Tidevannssvingninger

Tidevannssvingninger, also known as tidal fluctuations or tidal ranges, refer to the difference in sea level between high tide and low tide. This phenomenon is primarily caused by the gravitational forces exerted by the Moon and the Sun on Earth's oceans. The Moon's gravitational pull is the dominant factor, creating bulges of water on both the side of the Earth facing the Moon and the opposite side. As the Earth rotates, coastal areas pass through these bulges, experiencing high tides. In between these bulges, the water level is lower, resulting in low tides.

The Sun also exerts a gravitational influence, though weaker than the Moon's. When the Sun, Moon, and Earth are aligned (during new and full moons), their combined gravitational forces lead to exceptionally high high tides and very low low tides, known as spring tides. Conversely, when the Sun and Moon are at right angles to each other relative to the Earth (during quarter moons), their gravitational pulls partially counteract each other, resulting in less extreme tidal ranges, called neap tides.

The magnitude of tidevannssvingninger varies significantly depending on geographical location, coastal shape, and ocean floor topography. Some areas experience very large tidal ranges, exceeding several meters, while others have much smaller fluctuations. These daily and semi-daily cycles of rising and falling sea levels are a fundamental aspect of coastal environments, influencing marine ecosystems, navigation, and human activities.