Effect of spatial resolution on remote sensing estimation of total evaporation in the uMngeni catchment, South Africa

• Published in: Journal of applied remote sensing 2015-10, Vol.9 (1), p.095997-095997
• Main Authors: Shoko, Cletah, Clark, David, Mengistu, Michael, Dube, Timothy, Bulcock, Hartley
• Format: Article
• Language: English
• ISSN: 1931-3195; 1931-3195
• DOI: 10.1117/1.JRS.9.095997

This study evaluated the effect of two readily available multispectral sensors: the newly launched 30 m spatial resolution Landsat 8 and the long-serving 1000 m moderate resolution imaging spectroradiometer (MODIS) datasets in the spatial representation of total evaporation in the heterogeneous uMngeni catchment, South Africa, using the surface energy balance system model. The results showed that sensor spatial resolution plays a critical role in the accurate estimation of energy fluxes and total evaporation across a heterogeneous catchment. Landsat 8 estimates showed better spatial representation of the biophysical parameters and total evaporation for different land cover types, due to the relatively higher spatial resolution compared to the coarse spatial resolution MODIS sensor. Moreover, MODIS failed to capture the spatial variations of total evaporation estimates across the catchment. Analysis of variance (ANOVA) results showed that MODIS-based total evaporation estimates did not show any significant differences across different land cover types (one-way ANOVA; F1.924=1.412, p=0.186). However, Landsat 8 images yielded significantly different estimates between different land cover types (one-way ANOVA; F1.993=5.185, p