The phenomenon of two high tides each day is a result of the gravitational interaction between the Moon, the Earth, and the Sun. Although the Moon takes approximately 27.3 days to complete one orbit around the Earth, it doesn't mean there is only one high tide per lunar day.
Here's a simplified explanation of the tidal mechanism:
Gravitational Force: Both the Moon and the Sun exert gravitational forces on the Earth. The Moon's gravitational force is stronger due to its proximity.
Moon's Influence: The Moon's gravitational force causes a bulge on the side of the Earth closest to the Moon. This creates a high tide in that area, known as the lunar high tide.
Opposite Side Bulge: At the same time, there is another high tide on the opposite side of the Earth, away from the Moon. This occurs due to the centrifugal force generated by the Earth-Moon system's rotation around their common center of mass.
Resulting Tides: As the Earth rotates, different parts of the planet experience these tidal bulges as they pass through them, resulting in two high tides and two low tides approximately every 24 hours.
It's important to note that the actual timing of the tides can be influenced by various factors, such as the specific geography of the coastline, the shape of ocean basins, and local factors like wind patterns and underwater topography. These factors can cause variations in the timing and height of tides in different locations.