I have been on holiday to Brittany a few times and I was aware the tides there were enormous – but, when I looked into why, I discovered that the reality is even more fascinating and complex than O’Reilly failed to grasp.
Tides around the world can range from almost nothing to over ten metres – so how can the Moon’s gravity alone give rise to such a diversity of tides?
Well, it can’t – at least, not on its own. The Moon’s gravity is strong enough to cause Earth’s oceans to oscillate, but it can’t account for the the variety of tidal ranges observed. These variations are caused in large part by the physics of waves.
You can think of tides as enormous waves rolling around the circumference of the Earth. The interplay between these gargantuan oscillations, rebounding from continents and interacting with one-another, can allow for huge differences between local tides. The large tidal range in Brittany, for example, is due to a tidal resonance – the cumulative effect of adjacent tidal waves perfectly in sync. If you want to learn more, it’s explained in this video:
Read more at: Phys.org