Most of the Earth’s surface lacks of reliable precipitation and temperature data from meteorological stations. There is a need of an alternative source of data , especially in developing countries with scarcity of hydrological resources. Meteorological data is needed for the hydrogeological studies required to build infrastructures (i.e. agriculture, civil, energetic, …), implement decontamination solutions, scientific studies, etc. That is why applying indirect methodologies such as satellite sensors, becomes a valuable tool which could enhance human development.
The key information required to elaborate quantitative hydrological analysis at a basin scale are the amount of water entering the system (precipitation), and the possible outlets (I.e. evaporation and transpiration), as well as their temporal and spatial variability. Meteorological stations provide local information and, therefore, the error of extrapolating data to the whole basin is added to the intrinsic error of the station. However, data inferred from satellite information can overcome this drawback by offering a greater resolution of precipitation and temperature data both in time and space. The advantages that remote satellite sensors can offer to water resources studies are: availability of complete, cost-effective, repetitive spatial and temporal precipitation and temperature digital data in remote zones, continuous control and calibration of the data acquiring systems, and an easy and quick application. The obtained results should be calibrated with hydro- and hydrogeological data and compared with other evaluation methods.
Two satellite products, the Tropical Rainfall Measuring Mission (TRMM) and the Atmospheric Infrared Sounder (AIRS), are used in this work. The accuracy of inferring precipitation values from these two products has been evaluated in three zones with different climatic regimes: Barcelona (Spain), El Salar de Atacama (Chile) and Pulán (Peru). Satellite estimates of precipitation and temperature have been verified against data collected from local meteorological stations. Finally, satellite information has been used to estimate the groundwater recharge in the Besòs basin, in the province of Barcelona (Spain).
In this work, we show that satellite derived meteorological data accurately reproduce the seasonal patterns in the three studied areas. It has been proven that satellite and climate models data are a reliable and valuable source of information for hydrological models. They are especially valuable in remote zones, and they constitute a good alternative for the improvement of the water resources management at a basin scale.