Estimation of actual evapotranspiration using SEBAL algorithm based on Landsat 8 imagery in Semarang area, Indonesia

Actual evapotranspiration (ET) is an important variable used for hydrological cycle analysis, drought monitoring, and water resources management. Field measurement of ET requires a lot of time, money and also produces non-spatial ET values. Satellite-based estimations give advantages to calculate evapotranspiration at a regional scale. This study aimed to assess the accuracy of estimated ET based on SEBAL using Landsat 8 imagery, and to determine the ET variation in relation with land cover in Semarang area. The analysis was carried out using Landsat-8 (OLI/TIRS) imagery recorded on April 24, 2020 and October 1, 2020, SRTM data and reference weather parameters. The estimated ET SEBAL was compared with Pan evaporation data, Penman-Monteith, and Advection Aridity. The study showed that the estimated ET errors between the ET estimates from SEBAL and Pan Evaporation, Penman-Monteith and Advection Aridity were less than or equal to 1.00 mm/day, but ET SEBAL estimate was not suitable in water bodies. Closed canopy vegetation had a higher ET value and metal rooftop had the lowest ET value. © 2023 Author(s).