Information about "Tide"

Tide is a natural phenomenon in coastal areas, which refers to the periodic movement of seawater under the tidal force of celestial bodies (mainly the moon and the sun).

Traditionally, the vertical fluctuation of sea surface is called tide, and the horizontal flow of sea water is called tidal current. In order to express the moment of tide, our ancestors called the climax in the morning and the climax in the evening sunseeker. This is the origin of the name Chao.

Tidal phenomenon: Tidal phenomenon is characterized by two climaxes every day and night, not once. "The sunrise is called tide, and the nighttime is called sunseeker". In short, "tide" refers to the rise of sea water during the day and "sunseeker" refers to the rise of sea water at night, but usually we often refer to both tide and sunseeker as "tide".

Because the earth and the moon are in constant motion, and the relative positions of the earth, the moon and the sun are changing periodically, the tidal force is also changing periodically, which makes the tidal phenomenon happen periodically.

In one day, except for the north and south poles and some areas, the tides in all parts of the earth fluctuate twice, each with a period of 12 hours and 25 minutes, twice a day, totaling 24 hours and 50 minutes, so the tide fluctuation time is delayed by 50 minutes every day. Most experienced people who live by the sea can calculate the time when the tide appears.