Evaluation of the Performance of some Evapotranspiration Models at a Tropical Location in Ile – Ife, Nigeria


  • Adekunle B. Toyeje Obafemi Awolowo University, Ile Ife, Nigeria
  • Lukman A. Sunmonu Obafemi Awolowo University, Ile Ife, Nigeria
  • Ayodele P. Olufemi University of Medical Sciences, Ondo, Ondo State, Nigeria
  • Oladimeji A. Babatunde Obafemi Awolowo University, Ile Ife, Nigeria
  • Olawale E. Abiye Obafemi Awolowo University, Ile Ife, Nigeria
  • Olanrewaju O. Soneye-Arogundade Obafemi Awolowo University, Ile Ife, Nigeria
  • Muritala A. Ayoola Obafemi Awolowo University, Ile Ife, Nigeria
  • Opeyemi R. Omokungbe Obafemi Awolowo University, Ile Ife, Nigeria
  • Omodara F. Obisesan Obafemi Awolowo University, Ile Ife, Nigeria




Evapotranspiration, Peaman-Monteith, Hagreaves-Samani, Makkink, Turc, FAO-24 Radiation


This study evaluates the performance of some evapotranspiration models at Ile – Ife (7o 33’ N, 4o 33’ E) Nigeria. This was to identify suitable evapotranspiration (ET) models at the study site and to provide useful information for standardizing evapotranspiration estimations at a tropical location. Meteorological parameters (wind speed, relative humidity, temperature, solar radiation, soil heat flux, and net radiation) were routinely measured at the Obafemi Awolowo University (OAU) Meteorological Station located within the Teaching and Research Farm of the campus for a period of a month (1st – 29th July 2014). Nine standardized models for the estimation of ET; Penman-Monteith (FAO-56 PM), Priestly-Taylor (PT), Makkink (MAKK), Jensen-Haise (JH), Hargreaves-Samani (HS), Ivanov (IVA), Modified Romanenko (MROM), FAO-24 Radiation (FAO-24 RAD) and Turc (TURC) models were employed. The ET values obtained from these models were then compared to the estimated values obtained from the FAO-56 PM equation recommended as the international standard method for determining reference ET. The estimation of the ET obtained from FAO – 56 PM model ranged between 0.426 – 2.239 mm/day, MAKK, JH, and HS gave estimation closest to this, ranging from 0.544 – 2.272 mm/day. The estimation of ET from other models revealed that PT has the highest value ranging between 1.323 – 6.936 mm/day, followed closely was FAO – 24 RAD with values ranging between 1.197 – 6.500 mm/day, values of IVA model ranged from 0.620 – 1.829 mm/day, MROM value ranged from 1.240 – 3.659 mm/day, TURC has the least value ranging from 0.190 – 0.584 mm/day. Using the result of the mean biased error and regression analysis, JH model compared best with the FAO – 56 PM with coefficient of determination (R2) = 0.927; slope (b) = 0.957; mean biased error (MBE) = 0.133, this was followed closely by HS with value R2 = 0.929; b = 1.199; MBE = - 0.075 and MAKK with the value R2 = 0.931; b = 1.198; MBE = - 0.052. However, the other models showed significant over or underestimation of the ET benchmark values. The performance of the other models showed no improvement after they were recalibrated by adjusting their original coefficients. Thus, six out of the ET models employed in this study [the Priestly-Taylor (PT), Makkink (MAKK), Jensen-Haise (JH), Hargreaves-Samani (HS), FAO-24 Radiation (FAO-24 RAD) and Turc (TURC)] were found suitable for the climatic region of Ile – Ife after the adjustment of their coefficients.

Author Biographies

Adekunle B. Toyeje, Obafemi Awolowo University, Ile Ife, Nigeria

Department of Physics and Egineering Physics and Lecturer

Lukman A. Sunmonu, Obafemi Awolowo University, Ile Ife, Nigeria

Department of Physics and Egineering Physics and Lecturer

Ayodele P. Olufemi, University of Medical Sciences, Ondo, Ondo State, Nigeria

Department of Physics and Lecturer

Oladimeji A. Babatunde, Obafemi Awolowo University, Ile Ife, Nigeria

Department of Physics and Egineering Physics and Lecturer

Olawale E. Abiye, Obafemi Awolowo University, Ile Ife, Nigeria

Centre for Energy Research and Development (CERD), Obafemi Awolowo University, Ile–Ife, 

Olanrewaju O. Soneye-Arogundade, Obafemi Awolowo University, Ile Ife, Nigeria

Department of Physics and Egineering Physics and Lecturer

Muritala A. Ayoola, Obafemi Awolowo University, Ile Ife, Nigeria

Department of Physics and Egineering Physics and Lecturer

Opeyemi R. Omokungbe, Obafemi Awolowo University, Ile Ife, Nigeria

Department of Physics and Egineering Physics and Lecturer

Omodara F. Obisesan, Obafemi Awolowo University, Ile Ife, Nigeria

Department of Physics and Egineering Physics and Lecturer


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How to Cite

Toyeje, A. B., Sunmonu, L. A., Olufemi, A. P., Babatunde, O. A., Abiye, O. E., Soneye-Arogundade, O. O., Ayoola, M. A., Omokungbe, O. R., & Obisesan, O. F. (2020). Evaluation of the Performance of some Evapotranspiration Models at a Tropical Location in Ile – Ife, Nigeria. Asian Journal of Applied Sciences, 8(6). https://doi.org/10.24203/ajas.v8i6.5854