Valentin Poncos, Owner and Geophysicist at Kepler Space Inc, discusses SAR/InSAR water extent mapping, mapping vegetation as water, and how water mapping changes in the wetlands.
The study area he is discussing is 532 hectares of wetland field and forest, near the Thousand Islands in Ontario. He began with fieldwork, to install leveloggers and barologgers in the water. He wanted to know: when water is a meter under vegetation, how do you map it as water? Or do you map it as forest, or as something else?
He considers the geometry of the double-bounce scattering mechanism, and SAR amplitude at a steep incidence angle, and later changes to the acquisition geometry to shallower angles, to enhance the double bounce effect in the reeds areas. Shallow incidence angles of the InSAR means the flooded forest cannot be detected. He showed a water level change map and explained it can be calibrated to the same level as Google Earth heights. He did analysis of hydraulic gradients and of the connectivity between distinct water bodies in the Buells Creek reservoir.
This presentation was a part of the LiDAR/SAR Wetland and Water Monitoring Workshop at the Alberta Terrestrial Imaging Centre in June of 2014.