Effects of spatial aggregation on the multi-scale estimation of evapotranspiration

► Effects of input and flux aggregation on SEBS evapotranspiration are examined. ► Input aggregation reduces SEBS evapotranspiration at image scale by up to 15%. ► Input aggregation reduces SEBS evapotranspiration at pixel scale by up to 50%. ► Main reason for ET reduction by input aggregation is due to roughness parameters. ► In flux aggregation, a simple averaging scheme is the best choice.