Description
When a river mouth has a flat, converging shape and when the tidal range exceeds 6 to 9 m, the river may experience a tidal bore ([1,2,3]). A tidal bore is basically a series of waves propagating upstream as the tidal flow turns to rising. Hubert Chanson observed the tidal bore of the Sélune river, in the South-East of the Baie du Mont Saint Michel, France on 7 April 2004 when the tidal range exceeded 13 m [4,5]. The bore was first seen at Roche-Torin around 7:50 to 8:13am (Videos 1 and 2), and later at Pont Aubaud around 8:59am to 9:03 (Video 3).
This series of videos shows the Baie du Mont Saint Michel at sunrise before the arrival of the bore (Video 1), then the tidal bore at Roche-Torin, and at Pont Aubaud about 50 minutes later. The videos are associated with some technical details published in [4] and [5], and a series of photographs published in [6, 7, 8]. Two further websites on tidal bores are [7] and [8].