tides vs. lunar phases

This is a graph of the height of the high and low tides versus the day they occurred on. We used the highest high and the lowest low. What we hoped to see here was the relationship between the height of the tides and the lunar phase. Our prediction was that the tides would be at their largest displacements around the full and new moons (Spring Tides), and at their least displacements around the first and third quarter moons (Neap Tides).

The data for the high tide shows a gradual increase around the time of the full moon, and a sharp decrease during the third quarter moon. Unfortunately, the results for the remainder of the cycle are not as apparent as we had thought they would be.

The data for the low tide follows our predictions fairly well. It makes a peak around the time of the full moon, decreases, then increases around the new moon and finally decreases again nearing the first quarter.

We believe that our prediction is correct, it is just difficult to show due to the number of variables in height of tides. The peaks and valleys are clear, though.

Tidal Data obtained from NOAA, Lunar Phase Data from CalSky.