macro-tidal coast

Macro-tidal coasts are defined by a large tidal range, typically exceeding four meters. These coasts are shaped by the significant rise and fall of sea level, which influences both sediment transport and the distribution of wave energy.1

Tidal currents on macro-tidal coasts can be powerful, especially in constricted areas like inlets, where they can erode bedrock and move large quantities of sediment. Along open coasts, the daily tidal cycle moves the shoreline, altering the zone where waves and currents can act. On gently sloping beaches or tidal flats, this can result in a shoreline shift of up to a kilometer during a tidal cycle.1

While micro-tidal coasts (less than two meters tidal range) are most common globally, macro-tidal coasts are also widespread and are characterized by features shaped primarily by tidal processes, often in contrast to wave-dominated coasts.12