Evaluation of the Regional-Scale Gash Model for Forest Interception Loss

Código

XXV-SBRH1259

Autores

Sabrina Holanda Oliveira, John Elton de Brito Leite Cunha, Fernanda Maria dos Reis Torroaes Valente

Tema

12 - Geotecnologias (Sensoreamento remoto e Geoprocessamento) Aplicada aos Recursos Hídricos

Resumo

An accurate estimate of rainfall interception loss is crucial for modeling the water balance in forested areas. However, considerable regional variability exists in the interception process, and much uncertainty remains. This study presents an advanced approach that enhances the estimation of rainfall interception loss at the regional scale by integrating remote sensing products into the parameterization of the Gash analytical model (RS-Gash). High-resolution satellite imagery was used to derive vegetation indices and spectral reflectance, which were then employed in linear regression models to estimate vegetation water storage capacity (Sv) and canopy cover fraction (c). These parameters hold significant importance in ecological processes, land management, and water resource management. Furthermore, the integration of MWSEP and ERA5-Land meteorological products facilitates the determination of mean rainfall and evaporation rates under canopy saturation conditions, the other two parameters required to run the model. Modeling performance was evaluated using in-situ measurements and gridded datasets. The findings demonstrate the considerable potential of this approach to enhance the accuracy of rainfall interception loss estimates while concurrently reducing the temporal and financial costs associated with data acquisition.