Remote sensing techniques in landslide mapping and monitoring, keynote lecture

The current availability of highly developed remote sensing technologies in the field of landslide detection, mapping and monitoring allows for rapid and easily updatable data acquisitions, improving the traditional investigation capabilities, even in hazardous or inaccessible areas, while granting at the same time the safety of the operators during the fieldwork. In this work various application of remote sensing techniques for landslide detection, mapping and early warning, from spaceborne to ground-based platforms are described. Among earth observation (EO) techniques in the last decades optical and radar images are very effective tools for these implementations, since very high spatial resolution can be obtained by means of optical systems (currently in the order of magnitude of tens of centimeters), and by the new generations of synthetic aperture radar (SAR) sensors designed for interferometric applications, with revisiting times of few days. At the same time in the recent years, ground-based remote sensing techniques have undergone a significant increase of usage, thanks to their technological development and quality data improvement, in terms of spatial resolution and accuracy, fast measurement and processing times, portability and cost-effectiveness of the acquiring instruments. In this paper, the potential of space-borne imaging techniques, ground-based remote sensing methods and the effectiveness of their synergic use in the field of landslide analysis is explored by reviewing their state of the art, and by analyzing various case studies, characterized by different slope instability processes, spatial scales and emergency management phases. After assessing the advantages and limitations of the proposed methods, further fields of applications are evaluated.