Tides
04: Tides
Applied Earth-Moon physics, and the module where you meet a model that fails.
Nothing in this module is safe for navigation. It is a teaching model. For anything that matters, use your national hydrographic office.
Lessons
| # | Lesson | What you get |
|---|---|---|
| 1 | What causes tides | The two-bulge model, built properly |
| 2 | The lunar day | Why tide times march forward ~50 min/day |
| 3 | Spring and neap | Predicting tidal range from Moon phase |
| 4 | Predict → Check → Explain | The core lab |
| 5 | Why local tides are hard | Where the model gives up |
Prerequisites
Modules 01, 02 and 03. You need to be comfortable with the lunar day and the Sun-Earth-Moon geometry.
No coast nearby?
Not a problem. Lesson 4 supplies datasets from real tide stations around the world, in docs/04-tides/data/. You can run the whole lab against Brest, Hilo, Fremantle or the Bay of Fundy without leaving your desk.
If you do live near tidal water, use your own station; it is much better.
Why this module matters more than it looks
Most of this curriculum builds models that work. This one builds a model that is physically correct and practically useless, and then works out why.
That is not a detour. Knowing that a model can be right about the physics and wrong about your harbour (and being able to say precisely which part is missing) is one of the most transferable things here. It is the difference between using a model and understanding one.
By the end you will have calibrated a physical model against real measurements, which is, in miniature, exactly what an operational tide service does.