Authors: Dinuke Munasinghe – California Institute of Technology – Jet Propulsion Lab
Title: An Algorithm for Extraction of River Width from Harmonized Multi-platform Spaceborne Sensors
Abstract: Accurate estimates of river width information are important to understand and model the timing of flood waves reaching downstream river reaches/floodplains; to improve predictions of flooding location and extent as well as the distribution of flood storage over the watershed in hydraulic models; and in general, to provide surface water intelligence assessments of a nation. Harmonized products derived through multi-platform spaceborne sensors provide an opportunity for high-frequency width extractions with global coverage. We used provisional OPERA (Observational Products for End-users from Remote-sensing Analysis) Level-3 Dynamic Surface Water Extent (DSWx) from Harmonized Landsat-8 and Sentinel-2A/B (HLS) as the primary image input to evaluate a novel algorithm to extract river width. The algorithm is based on mapping river water pixels to each closest node from a set of equidistant nodes that are located on a river centerline. This study (a) provides insights on the potential of the DSWx-HLSfor river width extraction (b) demonstrates the capabilities of the river width extraction algorithm through use cases on hydrologically significant global river locations, and (c) provides useful baselines and guidance regarding constrains and applicability of the algorithm.