Model details, parametrization, and accuracy in daily scale green roof hydrological conceptual simulation

In time, several models with different complexity have been proposed to predict the retention performances of a green roof. In the current study three conceptual models of increasing complexity in descriptive details, are calibrated and compared to experimental data. The proposed approaches consist of daily scale hydrological models, based on water balance equations, where the main processes and variables accounted for are the precipitation input, the evapotranspiration losses, and the maximum water storage capacity. Model detail increase is achieved moving from an approach using potential evapotranspiration and constant storage threshold to an approach using actual evapotranspiration and a variable storage threshold. The main findings confirm on one side the role played by evapotranspiration modeling and, on the other side, the good accuracy achieved, in a minimal calibration requirement approach, through the modeling of basic and elemental processes.