The Sun's Interaction with the Tides. Spring Tides. Spring tides are especially strong tides (they do not have anything to do with the season Spring). They occur when the Earth, the Sun, and the Moon are in a line. The gravitational forces of the Moon and the Sun both contribute to the tides. Spring tides occur during the full moon and the new moon. The Proxigean Spring Tide is a rare, unusually high tide.