Skip to main content
SpringerLink
Log in

An evaluation of common pan coefficient equations to estimate reference evapotranspiration in a subtropical climate (north of Iran)

  • Original Paper
  • Published:
Irrigation Science Aims and scope Submit manuscript

Abstract

Accurate reference evapotranspiration (ET0) data are essential to water resources project planning and farm irrigation scheduling. Evaporation pans are widely used to estimate reference ET0. Via the pan coefficient (K p), ET0 is estimated from evaporation pan data. Four common K p equations (Orang in Potential accuracy of the popular non-linear regression equations for estimating pan coefficient values in the original and FAO-24 tables, unpublished report, 1998; Allen and Pruitt in J Irrig Drain Eng 117(5):758–773, 1991; Cuenca in Irrigation system design: an engineering approach, p 133, 1989; Snyder in J Irrig Drain Eng 118(6):977–980, 1992) to calculate daily K p coefficients to estimate ET0 were evaluated using a 10-year mean climate dataset for a subtropical climate (north of Iran). Overall results showed that ET0 calculated using the daily K p values from Orang (Potential accuracy of the popular non-linear regression equations for estimating pan coefficient values in the original and FAO-24 tables, unpublished report, 1998) provided more accurate daily, monthly, and annual total estimates compared to the others equations.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5

Similar content being viewed by others

References

  • Allen RG, Pruitt WO (1991) FAO-24 reference evapotranspiration factors. J Irrig Drain Eng 117(5):758–773

    Article  Google Scholar 

  • Allen RG, Pereira LS, Raes D, Smith M (1998) Crop evapotranspiration. Guidelines for computing crop water requirements. Irrigation and drainage paper no. 56. FAO, Rome

    Google Scholar 

  • Cuenca RH (1989) Irrigation system design: an engineering approach. Prentice-Hall, Englewood Cliffs, p 133

  • Doorenbos J, Pruitt WO (1977) Guidelines for predicting crop water requirements. FAO irrigation and drainage paper 24. United Nations-Food and Agricultural Organization, Rome, p 34

    Google Scholar 

  • Frevert DK, Hill RW, Braaten BC (1983) Estimation of FAO evapotranspiration coefficients. J Irrig Drain Eng 109(2):265–270

    Article  Google Scholar 

  • Grismer ME, Orang M, Snyder R, Matyac R (2002) Pan evaporation to reference evapotranspiration conversion methods. J Irrig Drain Eng 180–184

  • Irmak S, Haman D, Jones W (2002) Evaluation of Class A pan coefficients for estimating reference evapotranspiration in humid location. J Irrig Drain Eng 128(3):153–159

    Article  Google Scholar 

  • Jensen ME (1974) Consumptive use of water and irrigation water requirements. Irrig. Drain. Div. Rep, vol 89. ASCE, New York, pp 15–41

  • Kosarev AN, Yablonskaya EA (1994) The Caspian Sea. SPB Academic Publishing, The Hague, p 274

  • Orang M (1998) Potential accuracy of the popular non-linear regression equations for estimating pan coefficient values in the original and FAO-24 tables. Unpublished Report, California Department of Water Resources, Sacramento, CA

  • Raghuwanshi NS, Wallender WW (1998) Converting from pan evaporation to evapotranspiration. J Irrig Drain Eng 118(6):977–980

    Google Scholar 

  • Rodionov SN (1994) Global and regional climate interaction: the Caspian Sea experience. Water science and technology library. Kluwer, Dordrecht, p 241

  • Snyder RL (1992) Equation for evaporation pan to evapotranspiration conversions. J Irrig Drain Eng 118(6):977–980

    Article  Google Scholar 

Download references

Acknowledgments

This study is the partial work of Project No. 7351023/1/02 supported by University of Tehran and was done in department of Irrigation and Drainage Engineering, Faculty of Agricultural Engineering, University College of Abourayhan. The meteorological data were provided from Iran Meteorological Organization.

Author information

Authors and Affiliations

  1. Irrigation and Drainage Engineering Department, Faculty of Agricultural Engineering, University College of Abourayhan, University of Tehran, Tehran, Iran

    Ali Rahimikhoob

Authors
  1. Ali Rahimikhoob
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Ali Rahimikhoob.

Additional information

Communicated by A. Kassam.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Rahimikhoob, A. An evaluation of common pan coefficient equations to estimate reference evapotranspiration in a subtropical climate (north of Iran). Irrig Sci 27, 289–296 (2009). https://doi.org/10.1007/s00271-009-0145-4

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00271-009-0145-4

Keywords

Search

Navigation