Spring Tide

A tide with the greatest difference between high and low water occurring when the Sun, Moon, and Earth are aligned during new and full moons.

A spring tide is a natural tidal phenomenon that occurs twice each lunar month during the new and full moon phases. It is characterised by the largest tidal range, the highest high tides and the lowest low tides. This occurs because the Moon and the Sun’s gravitational forces work in alignment when positioned in a straight line with the Earth, a configuration known as syzygy. The combined gravitational pull of these celestial bodies exerts a more potent force on Earth’s oceans, amplifying the tidal bulges. Despite its name, a spring tide is not related to the season spring; the term spring in this context derives from the Old English word “springan,” meaning to leap or rise.

Spring tides are significant for maritime activities, as they can influence navigation, anchorage, and harbour accessibility. For example, the higher high tides may allow larger vessels to navigate shallow channels during spring tides, while the lower low tides can expose hazards such as sandbanks or rocks. Additionally, the increased tidal currents associated with spring tides can affect vessel handling, requiring careful planning by mariners. Understanding the timing and magnitude of spring tides is essential for safe and efficient operations at sea.