The Sense of an Ending contains several mentions of the Severn Bore, a natural phenomenon Tony and Veronica witness one night when in university. The tidal bore is a wave that travels up the River Severn, moving against the current and appearing to push water backward—an image Tony associates with time moving in reverse.
The Severn Bore is formed by dramatic fluctuations in the 43-foot tidal range of the Severn Estuary, a coastal body of brackish water that empties into the Bristol Channel. As the rising tide floods into the estuary, surging water creates a series of waves that travel upstream at speeds between eight and thirteen miles per hour. While the tallest bores happen close to equinoxes, approximately 260 bores occur per year. Because phases of the moon affect tides, the largest bores follow several days after full or new moons. In October 1966, the tallest Severn Bore ever recorded measured 9.2 feet.
By no means the only tidal bore in the world, the Severn Bore is among the best known. Many spots along the public paths lining the riverbanks are considered ideal for witnessing the phenomenon. The Severn Bore also attracts surfers, who wait in the river hoping to catch a wave and see how far upstream they can travel.
