Real-time characteristics of tidal bore propagation in the Qiantang River Estuary, China, recorded by marine radar

摘要

Quantitative real-time observations of a tidal bore in a macro-tidal estuary are difficult and dangerous, particularly in large estuaries. Mathematical and numerical models have been used to predict tidal bore advances; however, to date, there have been no validations of large-scale flow patterns. A marine radar can provide valuable real-time information on tidal bore propagation. In this paper, a template matching method using a cross-correlation algorithm was explored to estimate the evolution and celerity of a tidal bore with medium resolution marine radar images. The Qiantang River tidal bore was recorded at two different geographical locations. Characteristic flow patterns were derived and analysed, including temporal changes over a relatively large-scale area. The experimental results showed that the radar-derived celerity and calculated height of the tidal bore were consistent with visual observations in this estuarine zone.