What is the time law of high tide and low tide in the sea?

The vastness of the sea is desirable. Even if you have never seen the sea, many people know the phenomenon of its ebb and flow, which makes people feel amazing. Then, why does the sea ebb and flow? What is the time law of high tide and low tide? The following small series will bring an introduction.

Why does the sea ebb and flow

Xiao Bian answers the questions from the following aspects:

First of all, most of the earth we live in is made up of oceans. Among them, the capacity of seawater is about 1386 trillion cubic meters.

Of course, there was no ocean at first, because the earth was formed by the combination of large dust in the universe for a long time. The reason why a large area of seawater appeared behind is that the early earth was close to the sun, and under the action of temperature change, the water vapor in the atmosphere precipitated after chemical reaction, eventually forming a large ocean.

In the ocean, influenced by various factors, various strange phenomena often appear. For example, under special circumstances, there will be natural disasters such as tsunami, typhoon and storm surge.

in addition to natural disasters, there are also phenomena of high tide and low tide of seawater. For the occurrence of natural disasters, human scientists have made explanations, some of which are caused by weather changes and some are caused by human actions. However, the appearance of high tide and low tide of seawater is caused by the gravity of the sun and the moon.

The so-called high tide and low tide of seawater mean that the seawater rises or falls in a large area in a certain period of time, and the changes of the two are called tides.

due to the differences in mass and volume among the earth, the moon and the sun, the gravitational force generated is also different. The earth can move around the sun because the sun's gravity is greater than the earth's, so it can hold the earth firmly. The same is true of the moon orbiting the earth. Under the action of force between them, it will lead to internal changes, which will lead to the emergence of high tide and low tide of seawater.

let's talk about the formation of high tide and low tide. Under the gravitational pull of the sun and the moon, the sea water will continue to rise, and the area where the sea water rises the most is the closest place to the sun and the moon.

The ebb tide is actually called ebb tide because most of the sea water flows to the place near the sun or the moon, which leads to the distant sea water flowing to the lower place under the action of the internal force of the earth.

Secondly, high tide and low tide appear in the ocean, which will occur at different locations. Because the earth revolves around the sun, and the moon revolves around the earth, and the earth and the moon themselves are rotating. This has also led to the fact that when the earth is running, there will be differences in the gravity of local oceans, which will lead to different phenomena in the ups and downs.

finally, when the tide is high, we will find that the seawater in some areas will rise greatly.

what is the time law of high tide and low tide in the sea?

the time law of high tide and low tide in the sea: high tide and low tide are generally twice a day.

In one day, except for the north and south poles and some areas, the tides rise and fall twice, with a period of 12 hours and 25 minutes, twice a day, and ***24 hours and 5 minutes, so the time of tide rise and fall is delayed by 5 minutes every day.

Irregularities

Usually, the tidal range between two tides in a day is not equal, and it is not equal at the time of high tide and low tide. This irregular phenomenon is called the diurnal inequality of tides. The higher one in the climax is called high climax, and the lower one is called low climax; The low tide is called low tide, and the high tide is called high tide.

calculation method

The specific calculation method is: according to the lunar calendar, if the number of days is less than 15, the number is directly multiplied by .8, and the obtained figure is the highest climax time of the day; If the number of days is greater than 15. The number of days must be subtracted from 15 and then multiplied by .8, and the number obtained is the highest climax time of the day. At the same time, the interval between high tide and low tide is generally 6 hours, which means that the high tide and low tide are twice a day. The high tide usually lasts for more than an hour before the ebb tide begins, and the lowest tide time is in the middle of two high tides.