Conscientia Beam || conscientiabeam.com

Export to

Citations

Contact Us

For Marketing, Sales and Subscriptions Inquiries

2637 E Atlantic Blvd #43110
Pompano Beach, FL 33062

USA

Conference List

Current Research in Agricultural Sciences

December 2020, Volume 7, 2, pp 58-63

Reference Evapotranspiration by Hargreaves and Modified Hargreaves Equations under Semi-Arid Environment

Muhammad Hafeez

Zia Ahmad Chatha

Allah Bakhsh

Abdul Basit

Alamgir Akhtar Khan

Fatima Tahira

Muhammad Hafeez¹

Zia Ahmad Chatha²

Allah Bakhsh³ Abdul Basit³ Alamgir Akhtar Khan⁵
Fatima Tahira⁶

Department of Agricultural Engineering, Faculty of Agricultural sciences and Technology, Bahauddin Zakariya University, Multan, Pakistan. ¹

Department of Food Engineering, Faculty of Agricultural Engineering, University of Agriculture, Faisalabad, Pakistan. ²

Department of Botany, Ghazi University, Dera Ghazi Khan, Pakistan. ³

Department of Agricultural Engineering, MNSUA, Multan, Pakistan. ⁵

Department of Mathematics, Institute of Southern Punjab, Multan, Pakistan. ⁶

on Google Scholar

on PubMed

Pages: 58-63

DOI: 10.18488/journal.68.2020.72.58.63

Article History:

Received: 20 April, 2020
Revised: 03 June, 2020
Accepted: 28 September, 2020
Published: 17 November, 2020

View Citation

122Views

Create Citation Alert

Abstract:

The Penman-Monteith (FAO-56 PM) ETo equation is considered as the standard ETo equation to estimate reference evapotranspiration (ETo) under all the weather conditions of the world. But there are many regions of the globe where all the climatic data is not available to evaluate FAO-56 PM ETo equation. So, Hargreaves (HG) ETo equation can be used which required very small number of weather data. The HG ETo equation requires only air temperature as input data which is available at most of the weather stations of the world. But the major drawback of HG ETo equation is that it overestimates or underestimates FAO-56 PM ETo equation. So it becomes necessary to modify HG ETo Equation according to the local climatic conditions before it is being applied. The HGorg and modified HG ETo equations are assessed for ETo estimation under cold and hot semi-arid climatic conditions of Quetta and Zhob weather stations by using 9 years meteorological data of each weather station against FAO-56PM ETo equation. The original HG ETo equation overestimates FAO-56 PM ETo equation at Zhob weather station by giving percentage error of 15.82% and underestimate at Quetta weather station by giving percentage error of 35.02%. The coefficient of original HG ETo equation was modified by using a simple mathematical logic. The overestimation at Zhob weather station reduced to 1.89% and underestimation at Quetta station reduced to 0.87% by using modified HG ETo equation. The variations of original HG ETo equation with FAO-56 PM ETo equation has RMSE of 0.89 mm/day at Zhob weather station and 1.74 mm/day at Quetta weather station. The variations of modified HG ETo equation with FAO-56 PM ETo equation has RMSE of 0.27 mm/day at Zhob weather station and 0.29 mm/day at Quetta weather station.

Contribution/ Originality
The objective of this research is to modify the Hargreaves (HG) ETo equation according to the regional semi-arid conditions of Quetta and Zhob weather stations of Baluchistan Province.

Keywords:

Hargreaves equation, Calibrated Hargreaves equation, FAO-56 equation, Reference evapotranspiration, Semi-arid, Environment.

Reference:

[1] H. Muhammad, A. C. Zia, A. K. Alamgir, B. Allah, B. Abdul, and T. Fatima, "Estimating reference evapotranspiration by hargreaves and Blaney-Criddle methods in humid subtropical conditions," Current Research in Agricultural Sciences, vol. 7, pp. 15-22, 2020. Available at: 10.18488/journal.68.2020.71.15.22.

[2] Z. A. Chatha, M. Arshad, A. Bakhah, and A. Shakoor, "Statistical analysis for lining the watercourses," Journal of Agricultural Research, vol. 53, pp. 109-118, 2015.

[3] R. G. Allen, L. S. Pereira, D. Raes, and M. Smith, Crop evapotranspiration-guidelines for computing crop water requirements-fao irrigation and drainage paper 56. Rome: FAO, 1998.

[4] L. Feng, T. Li, and W. Yu, "Cause of severe droughts in southwest china during 1951–2010," Climate Dynamics, vol. 43, pp. 2033-2042, 2014. Available at: https://doi.org/10.1007/s00382-013-2026-z.

[5] H. Muhammad, B. Allah, B. Abdul, A. C. Zia, A. K. Alamgir, A. M. Muhammad, and T. Fatima, "Penman and thornwait equations for estimating reference evapotranspiration under semi-arid environment," Current Research in Agricultural Sciences, vol. 7, pp. 6-14, 2020. Available at: 10.18488/journal.68.2020.71.6.14.

[6] A. Berti, G. Tardivo, A. Chiaudani, F. Rech, and M. Borin, "Assessing reference evapotranspiration by the hargreaves method in north-eastern italy," Agricultural Water Management, vol. 140, pp. 20-25, 2014. Available at: https://doi.org/10.1016/j.agwat.2014.03.015.

[7] M. Hafeez and A. A. Khan, "Assessment of Hargreaves and Blaney-Criddle methods to estimate reference evapotranspiration under coastal conditions," American Journal of Science, Engineering and Technology, vol. 3, pp. 65-72, 2018.

[8] R. Bachour, W. R. Walker, A. F. Torres-Rua, and M. McKee, "Assessment of reference evapotranspiration by the hargreaves method in the bekaa valley, lebanon," Journal of Irrigation and Drainage Engineering, vol. 139, pp. 933-938, 2013. Available at: https://doi.org/10.1061/(asce)ir.1943-4774.0000646.

[9] G. H. Hargreaves and R. G. Allen, "History and evaluation of Hargreaves evapotranspiration equation," Journal of Irrigation and Drainage Engineering, vol. 129, pp. 53-63, 2003. Available at: https://doi.org/10.1061/(asce)0733-9437(2004)130:5(447.2).

[10] H. R. Fooladmand, H. Zandilak, and M. H. Ravanan, "Comparison of different types of Hargreaves equation for estimating monthly evapotranspiration in the south of Iran," Archives of Agronomy and Soil Science, vol. 54, pp. 321-330, 2008. Available at: https://doi.org/10.1080/03650340701793603.

[11] S. Gough and W. Scott, Higher education and sustainable development: Paradox and possibility. London: Routledge, 2007.

[12] G. H. Hargreaves and Z. A. Samani, "Reference crop evapotranspiration from temperature," Applied Engineering in Agriculture, vol. 1, pp. 96-99, 1985. Available at: https://doi.org/10.13031/2013.26773.

[13] A. Majeed, S. Mehmood, K. Sarwar, G. Nabi, and M. A. Kharal, "Assessment of Reference Evapotranspiration by the Hargreaves Method in Southern Punjab Pakistan," European Journal of Advances in Engineering and Technology, vol. 4, pp. 64-70, 2017.