Spaceborne detection of forest disturbances - monitoring based on Sentinel-1 SAR data
Christian Ginzler
Andrea Manconi
Marius Rüetschi
Lars Waser
Dominique Weber
2023 - 2025
Spaceborne remote sensing enables large-scale monitoring of the forest to obtain information about occurring disturbances. Methods based on optical satellite data have the advantage that they are very intuitive and the data is very easy to interpret. The disadvantage is that no images of the earth's surface can be taken when there are clouds. For example, after the winter storm ‘Burglind’ (2 and 3 January 2018), no cloud-free and well-illuminated optical Sentinel-2 images of many disturbed areas were available for three months. The Sentinel-1 satellite constellation provides SAR data, which is recorded in the microwave domain regardless of cloud cover and is therefore available more continuously.
In the framework of this project, a system for detecting disturbances in forests is being developed on the basis of these SAR data and various test areas in Europe. By using the entire S1 constellation, a high temporal update rate is possible with data acquisition at least every three days. Based on the acquired SAR data, time series are created on the spatial scale of forest stands. The changes in the forest caused by disturbances are to be detected in the SAR data by means of time series analysis. It will be investigated 1) how quickly which types of disturbances and 2) on which spatial scale these disturbances can be detected.