Slope instabilities in alpine environments (i.e. in the altitudinal zones between the tree line and the upper limit of plant life) are caused by landslides and rockglaciers. In these regions global warming causes a decline of permafrost which results in increasing numbers of landslides. Therefore, an efficient survey of unstable slopes in these regions is required. Differential SAR interferometry is an emerging technique for the mapping of geophysical displacements at low cost and high resolution.

The objective of the ALPS project was to assess (in a service review phase) the potential user base, user requirements and algorithms to use ERS and ENVISAT ASAR data for the alpine landslide detection and monitoring, and to specify (in a service definition phase) related products and services and develop a detailed system architecture for the implementation of the service.