Sensitivity analysis of a FAO penman monteith for potential evapotranspiration to climate change

Sensitivity of the fao penman-monteith (fpm) potential evapotranspiration (pet) model under tropical climates has been studied in the present study. a total of 17 meteorological stations covering peninsular malaysia starting from 1987-2003 were used as model inputs. a sensitivity analysis (sa) was carried out using the graphical method for temperature,wind speed and solar radiation within the possible range of ±20% with increments of 5%. from the comparison done on the sensitivity of pet to climatic change,the kuala krai station gave the highest percentage change in terms of temperature (±6%). the highest percentage change for wind speed (±2%) and solar radiation (±17%) were shown at the alor setar and kuala krai stations,respectively. the alor setar station had the lowest percentage change for temperature (±0.3%) and solar radiation (±9.9). the lowest percentage change of wind speed (± 0.2%) was observed at the kuala krai station. pet percentage changes have a positive correlation to the percentage change of all climatic variables except for the cameron highlands station. results revealed that solar radiation has the most significant effect on pet (±14%),followed by temperature (±4%) and wind speed (±1%). taken together,these results suggest that solar radiation plays an important role in estimating pet in peninsular malaysia. © 2017 penerbit utm press. all rights reserved.