(eng): With fast development of remote sensing technologies, demand for remote sensing data started to be increasing. Providing space resolution of these data may not be sufficient for target application. For that reason the methods for fusing remote sensing images were developed. This issue appears in the question of demand for high resolution thermal data. Sentinel-3 provides free remote sensing thermal data with space resolution 1000x1000 m, which may be insufficient for some specialized applications. In this thesis, standard methods of image fusion are presented as well as specialized methods for thermal sharpening, their modifications, implementation and results including validation and comparison.