectively. The root mean square error (RMSE) are 2.47 mm/day, 2.64 mm/day and 2.19 mm/day at Faisalabad, Lahore and Peshawar weather station, respectively. The mean bias error (MBE) of-2.41 mm/day,-2.58 mm/day and-2.13 mm/day are noted at Faisalabad, Lahore and Peshawar weather stations, respectively. The statistical results of Thornthwaite (Th) ETo method with PM ETo method indicate underestimation of ETo in winter season and overestimation of ETo in summer season by 13.81%, 22.43% and 14.54% at Faisalabad, Lahore and Peshawar stations, respectively. The coefficient of determination (R²) of Thornthwait ETo method when compared with PM ETo method 0.92, 0.89 and 0.95 are noted at Faisalabad, Lahore and Peshawar weather stations, respectively. The root mean square error (RMSE) are 2.14 mm/day, 2.36 mm/day and 1.16 mm/day at Faisalabad, Lahore and Peshawar weather stations, respectively. The mean bias error (MBE) are-0.68 mm/day,-1.12 mm/day and 0.61 mm/day at Faisalabad, Lahore and Peshawar weather stations, respectively. Overall, Thornthwaite method gave better estimation of ETo than Penman ETo method at all the Weather stations.

Published in	Journal of Plant Sciences (Volume 8, Issue 5)
DOI	10.11648/j.jps.20200805.16
Page(s)	146-151
Creative Commons	This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.
Copyright	Copyright © The Author(s), 2020. Published by Science Publishing Group

Keywords

Penman, Thornthwaite, Penman-Monteith, Reference Evapotranspiration, Semi-arid

References

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Muhammad Hafeez, Allah Bakhsh Gulshan, Abdul Basit, Zia Ahmad Chattha, Alamgir Akhtar Khan, et al. (2020). Penman and Thornthwaite Equations for Estimating Reference Evapotranspiration Under Semi-Arid Environment. Journal of Plant Sciences, 8(5), 146-151. https://doi.org/10.11648/j.jps.20200805.16

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ACS Style

Muhammad Hafeez; Allah Bakhsh Gulshan; Abdul Basit; Zia Ahmad Chattha; Alamgir Akhtar Khan, et al. Penman and Thornthwaite Equations for Estimating Reference Evapotranspiration Under Semi-Arid Environment. J. Plant Sci. 2020, 8(5), 146-151. doi: 10.11648/j.jps.20200805.16

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AMA Style

Muhammad Hafeez, Allah Bakhsh Gulshan, Abdul Basit, Zia Ahmad Chattha, Alamgir Akhtar Khan, et al. Penman and Thornthwaite Equations for Estimating Reference Evapotranspiration Under Semi-Arid Environment. J Plant Sci. 2020;8(5):146-151. doi: 10.11648/j.jps.20200805.16

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@article{10.11648/j.jps.20200805.16,
  author = {Muhammad Hafeez and Allah Bakhsh Gulshan and Abdul Basit and Zia Ahmad Chattha and Alamgir Akhtar Khan and Muhammad Adnan Majeed and Fatima Tahira},
  title = {Penman and Thornthwaite Equations for Estimating Reference Evapotranspiration Under Semi-Arid Environment},
  journal = {Journal of Plant Sciences},
  volume = {8},
  number = {5},
  pages = {146-151},
  doi = {10.11648/j.jps.20200805.16},
  url = {https://doi.org/10.11648/j.jps.20200805.16},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.jps.20200805.16},
  abstract = {The estimation of reference evapotranspiration (ETo) is required for effective development and management of agriculture water systems. In order to define the most accurate method to estimate ETo in semi-arid climatic environment of Faisalabad, Lahore and Peshawar. Penman ETo method and Thornthwaite ETo method are compared with standard Penman-Monteith (PM) ETo method. The statistical results show that the Penman ETo method overestimate ETo as compared to the PM ETo method in all the semi-arid climatic regions of Faisalabad, Lahore and Peshawar by 34.91%, 39.51% and 30.75%, respectively. The coefficient of determination (R2) were 0.98, 0.98 and 0.99 at Faisalabad, Lahore and Peshawar weather stations, respectively. The root mean square error (RMSE) are 2.47 mm/day, 2.64 mm/day and 2.19 mm/day at Faisalabad, Lahore and Peshawar weather station, respectively. The mean bias error (MBE) of-2.41 mm/day,-2.58 mm/day and-2.13 mm/day are noted at Faisalabad, Lahore and Peshawar weather stations, respectively. The statistical results of Thornthwaite (Th) ETo method with PM ETo method indicate underestimation of ETo in winter season and overestimation of ETo in summer season by 13.81%, 22.43% and 14.54% at Faisalabad, Lahore and Peshawar stations, respectively. The coefficient of determination (R2) of Thornthwait ETo method when compared with PM ETo method 0.92, 0.89 and 0.95 are noted at Faisalabad, Lahore and Peshawar weather stations, respectively. The root mean square error (RMSE) are 2.14 mm/day, 2.36 mm/day and 1.16 mm/day at Faisalabad, Lahore and Peshawar weather stations, respectively. The mean bias error (MBE) are-0.68 mm/day,-1.12 mm/day and 0.61 mm/day at Faisalabad, Lahore and Peshawar weather stations, respectively. Overall, Thornthwaite method gave better estimation of ETo than Penman ETo method at all the Weather stations.},
 year = {2020}
}

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TY  - JOUR
T1  - Penman and Thornthwaite Equations for Estimating Reference Evapotranspiration Under Semi-Arid Environment
AU  - Muhammad Hafeez
AU  - Allah Bakhsh Gulshan
AU  - Abdul Basit
AU  - Zia Ahmad Chattha
AU  - Alamgir Akhtar Khan
AU  - Muhammad Adnan Majeed
AU  - Fatima Tahira
Y1  - 2020/09/24
PY  - 2020
N1  - https://doi.org/10.11648/j.jps.20200805.16
DO  - 10.11648/j.jps.20200805.16
T2  - Journal of Plant Sciences
JF  - Journal of Plant Sciences
JO  - Journal of Plant Sciences
SP  - 146
EP  - 151
PB  - Science Publishing Group
SN  - 2331-0731
UR  - https://doi.org/10.11648/j.jps.20200805.16
AB  - The estimation of reference evapotranspiration (ETo) is required for effective development and management of agriculture water systems. In order to define the most accurate method to estimate ETo in semi-arid climatic environment of Faisalabad, Lahore and Peshawar. Penman ETo method and Thornthwaite ETo method are compared with standard Penman-Monteith (PM) ETo method. The statistical results show that the Penman ETo method overestimate ETo as compared to the PM ETo method in all the semi-arid climatic regions of Faisalabad, Lahore and Peshawar by 34.91%, 39.51% and 30.75%, respectively. The coefficient of determination (R2) were 0.98, 0.98 and 0.99 at Faisalabad, Lahore and Peshawar weather stations, respectively. The root mean square error (RMSE) are 2.47 mm/day, 2.64 mm/day and 2.19 mm/day at Faisalabad, Lahore and Peshawar weather station, respectively. The mean bias error (MBE) of-2.41 mm/day,-2.58 mm/day and-2.13 mm/day are noted at Faisalabad, Lahore and Peshawar weather stations, respectively. The statistical results of Thornthwaite (Th) ETo method with PM ETo method indicate underestimation of ETo in winter season and overestimation of ETo in summer season by 13.81%, 22.43% and 14.54% at Faisalabad, Lahore and Peshawar stations, respectively. The coefficient of determination (R2) of Thornthwait ETo method when compared with PM ETo method 0.92, 0.89 and 0.95 are noted at Faisalabad, Lahore and Peshawar weather stations, respectively. The root mean square error (RMSE) are 2.14 mm/day, 2.36 mm/day and 1.16 mm/day at Faisalabad, Lahore and Peshawar weather stations, respectively. The mean bias error (MBE) are-0.68 mm/day,-1.12 mm/day and 0.61 mm/day at Faisalabad, Lahore and Peshawar weather stations, respectively. Overall, Thornthwaite method gave better estimation of ETo than Penman ETo method at all the Weather stations.
VL  - 8
IS  - 5
ER  -

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Author Information

Muhammad Hafeez

Department of Agricultural Engineering, Faculty of Agricultural sciences and Technology, Bahauddin Zakariya University, Multan, Pakistan
Allah Bakhsh Gulshan

Department of Botany, Ghazi University, Dera Ghazi Khan, Pakistan
Abdul Basit

Department of Botany, Ghazi University, Dera Ghazi Khan, Pakistan
Zia Ahmad Chattha

Faculty of Agricultural Engineering, University of Agriculture, Faisalabad, Pakistan
Alamgir Akhtar Khan

Department of Agricultural Engineering, Muhammad Nawaz Sharif University of Agriculture, Multan, Pakistan
Muhammad Adnan Majeed

School of Engineering, University of Waikato, Hamilton, New Zealand
Fatima Tahira

Department of Mathematics, Institute of Southern Punjab, Multan, Pakistan

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APA Style

Muhammad Hafeez, Allah Bakhsh Gulshan, Abdul Basit, Zia Ahmad Chattha, Alamgir Akhtar Khan, et al. (2020). Penman and Thornthwaite Equations for Estimating Reference Evapotranspiration Under Semi-Arid Environment. Journal of Plant Sciences, 8(5), 146-151. https://doi.org/10.11648/j.jps.20200805.16

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ACS Style

Muhammad Hafeez; Allah Bakhsh Gulshan; Abdul Basit; Zia Ahmad Chattha; Alamgir Akhtar Khan, et al. Penman and Thornthwaite Equations for Estimating Reference Evapotranspiration Under Semi-Arid Environment. J. Plant Sci. 2020, 8(5), 146-151. doi: 10.11648/j.jps.20200805.16

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AMA Style

Muhammad Hafeez, Allah Bakhsh Gulshan, Abdul Basit, Zia Ahmad Chattha, Alamgir Akhtar Khan, et al. Penman and Thornthwaite Equations for Estimating Reference Evapotranspiration Under Semi-Arid Environment. J Plant Sci. 2020;8(5):146-151. doi: 10.11648/j.jps.20200805.16

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@article{10.11648/j.jps.20200805.16,
  author = {Muhammad Hafeez and Allah Bakhsh Gulshan and Abdul Basit and Zia Ahmad Chattha and Alamgir Akhtar Khan and Muhammad Adnan Majeed and Fatima Tahira},
  title = {Penman and Thornthwaite Equations for Estimating Reference Evapotranspiration Under Semi-Arid Environment},
  journal = {Journal of Plant Sciences},
  volume = {8},
  number = {5},
  pages = {146-151},
  doi = {10.11648/j.jps.20200805.16},
  url = {https://doi.org/10.11648/j.jps.20200805.16},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.jps.20200805.16},
  abstract = {The estimation of reference evapotranspiration (ETo) is required for effective development and management of agriculture water systems. In order to define the most accurate method to estimate ETo in semi-arid climatic environment of Faisalabad, Lahore and Peshawar. Penman ETo method and Thornthwaite ETo method are compared with standard Penman-Monteith (PM) ETo method. The statistical results show that the Penman ETo method overestimate ETo as compared to the PM ETo method in all the semi-arid climatic regions of Faisalabad, Lahore and Peshawar by 34.91%, 39.51% and 30.75%, respectively. The coefficient of determination (R2) were 0.98, 0.98 and 0.99 at Faisalabad, Lahore and Peshawar weather stations, respectively. The root mean square error (RMSE) are 2.47 mm/day, 2.64 mm/day and 2.19 mm/day at Faisalabad, Lahore and Peshawar weather station, respectively. The mean bias error (MBE) of-2.41 mm/day,-2.58 mm/day and-2.13 mm/day are noted at Faisalabad, Lahore and Peshawar weather stations, respectively. The statistical results of Thornthwaite (Th) ETo method with PM ETo method indicate underestimation of ETo in winter season and overestimation of ETo in summer season by 13.81%, 22.43% and 14.54% at Faisalabad, Lahore and Peshawar stations, respectively. The coefficient of determination (R2) of Thornthwait ETo method when compared with PM ETo method 0.92, 0.89 and 0.95 are noted at Faisalabad, Lahore and Peshawar weather stations, respectively. The root mean square error (RMSE) are 2.14 mm/day, 2.36 mm/day and 1.16 mm/day at Faisalabad, Lahore and Peshawar weather stations, respectively. The mean bias error (MBE) are-0.68 mm/day,-1.12 mm/day and 0.61 mm/day at Faisalabad, Lahore and Peshawar weather stations, respectively. Overall, Thornthwaite method gave better estimation of ETo than Penman ETo method at all the Weather stations.},
 year = {2020}
}

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TY  - JOUR
T1  - Penman and Thornthwaite Equations for Estimating Reference Evapotranspiration Under Semi-Arid Environment
AU  - Muhammad Hafeez
AU  - Allah Bakhsh Gulshan
AU  - Abdul Basit
AU  - Zia Ahmad Chattha
AU  - Alamgir Akhtar Khan
AU  - Muhammad Adnan Majeed
AU  - Fatima Tahira
Y1  - 2020/09/24
PY  - 2020
N1  - https://doi.org/10.11648/j.jps.20200805.16
DO  - 10.11648/j.jps.20200805.16
T2  - Journal of Plant Sciences
JF  - Journal of Plant Sciences
JO  - Journal of Plant Sciences
SP  - 146
EP  - 151
PB  - Science Publishing Group
SN  - 2331-0731
UR  - https://doi.org/10.11648/j.jps.20200805.16
AB  - The estimation of reference evapotranspiration (ETo) is required for effective development and management of agriculture water systems. In order to define the most accurate method to estimate ETo in semi-arid climatic environment of Faisalabad, Lahore and Peshawar. Penman ETo method and Thornthwaite ETo method are compared with standard Penman-Monteith (PM) ETo method. The statistical results show that the Penman ETo method overestimate ETo as compared to the PM ETo method in all the semi-arid climatic regions of Faisalabad, Lahore and Peshawar by 34.91%, 39.51% and 30.75%, respectively. The coefficient of determination (R2) were 0.98, 0.98 and 0.99 at Faisalabad, Lahore and Peshawar weather stations, respectively. The root mean square error (RMSE) are 2.47 mm/day, 2.64 mm/day and 2.19 mm/day at Faisalabad, Lahore and Peshawar weather station, respectively. The mean bias error (MBE) of-2.41 mm/day,-2.58 mm/day and-2.13 mm/day are noted at Faisalabad, Lahore and Peshawar weather stations, respectively. The statistical results of Thornthwaite (Th) ETo method with PM ETo method indicate underestimation of ETo in winter season and overestimation of ETo in summer season by 13.81%, 22.43% and 14.54% at Faisalabad, Lahore and Peshawar stations, respectively. The coefficient of determination (R2) of Thornthwait ETo method when compared with PM ETo method 0.92, 0.89 and 0.95 are noted at Faisalabad, Lahore and Peshawar weather stations, respectively. The root mean square error (RMSE) are 2.14 mm/day, 2.36 mm/day and 1.16 mm/day at Faisalabad, Lahore and Peshawar weather stations, respectively. The mean bias error (MBE) are-0.68 mm/day,-1.12 mm/day and 0.61 mm/day at Faisalabad, Lahore and Peshawar weather stations, respectively. Overall, Thornthwaite method gave better estimation of ETo than Penman ETo method at all the Weather stations.
VL  - 8
IS  - 5
ER  -

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