Abstract
This study quantifies evaporation and its impact on water resources in the Ebro River basin. The basin exhibits an uneven distribution of precipitation. Runoff is mostly generated on the Pyrenean relief, however these water resources are mostly used in the valley, for agricultural purposes, necessitating the transportation and storage of water from the Pyrenean slopes to the central valley by means of a complex network of dams and canals. The expansion of forests in non-agricultural areas, resulting from the abandonment of unmechanized agricultural lands, has further increased water consumption. Thus, the forest is competing with agriculture for water availability. To address these challenges, this study aims to estimate actual evaporation at fine temporal and spatial scales using remote sensing and modelling datasets, with the aim to improve the estimation of water use and help the basin managers to make better decisions.
The research consists of two main stages. Firstly, the GLEAM and Sen-ET products are compared to identify similarities and differences in space (such as rainfed vs irrigated areas, agricultural vs natural areas, and forests) and time (including seasonal variations, irrigation vs non-irrigation periods, and wet vs dry periods). Secondly, the evaporation products based on satellite data are compared with the SASER hydrometeorological modelling output, based on the SURFEX LSM, at a spatial resolution of 1 km. The objective is to assess the agreement between models and remote sensing datasets and identify potential sources of uncertainty, particularly related to irrigation and forests water use.
The outcomes of this research will contribute to a better understanding of actual evaporation patterns and their implications for water use and availability in the Ebro River basin. The findings will aid water managers to improve the estimation of evapotranspiration at different temporal and spatial scales, facilitating more efficient and sustainable water resource management practices.