Evapotranspiration Estimation with the S-SEBI Method from Landsat 8 Data against Lysimeter Measurements at the Barrax Site, Spain

Abstract

Evapotranspiration (ET) is a variable of the climatic system and hydrological cycle that plays an important role in biosphere–atmosphere–hydrosphere interactions. In this paper, remote sensing-based ET estimates with the simplified surface energy balance index (S-SEBI) model using Landsat 8 data were compared with in situ lysimeter measurements for different land covers (Grass, Wheat, Barley, and Vineyard) at the Barrax site, Spain, for the period 2014–2018. Daily estimates produced superior performance than hourly estimates in all the land covers, with an average difference of 12% and 15% for daily and hourly ET estimates, respectively. Grass and Vineyard showed the best performance, with an RMSE of 0.10 mm/h and 0.09 mm/h and 1.11 mm/day and 0.63 mm/day, respectively. Thus, the S-SEBI model is able to retrieve ET from Landsat 8 data with an average RMSE for daily ET of 0.86 mm/day. Some model uncertainties were also analyzed, and we concluded that the overpass of the Landsat missions represents neither the maximum daily ET nor the average daily ET, which contributes to an increase in errors in the estimated ET. However, the S-SEBI model can be used to operationally retrieve ET from agriculture sites with good accuracy and sufficient variation between pixels, thus being a suitable option to be adopted into operational ET remote sensing programs for irrigation scheduling or other purposes.

Evapotranspiration Retrieval Using S-SEBI Model with Landsat-8 Split-Window Land Surface Temperature Products over Two European Agricultural Crops

“…Finally, it has to be mentioned that our results, using the S-SEBI model and LST data retrieved with an SW algorithm applied on TIRS data at the two cropland sites, were in good agreement with those obtained in the previous eight related studies [6][7][8][9][10][11][12][13]. This fact showed also the good performance of the S-SEBI model, together with the reliability of the use of Landsat-8 SW-LST data, over European agricultural sites.…”

“…Six out of these eight studies tested the S-SEBI ET algorithm, introducing as input the LST retrieved from Landsat-8 with a single-channel method [5], at crop sites located in the USA [6,7] and Asia [8][9][10][11]. The last two references used a split-window (SW) algorithm to estimate LST, and later the S-SEBI model to obtain the ET on natural grasslands in Brazil, and a cropland in Spain [12,13].…”

Performance evaluation of Satellite-based actual evapotranspiration technique

“…The S-SEBI is a remote sensing energy balance model to estimate surface energy fluxes from remote sensing measurements (Basit et al, 2018) Eq. 1 where λ = latent heat of vaporization (J/kg), Λ = evaporative fraction, and ρ w = the density of water (kg/m 3 ) and R n is the net radiation flux (Wm −2 ).On the other hand, R n was adopted from Sobrino et al (2021)…”

Spatial-Temporal Variation in Paddy Evapotranspiration in Subtropical Climate Regions Based on the SEBAL Model: A Case Study of the Ganfu Plain Irrigation System, Southern China

“…With the continuous development of remote sensing (RS) technology in recent decades [7][8][9], satellite sensors with multiple spatial, temporal, and spectral resolutions (e.g., Land Remote Sensing Satellite (Landsat), Moderate Resolution Imaging Spectroradiometer (MODIS), Advanced Very-High-Resolution Radiometer (AVHRR), and Sentinel) have become ideal tools for estimating ET at a regional scale [10][11][12][13]. Various models have been reported for estimating ET with RS datasets [14][15][16].…”