Analyzing the relationship between meteorological changes and evapotranspiration trends in Gia Lai province, Central Highlands of Vietnam

Abstract

This study aims to analyze the historical trends of evapotranspiration at annual and seasonal scales and assess the sensitivity to various meteorological factors in Gia Lai province from 1980 to 2019. The modified innovative-Sȩn trend method and Sobol analysis are employed for trend identification and sensitivity assessment, respectively. The results obtained indicate significant downward trends using both the innovative-Sȩn trend analysis and the improved version of the innovative trend analysis method across different stations and time scales. Furthermore, in the low-value subgroups of the rainy season at Pleiku and An Khe stations, there were notable increasing trends with quantitative values of approximately 6%. Sensitivity analysis reveals that evapotranspiration is most sensitive to sunshine duration across most stations on annual and seasonal time scales, followed by relative humidity and minimum temperature. Overall, this research provides valuable insights into the relationship between evapotranspiration and relevant climate variables, contributing to the assessment of water demand for agricultural irrigation.