Document Type : Original Article


1 Postgraduate in watershed management engineering, Payam Noor University part-time instructor, DehDasht branch, Kohkiloie Va Boirahmad, Iran

2 Postgraduate in watershed management engineering, Islamic azad university of Arsanjan branch, Arsanjan, Fars, Iran


Sensitivity analysis to determine variations in evapotranspiration is much important considering a known variation in one of climatic variables. In this study, sensitivity of evapotranspiration from Penmann-Mantith, Penmann-Kimberly (1996), Penman-Kimberly (1972) and Penmann (1984)  and Hargrivs (1985) approaches to three climatic variations (maximum temperature, wind speed, solar radiation) was studied in station Fasa for an interval of 22 years (1982-2003). In this research, in order to represent the effect of climatic variables on evapotranspiration, variation percentage standard was used. The results showed that, in most approaches, the most sensitivity was to net radiation, maximum temperature and wind speed, respectively. The results of this study are applicable for measurement of climatic variations in order to estimate evapotranspiration.


1- Tafazzoli, F., Sabziparvar, A. A., Zareabyane, H., Banezhad, H., Mousavibaygani, M. V. and Marijani, Z. 1386. Sensitivity of various evapotranspiration estimation models to weather parameters and global warming in semi-arid climate of Hamedan. 9th Irrigation and Evaporation reduction Seminar.Kerma.
2- Bayat, M. H., Zare, H., Sabziparvar, A. A. and Ghasemi, A. 1387. Evaluating sensitivity of various Ref-Et models to weather parameters (A case study, Tabriz).3rd conference of water resources management of Iran, Tabriz University.
3- Ambas, A.Th. andE.Baltas, 2011. Sensitivity analysis of different evapotranspiration methods with a new sensitivity coefficient, Proceedings of the 12th International conference on Environmental Science and Technology Rhodes, Greece, 46-53.
4- Babajimopoulos,Ch., Antonopoulos, B. Grigoriadis, D.andLLIas, A., 1992. Sensitivity analysis of the penman method, Proceeding of 5th conference of H.Y.U., P.132-140.
5- Beven, K., 1979. A sensitivity analysis of the Penman–Monteith actual evapotranspiration estimates. Journal of Hydrology 44, 169–190.
6- Coleman, G., DeCoursey, D.G., 1976. Sensitivity and model variance analysis applied to some evaporation and evapotranspiration models. Water Resource Research 12 (5), 873–879.
7- Goyal, R.K., 2004. sensitivity of evapotranspiration to global warming: a case study of arid zone of rajestan(India),Agri. Water . Mnage,69,1-11.
8- Gong Lebing, Chong-yuXu, Deliang Chen, Sven Halldin, Yongqin David Chen, 2006. Sensitivity of the Penman–Monteith reference evapotranspiration to key climatic variables in the Changjiang (Yangtze River) basin, Journal of Hydrology: 329, 620– 629.
9- Irmak Suat; José O. Payero; Derrel L. Martin; Ayse Irmak; and Terry A. Howell, 2006. Sensitivity Analyses and Sensitivity Coefficients of Standardized Daily ASCE-Penman-Monteith Equation, JOURNAL OF IRRIGATION AND DRAINAGE ENGINEERING, NOVEMBER-DECEMBER, 564- 578.
10- McCuen, R. H. ,1974.  A sensitivity and error analysis of procedures used for estimating evapotranspiration.  Water Resour. Bull., 10, 3,486–498.
11-Piper, B. S. ,(1989). Sensitivity of Penman estimates of evaporation to errors in input data. Agric. Water Manage., 15, 279–300.
12- Saxton, K. E. 1975. Sensitivity Analysis ofthe Combination EvapotranspirationEquation. Agric. Meterol., 15: 343-353.