Which season has the longest day?
Which season has the longest day: summer solstice
The summer solstice is one of the 24 solar terms, which falls on June 2 1 or 22 of the Gregorian calendar every year. On the day of summer solstice, the sun moves to 90 degrees of the yellow meridian (summer solstice, currently in Gemini), and the position where the sun directly hits the ground reaches the northernmost point of the year, almost directly to the Tropic of Cancer. At this time, the daylight hours in all parts of the northern hemisphere reach the longest in the whole year. For the Tropic of Cancer and its northern area, the summer solstice is also the highest day of the year at noon. In Beijing, the daytime from summer solstice can be as long as 15 hours, and the sun is as high as 73? at noon. 32? . On this day, the northern hemisphere received the most solar radiation, almost twice as much as the southern hemisphere.
Astronomical experts say that the solstice in summer is the turning point of the sun, and it will disappear after this day? Go back? The point of direct sunlight began to move south from the tropic of cancer, and the days in the northern hemisphere began to shorten gradually. After the summer solstice, the Tropic of Cancer and its northern region, the midday sun height angle also began to decrease. At the same time, after the arrival of the summer solstice, the stars in the night sky gradually became summer stars.
The origin of summer solstice
The summer solstice is the earliest of the 24 solar terms. In the 7th century BC, the shadow of the sun was measured by civil soil gauge, thus the summer solstice was determined. According to the "constitutional copy": the summer solstice is called the summer solstice because it has long days and short shadows. Do your best. ? On the summer solstice, the position where the sun directly hits the ground reaches the northernmost point of the year, almost directly on the tropic of cancer (latitude 23? 26'), the days in the northern hemisphere are the longest in a year, and the farther north it is, the longer it is. For example, the daily length of Haikou in Hainan is a little more than 13 hours, Hangzhou is 14 hours, Beijing is about 15 hours, and Mohe in Heilongjiang can reach 17 hours. At the same time, for the Tropic of Cancer and its north, the summer solstice is also the day with the highest sun height at noon in a year. In Beijing, the height of the sun is as high as 73? 32? . On this day, the northern hemisphere received the most solar radiation, almost twice as much as the southern hemisphere. At this time, the southern hemisphere is in the middle of winter.
Astronomical experts say that the solstice in summer is the turning point of the sun, and it will disappear after this day? Go back? . After the summer solstice, the direct point of the sun gradually moved southward, and the days in the northern hemisphere began to shorten gradually. For the Tropic of Cancer and its northern area, after the summer solstice, the height of the noon sun began to decrease day by day. Someone else? After eating noodles on the solstice in summer, one day is shorter than a thread? Wei, a poet in the Tang Dynasty, wrote in "Summer in the North Pool" that "the sundial is cloudy, and the night leakage is long from now on".
In ancient China, the summer solstice was divided into three stages: waiting for the antlers to dissolve; Second, wait for cicadas to start singing; Third, wait for Pinellia ternata. ? Although Mi and Lu belong to the same family, the ancients thought they belonged to Yin and Yang. The deer's horn faces forward, so it belongs to Yang. At the summer solstice, Yin Qi was born, and Yang Qi began to decline, so the front antlers began to fall off. Because rice is cloudy, it falls off at the corner of the winter solstice; After the summer solstice, the male cicada fluttered and sang because of Yin Qi's feeling. Pinellia ternata is a shade-loving herb, named after it was born in swamps or paddy fields in midsummer. It can be seen that in the hot summer, some yin-loving creatures began to appear, while positive creatures began to decline.
China folks divide 15 days from summer to the future into 3 days? What time? Generally, the first time is 3 days, the middle is 5 days, and the last is 7 days. During this period, the temperature in most parts of China was high, the sunshine was sufficient, the crops grew rapidly, and the physiological and ecological water demand was high. Precipitation at this time has a great influence on agricultural output, doesn't it? Are the raindrops worth 1000 yuan in the summer of solstice? Said. In general, the precipitation in the middle and lower reaches of the Yangtze River and Huanghuai area can generally meet the requirements of crop growth. "Jingchu Sui History Collection" records:? It will rain at three o'clock in June, and the family thinks it is sweet, and the whole city congratulates each other. ? It can be seen that as early as 1000 years ago, people had a clear understanding of the characteristics of this rainfall.
Before and after the summer solstice, early rice heading and flowering in the south of Huaihe River, field water management should be fully water heading, wet irrigation, dry and wet, which not only meets the water demand of rice fruiting, but also can ventilate and raise roots, ensure maturity and improve grain weight. As the saying goes, "Summer broadcasting does not allow noon", we should pay close attention to summer broadcasting, strengthen the management of broadcast content, and strive for full seedlings. After the seedlings emerge, they should be spaced, fixed and transplanted in time to make up for the deficiency. During the summer solstice, all kinds of weeds in farmland grow as fast as crops. They not only compete with crops for water, fertilizer and sunlight, but also parasitize various germs and pests. Therefore, the agricultural proverb says, "If you don't hoe the grass at the summer solstice, it's like raising a poisonous snake to bite you." Grasping intertillage and hoeing is one of the most important measures to increase production in summer solstice. Generally, cotton has germinated, and its vegetative growth and reproductive growth are vigorous. Attention should be paid to ridging, intertillage and ridging in time, and ditch cleaning and drainage should be done in the field in rainstorm areas to prevent the harm of waterlogging and rainstorm.
? But isn't the summer solstice hot? ,? How many heads are there on the summer solstice? . Although the summer solstice indicates that the hot summer has arrived, it is not the hottest time. The temperature will continue to rise for some time after the summer solstice, and it will be the hottest weather in about twenty or thirty days.
After the summer solstice, due to the vigorous growth of crops, the rapid growth and spread of weeds, pests and diseases, and the golden season of grass, fertilizer and livestock flourishing in plateau pastoral areas, agricultural production in most parts of southern China entered the field management period. At this time, the rainfall in the western part of South China increased obviously, which gradually changed the distribution trend of rainfall in South China from the east to the east since the spring.
If there is a summer drought, it is generally expected to be lifted at this time. In the past 30 years, the number of large-scale floods in western South China in late June was small, but the degree was serious. Therefore, special attention should be paid to preparing for flood control. The summer solstice solar term is the solar term with the largest annual rainfall in eastern South China, which is often controlled by subtropical high in the future, resulting in summer drought. In order to enhance drought resistance and win a bumper harvest in agriculture, it is an important measure to capture and store pre-dormant rainwater in these areas.
Climatic characteristics
Convective weather
After the summer solstice, the ground is heated strongly and the air convection is strong, and thunderstorms are often easy to form in the afternoon to evening. This kind of hot thunderstorm comes and goes, and the rainfall range is small. People call it? Summer rain across the ridge? . Liu Yuxi, a poet in the Tang Dynasty, skillfully used this weather to write? Sunrise in the east and rain in the west, is it sunny but sunny? A famous poem. The heavy precipitation brought by convective weather is not always as beautiful as described in the poem, and it often brings local disasters. Poet Xu Xinshu? In the summer rain? The description of thunderstorm weather in summer in the poem is also appropriate: In summer, sitting on the platform in summer, frogs sing cicadas and attack the dust. The golden gong sounded like a thunderbolt, and the cold rain hit the face like money. ?
Rainstorm weather
In most cases, summer solstice? During this period, the middle and lower reaches of the Yangtze River and the Jianghuai basin are rainy and frequently rainstorm, which is easy to cause floods and even threaten people's lives and property. Attention should be paid to strengthening flood control.
Jianghuai Meiyu
Is summer solstice in Jianghuai area? Meiyu? In season, it is the yellow ripening period of plums in Jiangnan, and the air is very humid. Cold and warm air masses meet here, forming a trough of low pressure, leading to rainy weather. In this weather, the utensils are moldy and the human body feels uncomfortable. Some mosquitoes breed quickly, and some intestinal bacteria are easy to breed. At this time, we should pay attention to drinking water hygiene and try not to eat cold food to prevent the occurrence and spread of infectious diseases.
High temperature sauna
Like the winter solstice, the summer solstice is also a solar term reflecting the changes of the four seasons. Astronomy stipulates that the summer solstice is the beginning of summer in the northern hemisphere. After the summer solstice, although the direct point of the sun gradually moved southward, the days in the northern hemisphere became shorter and the nights became longer. However, because the heat radiated from the sun to the ground is still more than the heat radiated from the ground to the air, the temperature will continue to rise in the future, so there are? Summer solstice, but not hot? Statement. According to the data of 195 1 -2006, the historical extremes of many cities in the north appeared after the summer solstice.
Customized activities
Sacrifice to gods and ancestors: the solstice in summer is the harvest season. Since ancient times, celebrating harvest and sacrificing ancestors at this time is to pray for a good year. Therefore, the summer solstice, as a festival, was included in the ancient ritual of offering sacrifices to the gods. "Zhou Li? "Spring Official" contains: With the arrival of summer, it brought local things. ? In the Zhou dynasty, sacrifices were made to gods from summer solstice, which meant to eliminate famine, hunger and death. The solstice of summer is just after the wheat harvest. Farmers not only thank God for the bumper harvest, but also pray for it? Autumn newspaper? . Around the summer solstice, some places will hold grand ceremonies? Summer wheat? Is it ancient? Summer festival? The remains of activity.
Summer and shelter: On the solstice of summer, women give each other folding fans, powder and other things. "Fuyang miscellaneous? Politeness:? About the solstice of summer, there are resignations about entering fans and powder capsules. Fan? , thus giving birth to the wind; ? Powder fat? Apply it to dispel body heat and turbid qi and prevent miliaria. In court? Summer Solstice? And then the royal family took it out Suitable for storage in winter and use in summer? Ice? Summer and shelter? Moreover, since the Zhou Dynasty, it has been used in all dynasties and has become a system.
? Summer Solstice? Food:
? Wheat jiaozi? With what? Summer solstice cake? Jiangnan food customs generally include wheat dumplings, millet, plums, wonton, noodle soup and so on. Wujiang county annals:? On the solstice of summer, we make wheat jiaozi, finish the sacrifice first, and then pay each other. ? Not only eat? Wheat jiaozi? And will? Wheat jiaozi? As gifts, give gifts to each other. On the solstice of summer, farmers will also roll pancakes, bake them, and add vegetables, pods, tofu and bacon to eat after ancestor worship. Summer solstice cake? , or distributed to friends and family.
Solstice wonton in winter and noodles in summer: China people have had this kind of food since ancient times? Winter solstice wonton and summer solstice noodles? It is said that eating noodles from summer solstice in the south of the Yangtze River is an important custom in many areas. After eating noodles on the solstice in summer, one day is shorter than a thread? Statement. There are many kinds of noodles in the south, such as Yangchun noodles, dried soup noodles, shredded pork noodles, three fresh noodles, sesame oil noodles and cold noodles, while noodles with gravy and noodles with dregs in the north. ? Because new wheat has appeared from summer to sun, eating noodles from summer to sun also means tasting new things. ?
Summer solstice heatstroke prevention
From summer to later, there are initial, intermediate and final stages of accommodation. Dog days are the hottest period of the year, and it is easy to get sick from heatstroke. Therefore, in the old days, in order to be safe, more ghosts were exorcised, and at the same time, attention was paid to taking a rest at noon and taking supplements. In addition, special attention should be paid to heatstroke prevention and cooling. Nevertheless, summer consumes the health of many people, because they can't eat well, sleep well and endure the heat, so it is called dry summer. There is a custom in the north, which is to weigh the child regularly to see if his weight has increased or decreased, so as to observe the growth of the child.
Secondly, the use of heatstroke prevention tools, such as umbrellas, fans, cool hats, summer mats, bamboo ladies and so on.
Fans originated very early, as tools for growing grain and kitchen utensils for fanning fires in agricultural production, and were later improved to become cooling appliances for heatstroke prevention and heat drive, and later evolved into opera appliances. There were feather fans in the Zhou Dynasty to enjoy the cool, and long-handled fans were unearthed from Mawangdui Han Tomb. Folk fans vary from place to place, including banana fans, cattail fans, feather fans and silk fans. Paper folding fans appeared only after the Tang Dynasty.
In ancient times, sleeping mats made of various fiber materials were widely used, such as reed mats, bamboo mats and ivory silk mats (the manufacturing method originated in the Han Dynasty and prevailed in the Ming and Qing Dynasties, and the finished products were very luxurious). The porcelain pillow popular in ancient times is also a kind of heatstroke prevention bedding. There are also bamboo pillows, that is, Mrs. Zhu, also known as Baihua Niangzi, Zhu Ji and Qing Nv. Wu Youru has a painting treasure? Bamboo demon dream? There is a picture of a man lying in bed, holding Mrs. Zhu to sleep. Because the days are long and the weather is hot in summer, it is difficult to fall asleep at night, so siesta is advocated everywhere. In addition, people also like swimming in summer, women and children playing in the water, keeping goldfish, harpoon fish, catching turtles, catching frogs, catching fish, catching eels and hunting in summer.