Analisi di mappature termiche di acque costiere e corsi d’acqua ottenute da immagini ASTER

The ASTER sensor is, currently, the main radiometer that acquires information in the Thermal Infrared (TIR) region with a spatial resolution of 90 m. The purpose of this work is to develop a working methodology for the analysis of water temperature obtained from ASTER images. Images were initially processed with an algorithm that improves spatial resolution from 90 m to 30 m using information drawn from the Visibile-Near infrared (VNIR) ASTER bands. Then data were analyzed and classified with an object-oriented approach. Specific procedures were developed in order to automate the monitoring process and to better interpret and display water temperature of the analyzed images. The studies were performed both on images at 90 m and at 30 m (computed with the algorithm for improving the spatial resolution). In this way it was possible to test the effectiveness and validity of the algorithm. For example, watercourses in the image at 90 m were barely visible while in the image at 30 m can be easily analyzed. This study is not concluded: the procedures will be soon applied to a wider range of case studies. Thus it will be possible to verify the versatility of the procedures themselves, and the advantages from the use of the algorithm for improving the spatial resolution.