The monitoring of endangered slopes is one possible measure for providing protection against landslides. The FOEN uses the very latest methods for monitoring slopes, for example radar interferometry. This enables the identification of sliding masses and the magnitude of the sliding motion.
Observation of the following factors is necessary for the comprehensive monitoring of endangered slopes:
- Meteorological situation
Persistent and heavy rain is the main triggering mechanism for slope processes. For this reason, it is important to take the meteorological situation into account in the monitoring of endangered slopes.
- Hydrological situation
The volumes of precipitation that have already fallen and the groundwater level provide information about the possible destabilisation of an endangered slope.
- Terrain movements
The development of sliding velocities can be monitored through measurements. In addition to traditional measurement methods, increasingly sophisticated satellite-based methods, e.g. distance measurement using radar interferometry, are being developed.
With this method, satellites transmit radar waves to the Earth's surface which are then reflected there. This enables the very accurate measurement of the distance between the satellite and the Earth's surface. If a slope is moving, the distance between the satellite and the Earth's surface differs from one measurement period to the next. The measurement devices identify this difference and record it on the satellite images.
This method offers new possibilities for slope monitoring in unpopulated areas where no other measuring networks exist. Hence, radar interferometry is suitable, inter alia, for the monitoring of slopes that were previously stabilised by permafrost, which is now thawing due to climate change and causing the slope to move. However, the data are particularly suitable for use in combination with geomorphological information.
Last modification 05.11.2018