Peak Power: The Science of Spring Tides

If the gravitational pull of the Sun and the Moon are to combine their strength, then they must be positioned along the same axis. If they are in a straight line, then their cumulative gravity creates the maximum pull known as spring tides.

If the name "spring" in this context refers to the water "springing forth" rather than the season, then these tides can happen in any month. If the alignment happens twice every 29.5 days, then spring tides occur year-round.

If the gravitational forces of the two largest celestial bodies are pulling in the same direction or opposite directions along a single line, then the water is stretched more than usual. If the water is stretched more, then the tidal range reaches its maximum.

If spring tides require the Sun, Earth, and Moon to be in a straight line (syzygy), then this can only happen when the Moon is between the Earth and Sun or when the Earth is between the Sun and Moon. If these positions represent the New and Full Moon phases, then those are the correct times.

If two forces are applied in the same direction or along the same line, then they add together. If the Sun's gravity and the Moon's gravity are both pulling on Earth's oceans at the same time, then the resulting force is a combined "Maximum Pull."

If the tidal bulge is at its largest due to combined gravity, then the high tide must be taller. If more water is pulled into the high tide bulges, then less water is left in the areas of low tide, making them lower than average.

If the Sun, Earth, and Moon line up perfectly, then the astronomical term for this event is syzygy. If syzygy results in the strongest gravitational pull on the oceans, then it creates spring tides.

If spring tides happen during the New Moon and the Full Moon, and if each of these phases occurs once in a lunar cycle, then the total number of spring tide events in about 30 days is two.

If the Moon is in its "New" phase, it is located between the Earth and the Sun. If both the Sun and Moon are on the same side, then their gravitational pulls are synchronized to create the massive bulges of spring tides.

If neap tides occur when the Sun and Moon are at right angles and pulling against each other, then they have a small range. If the opposite alignment occurs in a straight line, then the resulting spring tides have a much larger range.

If gravity pulls the Earth away from the water on the far side while pulling the water toward the Sun/Moon on the near side, then two bulges are created. If the force is stronger due to alignment, then both bulges reach their maximum size.

If a straight line is represented by an angle of 180 degrees, then an astronomical diagram showing this layout illustrates syzygy. If syzygy is the cause of these tides, then the diagram represents spring tides.

If the combined gravity of the Sun and Moon pulls more water into the high tide bulges, then the areas between the bulges are drained more than usual. If the water level is lower than the standard "zero" on a chart, then it is a minus tide.

If spring tides create the highest and lowest water levels, then people need to know when their property might flood or when the sea floor will be exposed for exploration.

If the Moon is much closer to Earth, then it has a much higher "gradient" or difference in pull from one side of the Earth to the other. If the Moon's tidal force is about twice as strong as the Sun's, then the Sun is the "assistant" in creating spring tides.

If the water appears to "leap" or rise much higher than during the rest of the month, then the name describes this action. If this happens during the maximum pull, then they are spring tides.

If gravity is the force and the bodies must work together to increase that force, then their positions relative to one another are the key. If they line up in a row, then they produce the maximum effect known as spring tides.

If the tidal range is maximized, then the water will reach its highest and lowest points of the month. If the high tide is exceptionally high, then it can push water into areas that normally stay dry, leading to flooding.

If the Sun is aligned with the Moon, it adds its gravitational strength to the tide. If it is millions of miles away, its total effect is smaller than the Moon's; however, it still provides the extra pull needed for spring tides.

If gravity provides the "pull," then inertia (the tendency of water to keep moving) provides the second bulge on the opposite side. If both gravity and inertia are required to explain the two bulges, then saying gravity is the "only" force is false.