What's the difference between summer solstice and summer heat? Is it hot from summer solstice to summer?

Introduction: Summer solstice and summer heat belong to summer solar terms. The summer solstice appears faster than the great summer heat, and there is a slight summer heat between them, so these two solar terms are different and have great differences. First of all, the time is different and the heat is different. If you want to know the difference between summer solstice and great heat, let's take a look at my introduction.

What's the difference between summer solstice and summer heat?

Summer solstice

Summer solstice is one of the 24 solar terms, which occurs 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. During the summer solstice in Beijing, the daytime can be as long as 15 hours, and the height of the sun is as high as 73 32' at noon. 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. After this day, I went back. The point of direct sunlight moved southward from the Tropic of Cancer, and the days in the northern hemisphere became shorter day by day. After the summer solstice, the height angle of the sun at noon will also decrease day by day in the Tropic of Cancer and its northern area. At the same time, after the arrival of the summer solstice, the stars in the night sky gradually became summer stars.

Major Heat

Summer is one of the twenty-four solar terms of the lunar calendar, and the sun is located in the yellow meridian 120. In the hot summer, Han people have the custom of drinking tea, drying ginger and burning incense. "Twenty-four solar terms" said: "Summer is in the middle of June. Summer, summer, size, small at the beginning of the month, big in the month, and still hot today. " Its climatic characteristics are: "Dou refers to C as a great summer heat, and the weather in Sri Lanka is stronger than a small summer heat, so it is called a great summer heat." The summer solar term is just around the Mid-Autumn Festival in the dog days, which is the hottest period of the year, with the highest temperature and the fastest growth of crops. At the same time, various meteorological disasters such as drought, waterlogging and wind disasters are also the most frequent in many areas.

The summer heat is the twelfth solar term in the twenty-four solar terms of the lunar calendar. At this time, the sun reaches the longitude of the yellow meridian 120 degrees. "Tongwei Filial Piety Helps the Gods": "The fifteenth day of Xia Hou is not a big summer, and it is in the middle of June. The small ones and the big ones are extremely hot, and they are divided into sizes. It was small at first, and it became big after reading it. " At this time, before and after the mid-autumn period, most parts of China are the hottest period in a year, and the growth rate of heat-loving crops is also the fastest. The working people of the Han nationality divide the summer heat into three periods: "One period is rotten grass like fireflies; Second, wait for the soil to moisten and cool off the heat; It will be fine when it rains. " There are more than 2000 species of fireflies in the world, which are divided into aquatic and terrestrial species. Terrestrial fireflies lay eggs on hay, and when it is hot, fireflies ovulate, so the ancients thought fireflies were made of rotten grass. The second weather is that the weather becomes sultry and the land is wet. The third kind of weather is frequent thunderstorm, which weakens the heat and humidity, and the weather begins to transition to beginning of autumn.

Ancient books record the great summer heat, in mid-June. Solve the slight summer heat. Rotten grass is a firefly. Dan Liang, Danbird, Night Light and Night Candle are all aliases of fireflies. From the extreme of Ming, subtle things will turn into Ming. Shi Mao said: Yao Xiao Yao Xing. The other, shaped like Mi Chong, also has a fire on its tail. If you don't talk about it, it won't be the same anymore. The sound of the earth is dotted with heat. Wet, so it is wet due to steaming. Summer heat, commonly known as filth, is also hot. When it rains heavily. I waited for the humid summer heat before, and the steam was depressed. Now it rains heavily to cool off the heat.

Is summer solstice hot or hot?

The high temperature in summer is hotter than the solstice in summer, which is the hottest period in a year.

There is a proverb in "Hot Summer": "The heat is unbearable, and you can't stop screaming when you know it. Grasping both, heatstroke prevention is the most important. "

The summer solstice is the period when the direct point of the sun reaches the northernmost-Tropic of Cancer at 23.5 N, and the solar altitude angle is the largest in most parts of China. Although it is the period with the largest solar radiation, it is not the period with the highest temperature.

Because solar radiation and atmospheric warming have two links, they are affected by many factors.

Link 1: Solar radiation warms the surface;

Link 2: Ground radiation warms the atmosphere. Both links need time to reach the maximum, so the appearance of the highest temperature in the atmosphere will be delayed.

There are many factors in the process of two links. Among the many factors that affect atmospheric warming, the most important is weather conditions, less rainfall, sunny weather and high atmospheric temperature. For example, under the control of subtropical high at this time, the middle and lower reaches of the Yangtze River are sunny and rainy, so the temperature is high. For example, Nanjing, Wuhan, Chongqing and China are three famous cities with stoves along the Yangtze River.

From the summer solstice, the surface absorbs heat and the temperature keeps rising, and it is not until the summer heat that the temperature rises to the highest.

Why is the high temperature in summer hotter than the summer solstice?

The dog days refer to the first, middle and last three days, from mid-July to mid-August. After the summer solstice, although the days are getting shorter and the nights are getting longer, the days are longer than the nights in a day. Every day, the ground absorbs more heat than it emits, and the temperature near the ground is getting higher every day.

During the "three volts" period, the heat absorbed by the ground is almost less than the heat emitted, and the weather is the hottest. After that, the heat absorbed by the ground began to be less than the heat emitted by the ground, and the temperature gradually decreased. Therefore, the hottest time of the year generally appears in the "three volts" summer solstice.

The summer solar term is the hottest solar term in a year. The ancient book "Twenty-four solar terms" said: "It is extremely hot in the summer." This is enough to explain the fiery degree of this solar term. The reason why it is extremely hot during the "Great Summer" is that since the beginning of summer, the heat absorbed from the ground sun during the day is more than that emitted at night, and the heat keeps accumulating. During summer, accumulated heat reaches its peak, so summer is the hottest.

Sunlight shines on the ground, which makes it hot, and the heat absorbed by the ground is released, which makes the air dry. The temperature of air is mainly obtained indirectly from the ground. Although at noon in summer, the sun shines on the ground closest to direct light, and both the ground and the air are strongly heated, the heat released by the ground is less than the heat provided by the sun, so this is not the hottest time.

After noon, the ground temperature can continue to rise until the heat released by the ground is equal to the heat provided by the sun, and the ground temperature can rise to the highest; The temperature rise near the ground must be obtained from the heat released from the ground, which takes time, so the hottest time in summer is not at noon, but at two or three o'clock in the afternoon.