Hydrological monitoring of high-latitude shallow water bodies from high-resolution space-borne D-InSAR

Extensive high-latitude regions, such as northern deltaic ecosystems, are challenging to access due to remoteness and cold conditions during extended periods of the year. The hydro-ecological state of shallow water ecosystems can be influenced by anthropogenic activities (e.g., flow regulation, water abstraction) and climate variability/change. Therefore, they need to be monitored to provide baseline and impact data. In this paper, we capitalize on the water - vegetation interaction to evaluate relative water level variations on wetlands of one of the largest inland freshwater deltas in the world between the years 2012 and 2016 by exploiting RADARSAT-2 Synthetic Aperture Radar (SAR) and its differential interferometric configuration (D-InSAR). The influence of different terrain models on the topographic phase correction is also evaluated. Results revealed complex hydrodynamics in the water bodies studied and inferences of environmental processes taking place that modify local landforms and influence water level fluctuations. Comparison between D-InSAR derived water displacements and those measured at specific hydrometric stations indicates overall reliable results. The analysis proposed can be extended to study dynamics of deltaic lakes and wetlands in other areas of the globe.