A comparison of empirical equations of Estimating Potential Evapotranspiration (PET) from climatological data in Erbil city

Sardar.M.R.K Al-Jumur

doi:10.21271/ZJPAS.32.2.13

Authors

Sardar.M.R.K Al-Jumur Department of Physics, College of Science, Salahaddin University-Erbil, Kurdistan Region, Iraq

DOI:

https://doi.org/10.21271/ZJPAS.32.2.13

Keywords:

potential evapotranspiration , PET ,Pristley –Taylor(PT) , Turc(TU) Makkink (MK) , Ivanov (IV) , Penman–Monteith , FAO Penman–Monteith Thornthwaite(TW)

Abstract

Potential evapotranspiration (PET) is an important index of hydrologic budgets at different spatial scales and it is a critical variable for understanding regional hydrological processes. The objective of this study is to find the most suitable method for estimating PET in Erbil city which was done by comparing seven commonly PET methods. Radiation based method: Pristley –Taylor(PT), Turc(TU), Makkink (MK), and temperature based method: Ivanov (IV), Penman–Monteith method (1965) , FAO Penman–Monteith method, and Thornthwaite(TW). The data were collected and used in the models to find PET for the period (1992-2015). The performance indicators were applied by using statistical parameters such as: the Root Mean Square Error (RMSE), Mean Absolute Error (MAE), person correlation coefficient (R2), MBE Mean bias error. The monthly PET results from the models were compared with the actual evaporation. Current work shows that Makkink (MK) model is better than the other models for estimating the potential Evapotranspiration in Erbil depending on the values of statistical parameters.

References

Allen, R.G.; Pereira, L.S.; Raes, D. & Smith, M. (1998). Crop evapotranspiration – Guidelines for computing crop water requirements. FAO Irrigation and Drainage Paper, No. 56, FAO, Rome.

Abdullah, S.S., Malek, M., Mustapha, A. and Aryanfar, A. (2014) Hybrid of Artificial Neural Network-Genetic Algorithm for Prediction of Reference Evapotranspiration (ET?) in Arid and Semiarid Regions. Journal of Agricultural Science 6(3), p191.

Ahmed Saud, Md Azlin Md Said , Rozi Abdullah and Ammar Hatem.,2014. Temporal and Spatial variability of Potential Evapotranspiration in Semi-Arid Region: Case Study the Valleys of Western Region of Iraq.6(9), 0975-5462.

Anderson, M.C. Hain, C., Pimstein, A., Mecikalski, J. R., and Kustas, W. P.: Evaluation of Drought Indices Based on Thermal Remote Sensing of Evapotranspiration over the Continental United States. J. Climate, 24, 2025-2044, doi:10.1175/2010JCLI3812.1, 2011a.

Allen, R.G., Pereira, L.S., Raes, D., Smith, M. (1998): Crop evapotranspiration – Guidelines for computing crop water requirements – FAO Irrigation and drainage paper 56. Food and Agriculture Organization of the United Nations, Rome.

Bakhtiari. S. (2011). “Microfinance And Poverty Reduction: Some International Evidence”, International Business & Economics Research Journal (IBER), 5(12).

Bormann H, (2011) Sensitivity analysis of 18 different potential evapotranspiration models to observed climatic change at German climate stations. Climatic Change 104:729–753.

Efthimiou, K., Argalia, E., Kaskaba, E., & Makri, A. (2013). Economic crisis & mental health: What do we know about the current situation in Greece, 50, 22-30.

Efthimiou N, Alexandris S, Karavitis C, Mamassis N (2013) Comparative analysis of reference evapotranspiration estimation between various methods and the FAO56 penman-Monteith procedure. European Water Journal 42:19–34.

Federer, C.A., C. Vörösmarty, and B. Fekete, 1996. Intercomparison of Methods for Calculating Potential Evaporation in Regional and Global Water Balance Models. Water Resources Research 32:2315-2321.

Fennessey, N.M. and R.M. Vogel, 1996. Regional Models of Potential Evaporation and Reference ET for the Northeast USA. Journal of Hydrology 184:337-354.

Fennessey, N., Vogel, R.M., 1990. Regional flow-duration curves for ungauged sites in Massachusetts. J. Water Resour. Plan. Manag. 116 (4), 530–549.

Federer CA, Vörösmarty C, Fekete B (1996) Intercomparison of methods for calculating potential evaporation in regional and global water balance models. Water Resour Res 32(7):2315–2321.

Henderson, J. Vernon, Adam Storeygard, and David N. Weil. 2012. “Measuring Economic Growth from Outer Space: Dataset.” American EconomicReview.

Ibrahim, A., A. Gilerson, T. Harmel, A. Tonizzo, J. Chowdhary, and S. Ahmed, 2012: The relationship between upwelling underwater polarization and attenuation/absorption ratio. Opt.Express,23,25662-25680, doi:10.1364/OE.20.025662.

Jahanbani, H., El-Shafie, A.H. 2011 a comparison of empirical equations of estimating potential evapotranspiration ( PET) from climatological data in Erbil city, Paddy and Water Environmen, 9, Issu 2, June: 207-220.

Kijne,J.W.1974.DeterminingEvapotranspiration. In : Drainage Principles and Applications. Int. Inst. for Land Recl. and lmpr. Wageningen-The Netherlands. 111 : 53-1 11.

Lu, Jianbiao; Sun, Ge; McNulty, Steven G.; Amatya, Devendra. 2005. A comparison of six potential evapotranspiration methods for regional use in the Southeastern United States. Journal of American Water Resources Association. 41(3): 621-633.

Morton, Fl., 1983. Operational estimates of areal evapotranspiration and their significance to the science and practice of hydrology. 3. Hydrol., 66: 1 76.

MAKKINK, G.F. (1957); Testing the Penman formula by means of lysimeters. Journal of the Institution of Water Engineers and Scientists. Vol. 11. 277–288.

Monteith, J.L. 1965. Evaporation and environment. pp. 205-234. In G.E. Fogg (ed.) Symposium of the Society for Experimental Biology, The State and Movement of Water in Living Organisms, Vol. 19, Academic Press, Inc., NY.

Mokhele Edmond Moeletsi , Sue Walker b, Hamisai Hamandawana (2013), Comparison of the Hargreaves and Samani equation and the Thornthwaite equation for estimating dekadal evapotranspiration in the Free State Province, South Africa, Physics and Chemistry of the Earth 66 (2013) 4–15.

Peterson, T. C., V. S. Golubev, and P. Y. Groisman (1995), Evaporation losing its strength, Nature, 377, 687 – 688.

Priestley,C.H.B., and R.J. Taylor, 1972:on the assessment of surface heat flux and evaporation using large scale parameters.Mon.Wea.Rev., 100,81-92.

Sardar M.R. Kareem, Dilshad G.A. Ganjo, Janan J.Toma.2017. Physical and Chemical properties of rainwater and its suitability for drinking and irrigating in Erbil city. ZJPAS 29 (5); 39-50.

Sardar M. Rashed, Osama T. Al-Taai , Ali M. Al-Salihi.2017.Analysis Study of Meteorological Parameters and their Relationship with Some Concentration of Tropospheric Gases over Erbil City. ZJPAS 29 (s4); s227-s241.

Shakeel Ahmad Bhat, Bashir Pandit, Mehraj U. Din Dar, Rehana Jan, Shafat Khan and Khanday Mehraj. 2017. Statistical Comparison of Reference Evapotranspiration Methods: A Case Study from Srinagar in J&K.Int.J.Curr.Microbiol.App.Sci. 6(9): 3731-3737.doi:https://doi.org/10.20546/ijcmas.2017.609.460 .

Thornthwaite, C. W.: Report of the Committee on Transpiration and Evaporation, 1943–1944. Trans. Amer. Geophys. Union25, 683–693 (1944).

Zohary, M.(1950). The flora of Iraq and its phytogeographical sub division. Dept. Agri. Iraq. Publ. 31:1-201.