Jiaonan tidal table

Tide table is the abbreviation of tide forecast table, which predicts the daily tide situation in some coastal areas in a certain period in the future.

Tidal phenomenon is a natural phenomenon in coastal areas, which refers to the periodic movement of seawater under the tidal force of celestial bodies. Traditionally, the vertical fluctuation of sea surface is called tide, and the horizontal flow of sea water is called tidal current. Our ancestors called the high tide in the morning and the high tide in the evening as high tide to indicate the moment of tide. This is the origin of the name Chao. The tidal table in Jiaonan is as follows:

05: 14 1 1: 26 17: 38 23: 50.

06: 02 00: 38 18: 26 12: 14.

Grade18 06: 5001:2619:1413: 02.

07: 38 02: 14 20: 02 13: 50.

08:26 03:02 20:50 14:38, grade 5, grade 20.

2 1, 09:14 03: 5021:3815: 26 on the 6th day.

The seventh day? 22 10: 02 04: 38 22: 26 16: 14

Grade 2310: 50 05: 26 23:1417: 02.

September 24th 00: 02 06:141:3817: 50.

00: 50 07: 0212: 2618: 38 on the fifth day of the tenth lunar month.

Eleven twenty-six 01:38 07: 5013:1419: 26

12 27 02: 26 08: 38 14: 02 20: 14

Thirteen twenty-eight 03:14 09: 2614: 50 21:02

14 29 04: 02 10: 14 15: 38 2 1: 50

15: 30 04: 5011:0216: 26 22: 38

The influence of tides on celestial bodies;

Tides and the slowdown of the earth's rotation

Due to the viscous force and the friction between sea water and land and seabed, tides have a braking effect on the earth's rotation, which gradually slows down the earth's rotation. Research shows that the earth's rotation period is extended by 1-2 milliseconds every hundred years. If this mitigation effect is applied to a long time span, the number of days in a year was about 400 days 370 million years ago (Devonian), which is related to Devonian.

The moon always faces us with the same face.

It is found that the moon always faces us in the same direction, and its other side is invisible to us on earth. This is because the period of the moon's rotation is exactly equal to the period of the moon's rotation around the earth, and the same two periods are the result of the long-term action of tides. According to the calculation, the tidal force of the earth to the moon is 22.438+07 times that of the moon to the earth. With such a powerful tidal force and the moon's moment of inertia much smaller than that of the earth, the slowdown of the moon's rotation speed caused by tides is particularly significant. It is conceivable that the early moon's rotation speed was very high, and under the action of tides, the moon's rotation gradually slowed down. Finally, the rotation period of the moon is equal to the rotation period of the moon around the earth. At this time, the tide of the moon disappears, and the rotation period of the moon no longer changes, so today's moon always faces the earth on the same side.

Tides and the increase of the distance between the moon and the earth

Tides slow down the earth's rotation, resulting in a decrease in the angular momentum of the earth's rotation. Because the total angular momentum of the Earth-January system should remain unchanged, and the direction of the moon's rotation around the Earth is basically the same as that of the Earth's rotation, the decrease of the angular momentum of the Earth's rotation will inevitably increase the angular momentum of the center of mass of the Moon-January system, thus maintaining the conservation of the total angular momentum of the Earth-January system. The actual effect of this effect is to slowly increase the distance between the moon and the earth. According to recent observations, the moon is moving away from the earth at a rate of 3.8 1 cm per year. The moon is slowly moving away from the earth, which can also be explained by the acceleration of the moon formed by the tidal uplift of the earth.

Because the convex part of the tide is brought to the east by the earth's rotation, the convex part A is closer to the moon than B, and the gravity of these two parts on the moon is different, which makes the center of gravity of the earth drift to the east of the connecting line between the center of mass of the earth and the moon. So the moon produces a small acceleration in the direction of its orbital motion, which accelerates the speed of the moon and slowly hovers outward.