Jade case: the ebb and flow of Qiantang River

Year: Song Author:

Tides rise and fall on Qiantang River. Flowers fall six bridges open. Three Zhu San Mao Xiao Zhong dusk. The dream of that year, now the old country, can not bear to look back. Who is he so worried about? The waves on the flat ground carry wind and rain. The sad past is well founded. In the laughter of the Moon Hall, after the words of the pavilion at night, naturally no one understood.

2、

Tide of Qiantang River

Year: Tang Author: Luo Yin

The voice of anger is full of momentum, and the rivers in Russia are floating. There are big letters on the street,

We also know that advection is repetitive. Losing a giant has no bottom, and fighting Xiling has only a head.

Who is in charge when you are stunned, so you can ride a carp and ask Yang Hou.

3、

Equal tide of Qiantang River

Year: Song Author: Hu Zhonggong

The tide rises and falls, and the waves are high and drum.

The river turned sunny to snow, the sea rose and the stone pond was flat.

See you at the end of the sail, and the room is full of waves.

Castle Peak is from wuyue, full of affection.

4、

Crossing Qiantang River to Meet the Tide

Year: Song Author:

The silver pond turned the sky white, and Kunzi became angry from embarrassment.

Clouds roar and thousands of Ma Chi cars rumble.

High-spirited, like an orange, life instantly faded.

One road is blocked, and there are often thousands of boats a day.

I really want to climb the Shu Road, because I have thought about it nine times.

There are all kinds of risks in life, so there must be a lot of storms here.

Don't ask if you want to say anything, and don't be ashamed of drinking.

5、

Watching Qiantang River Tide in Dengzixu Temple

Year: Yuan Author: Fang Xing

The five mountains are divided into two sides, and the stormy waves are thundering through the ages.

Zi Xu is a loyal minister when he dies, and Gou Jian is not a overlord.

I'll start again when the years wear away and the mountains and rivers are magnificent.

The arrow is all there, the eye is broken, and Hongbo Wan Li returns.

The cause of spring tide

Weather explanation: From August 16th to 18th of the lunar calendar, the sun, the moon and the earth are almost in a straight line, so the tidal force (the difference between the gravity of the moon, the sun or other celestial bodies on the earth and the gravity of the earth's center of mass, or the resultant force of the inertial centrifugal force generated by the earth's movement around the center of mass of the earth's moon (sun) and the gravity of the moon (sun)) is the largest. [2]

Geographical location: It is related to the trumpet-shaped estuary of Qiantang River. On the south bank of Qiantang River, nearly 500,000 mu of land was reclaimed to the east of Zheshan Mountain, which blocked the estuary like a peninsula, making the section from Zheshan Mountain to the outside of Qiantang River 12 km look like a bottle with a small belly, and the tide is easy to enter but difficult to retreat. The outer mouth of Hangzhou Bay is 100 km wide, and it is only a few kilometers wide to the outer 12 sections. The riverbed in the east of the estuary suddenly rises and the beach is shallow. When a large number of tides come in from the mouth of Qiantang River, the river surface shrinks rapidly, and then it is related to the sediment deposition under Qiantang River. The sediment deposition blocks and rubs the tidal current, which makes the front slope of the tidal current steep and gentle, thus forming a wave that catches up with the previous wave and then overlaps with the other wave.

Wind direction: the southeast wind is often blown along the coast, and the wind direction is generally consistent with the tidal direction, which is helpful for the tidal direction.

Watching autumn tide in Qiantang has become a custom as early as the Han, Wei and Six Dynasties, especially in the Tang and Song Dynasties. According to legend, August 18 of the lunar calendar is the birthday of the tide god, so the tide peak is the highest. In the Southern Song Dynasty, the imperial court stipulated that the navy division should be inspected on the Qiantang River on this day. Later, they became accustomed to each other, and August 18 gradually became a tide-watching festival. Pan Lang, a poet in the Northern Song Dynasty, wrote in Jiuquanzi:

Long memories of watching the tide, full of people vying to see the river. I suspect that the sea is empty and drums are beating all around. Xiang Tao, the frolic in the frolic, stands upright and keeps the red flag wet. I don't see the dream a few times, but I am still chilling.

This poem is a true portrayal of the activities of "making waves" and "watching the tide" in those years.