When is it hot in summer?

English name: Lesser Heat

Definition: the eleventh day of the 24 solar terms falls on July 7 or 8; It means the weather is getting hot.

The origin of summer solar terms

On July 7th or 8th every year, when the sun reaches longitude 105, it is considered as a slight summer heat. "Twenty-four solar terms": "June Festival" ... It is also hot in summer, and it is small at the beginning of the month, big in the month, and still small today. "Summer heat. The ancients thought that the summer heat period was not the hottest time of the year, so it was called summer heat. There is also a solar term ballad: "Little summer is not hot, big summer is three days." It is pointed out that the hottest period of the year has arrived, but it has not reached the extreme hot level. As the saying goes, "the heat is at three volts." The dog days in China generally appear in the summer to the next 28 days, which is the so-called "summer solstice is the first of the night"

In ancient China, the summer heat was divided into three periods: "First, it was warm and windy; Second, wait for crickets to live in space; The third waiting eagle began to crow. " In summer, there is no cool wind on the earth, and all the winds carry heat waves; The Book of Songs? In July, the words to describe crickets are "July is in the wild, August is in the house, September is in the house, and October crickets enter my bed." August mentioned in this paper is June in the summer calendar, which is a short time in summer. Because of the heat, crickets leave the field and go to the corner of the yard to escape the heat. In this solar term, the eagle is in the cool high air movement, because the ground temperature is too high.

However, according to the surface climate data in China (197 1 ~ 2000), the extreme maximum temperature in July appears in midsummer in most areas except Qinghai, Gansu, Shanxi, Inner Mongolia and Anhui, and in most provinces. The average temperature in July is higher than that in August in most parts of 32 provinces and cities (Taiwan Province Province). July is the hottest month of the year, and the light summer in July is actually very hot.

Trees are shady and summer is hot. The average temperature in the south is about 26℃ in the light summer, which is already midsummer and quite hot, but it is not the hottest time yet. In mid-July all the year round, in the low-altitude valley area of southeastern South China, the concentration period of daily average temperature higher than 30℃ and daily maximum temperature higher than 35℃ can begin to appear, which is not conducive to heading and flowering of hybrid rice. In addition to fully considering this factor in the layout in advance, corresponding remedial measures should be taken for those that have been planted. In the northern part of the northwest plateau, frost and snow can still be seen at this time, which is equivalent to the scene of early spring in South China.

Around the summer, the western part of South China enters the season with the most rainstorm, and the number of rainstorm days in July and August can account for more than 75% of the whole year, usually about 3 days. Mountain torrents often occur in places with large relief, and even cause mudslides. However, in the eastern part of South China, due to the frequent control of subtropical high, the weather is sunny and hot, and after experiencing a slight summer heat, it began to enter the summer drought period. The climatic characteristics of drought in the east and waterlogging in the west in most parts of southern China have a great relationship with agricultural abundance and waterlogging, so we must take measures to ensure the harvest of drought and waterlogging as soon as possible to minimize the harm.

Around the summer heat, most of southern China entered the season with the most thunderstorms. Thunderstorm is a disastrous weather phenomenon, often accompanied by strong winds, heavy rain and sometimes hail, which is easy to cause disasters and must be prevented.

low-grade fever

On July 7th or 8th every year, when the sun reaches longitude 105, it is considered as a slight summer heat. "Twenty-four solar terms": "June Festival" ... It is also hot in summer, and it is small at the beginning of the month, big in the month, and still small today. "Summer heat" means hot, it is a little hot, not very hot. It means that the weather is getting hotter, but it is not the hottest, and most parts of the country are basically in line with it. At this time, the Meiyu in the Jianghuai Basin is coming to an end, and the temperature in long summer has risen and entered the summer drought period; However, when North China and Northeast China entered the rainy season, tropical cyclones were active frequently, and the number of tropical cyclones landing in China began to increase. After the summer, the south should pay attention to drought resistance and the north should pay attention to flood control. Crops all over the country have entered a vigorous growth period, and it is necessary to strengthen field management. Signs of slight heat in summer; Plum blossom Fall into an ambush.

In ancient China, the summer heat was divided into three periods: "First, it was warm and windy; Second, wait for crickets to live in space; The third waiting eagle began to crow. " In summer, there is no cool wind on the earth, and all the winds carry heat waves; The Book of Songs? In July, the words to describe crickets are "July is in the wild, August is in the house, September is in the house, and October crickets enter my bed." August mentioned in this paper is June in the summer calendar, which is a short time in summer. Because of the heat, crickets leave the field and go to the corner of the yard to escape the heat. In this solar term, the eagle is in the cool high air movement, because the ground temperature is too high.

Before and after the summer heat, agricultural production was mainly busy with field management except winter and spring wheat harvesting in Northeast China and Northwest China. Early rice is in the late filling stage, and early-maturing varieties should be harvested before the heat, and the field should be kept dry, moist and dry. Mid-season rice has entered booting stage at jointing stage, so it should be topdressing panicle fertilizer according to its growth situation to promote large panicle and more grains. The single-season late rice is tillering, so tillering fertilizer should be applied as soon as possible. The second night seedlings should be well protected against pests and diseases, and "marriage fertilizer" should be applied 5-7 days before planting. "It's hot in summer, and the cotton keeps pruning." In most cotton areas, cotton began to blossom and boll, and its growth was the most vigorous. At the same time, it is necessary to prune and rake the old leaves in time, coordinate the distribution of nutrients in the plants, enhance ventilation and light transmission, improve the microclimate of the population, and reduce the shedding of buds and bolls. High temperature in midsummer is the season when aphids, red spiders and other pests flourish, and timely prevention and control of pests and diseases is another important link in field management. "

Since the beginning of summer, the plum rains in the Jianghuai basin have ended one after another, and the southeast monsoon rainy season from the Pacific Ocean has begun to appear in the vast areas north of Huaihe River and Qinling Mountain in eastern China, with an obvious increase in precipitation and relatively concentrated rainfall. South China, Southwest China and Qinghai-Tibet Plateau are also in the southwest monsoon rainy season from the Indian Ocean and the South China Sea. However, under the control of subtropical high, the middle and lower reaches of the Yangtze River are generally hot and rainy, with frequent droughts in summer, which has a great impact on agricultural production. It is very important to store water as soon as possible to prevent drought. An agricultural proverb says, "Rain on a rainy day is rice in a pot". Although the precipitation brought by thunderstorms, tropical storms or typhoons at this time is very beneficial to the growth of crops such as rice, it sometimes has adverse effects on dry crops and vegetables such as cotton and soybeans.

In some years, the cold air force in the north is still strong before and after the slight summer heat, and it is evenly matched with the warm air in the south in the middle and lower reaches of the Yangtze River, leading to frontal thunderstorms. Xiao Xia Yi Lei, hang Huangmei upside down. Thundershowers in summer are often the weather information of "Huangmei hanging upside down", which indicates that the rain belt will stay in the middle and lower reaches of the Yangtze River for some time.

Trees are shady and summer is hot. The average temperature in the south is about 26℃ in the light summer, which is already midsummer and quite hot, but it is not the hottest time yet. In mid-July all the year round, in the low-altitude valley area of southeastern South China, the concentration period of daily average temperature higher than 30℃ and daily maximum temperature higher than 35℃ can begin to appear, which is not conducive to heading and flowering of hybrid rice. In addition to fully considering this factor in the layout in advance, corresponding remedial measures should be taken for those that have been planted. In the northern part of the northwest plateau, frost and snow can still be seen at this time, which is equivalent to the scene of early spring in South China.

Around the summer, the western part of South China enters the season with the most rainstorm, and the number of rainstorm days in July and August can account for more than 75% of the whole year, usually about 3 days. Mountain torrents often occur in places with large relief, and even cause mudslides. However, in the eastern part of South China, due to the frequent control of subtropical high, the weather is sunny and hot, and after experiencing a slight summer heat, it began to enter the summer drought period. The climatic characteristics of drought in the east and waterlogging in the west in most parts of southern China have a great relationship with agricultural abundance and waterlogging, so we must take measures to ensure the harvest of drought and waterlogging as soon as possible to minimize the harm.

Around the summer heat, most of southern China entered the season with the most thunderstorms. Thunderstorm is a disastrous weather phenomenon, often accompanied by strong winds, heavy rain and sometimes hail, which is easy to cause disasters and must be prevented.