Characterization of complex fluvial systems using remote sensing of spatial and temporal water level variations in the Amazon, Congo, and Brahmaputra Rivers
Earth Surface Processes and Landforms
The Surface Water and Ocean Topography (SWOT) satellite mission will provide global, space-based estimates of water elevation, its temporal change, and its spatial slope in fl uvial environments, as well as across lakes, reservoirs, wetlands, and fl oodplains. This paper illustrates the utility of existing remote sensing measurements of water temporal changes and spatial slope to characterize two complex fl uvial environments. First, repeat-pass interferometric SAR measurements from the
... Earth Resources Satellite are used to compare and contrast fl oodplain processes in the Amazon and Congo River basins. Measurements of temporal water level changes over the two areas reveal clearly different hydraulic processes at work. The Amazon is highly interconnected by fl oodplain channels, resulting in complex fl ow patterns. In contrast, the Congo does not show similar fl oodplain channels and the fl ow patterns are not well defi ned and have diffuse boundaries. During inundation, the Amazon fl oodplain often shows sharp hydraulic changes across fl oodplain channels. The Congo, however, does not show similar sharp changes during either infi lling or evacuation. Second, Shuttle Radar Topography Mission measurements of water elevation are used to derive water slope over the braided Brahmaputra river system. In combination with in situ bathymetry measurements, water elevation and slope allow one to calculate discharge estimates within 2 . 3% accuracy. These two studies illustrate the utility of satellite-based measurements of water elevation for characterizing complex fl uvial environments, and highlight the potential of SWOT measurements for fl uvial hydrology.