American Journal of Environmental Sciences

Comparison of Daily and Monthly Results of Three Evapotranspiration Models in Tropical Zone: A Case Study

Seyed Reza Saghravani, Sa Mustapha, Shaharin Ibrahim and Elias Randjbaran

DOI : 10.3844/ajessp.2009.698.705

American Journal of Environmental Sciences

Volume 5, Issue 6

Pages 698-705

Abstract

Problem statement: Evapotranspiration (ET) has crucial role in agricultural activity, water management and hydraulic engineering. Recently many forms of the equation have been applied for estimating daily and monthly evapotranspiration around the world. Approach: In this study, the daily and monthly ET was estimated by Penman, Penman-Monteith (P&M) and Hargreaves equation to evaluate general relationships for estimating monthly and daily values of these 3 methods and also effect of different parameters such as Humidity and wind speed on fluctuation of ET. Results: The results showed that maximum and minimum values were belonging to Hargreaves and P&M models, respectively. Conclusion: Statistical analysis showed significant difference among the three methods and coefficient variant for daily and monthly analysis was 18.49 and 7.17 respectively. However, the difference between mean value of P&M and Hargreaves, that has the most different, is 1 mm year-1.

Copyright

© 2009 Seyed Reza Saghravani, Sa Mustapha, Shaharin Ibrahim and Elias Randjbaran. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.