2019 FOSS4G Bucharest Talks speaker: Valentin Poncos
Multi-temporal Sentinel-1 based detection and mapping of changes of the ground properties induced by water content variations in Danube Delta
The Synthetic Aperture Radar (SAR) is the most suitable remote sensing technology to detect profound changes of the ground. The microwave frequency is able to penetrate the vegetation and the surficial level of the soil and evidentiate invisible information to the optical sensors and naked eye. In addition, the associated electromagnetic field is sensible to water content in vegetation and ground, making the SAR an effective water seeker. Water is the most important element that drives the changes in the natural environment; from the absence of it to flooding events the environment is adjusting and influences the ecology that depends on it, including the human habitats. The accurate measurement and mapping of the state of the ground requires a temporal dimension in order to build a suitable data stack to serve as input to a number of specific SAR-based techniques.
This work exploits the availability of large temporal datasets of dual-polarized Sentinel-1 data to extract information about water content on the ground (distinguishing between open surface water, flooded vegetation, water-saturated soil and dry ground) in Danube Delta, Romania. All the known SAR parameters (amplitude, polarization, interferometric coherence and phase)