What are some of the interesting natural phenomena of autumn

Autumn is characterized by a small gap between day and night, a drop in temperature, a good harvest, falling leaves, and dryness.

1. The gap between day and night is small.

Autumn point of direct sunlight.

Moving gradually southward from the Northern Hemisphere, the Sun crosses the equator after the autumnal equinox and shines directly on the Southern Hemisphere.

From the Northern Hemisphere, the angle of the Sun gradually decreases, and the gap between the length of day and night decreases. Day and night are equal in length at the autumnal equinox.

2. The temperature drops.

In our country, it is traditionally based on the 24 solar terms.

The "beginning of autumn" serves as the starting point of autumn. In nature, the yin and yang energy begins to change, the yang energy gradually retreats, the yin energy gradually grows, the climate changes from hot to cold, and everything grows with the cold and gradually declines.

3. Harvest. From the beginning of autumn to autumn, everything in nature begins to grow from luxuriant to fruitful and mature. Autumn is the harvest season, and many plants mature in the fall.

4. Fallen leaves. As the temperature gradually drops, the leaves of many deciduous perennials will gradually change color, wither, and fall, leaving only the branches to survive the winter. And an annual herbaceous plant.

They will come to the end of their lives, withering to death.

5. Drying. Entering autumn means that precipitation, humidity, etc. are at a turning point in the year, tending to decline or decrease, resulting in a dry climate, so in autumn, you should replenish more water to prevent physical discomfort.

1. Fallen leaves. Falling leaves is a natural phenomenon, generally in autumn, most of the deciduous plants and trees begin to fall leaves, the leaves are yellow, curly, falling from the trees, fluttering in the wind, which also represents that after late autumn, winter is coming.

The north of our country is located in the north temperate zone, every autumn, due to the low temperature, the rain is reduced, so that the root absorption of plants is reduced, and the water and inorganic salts obtained by the plant body are greatly reduced, so that the physiological activities such as photosynthesis, respiration and transpiration can not be carried out normally. If the leaves are retained, a large amount of water will be transpired and threaten the survival of the plant. After the cold and drought, new leaves will grow.

2. Autumn rain. A general term for rainy weather during the transition season between summer and autumn or autumn and winter. The autumn rains are more pronounced in the transition season between summer and autumn in eastern China.

In this season, typhoons often make landfall in eastern China and move northward or turn offshore, resulting in the warm and moist air coming with the typhoon and the cold air from the north converging here, resulting in persistent rainy weather.

Sometimes, although there is no typhoon, the warm and moist air will occasionally increase, such as meeting with cold air from the north, it will also cause a period of rainy weather, which is more common in western China.

3. Wild geese fly south.

Every autumn, geese fly from their hometown in Siberia to the south of our country in flocks to spend the winter. The following spring, they return to Siberia after a long journey to lay eggs for breeding.

The wild geese fly very fast, they can fly 68 90 kilometers per hour, and the long journey of several thousand kilometers has to fly for a month or two.

4. Cold dew. On October 8 or 9 every year, it is cold dew when the sun reaches 195° of ecliptic longitude. "Explanation of the Seventy-two Candidate Collections of the Lunar Order" says:

In September, the dew is cold and will condense also. "Cold dew means that the temperature is lower than when the white dew is used, and the dew on the ground is colder and is about to condense into frost.

In the cold and dew season, the vast areas of Nanling and the north have entered autumn, and the northeast and northwest regions have entered or are about to enter winter. First frost is visible in the capital Beijing at this time of year for most years, and snow has generally begun to fall in northeast China and northern Xinjiang, except for the Qinghai-Tibet Plateau, which snows all year round.

5. Frost falls. The first frost that occurs in autumn is called the first frost, and the earlier the first frost, the more harmful it is to the crop. The first frost in various parts of China is gradually delayed from north to south, from high mountains to plains.

Except for the areas with frost throughout the year, the earliest frost is in the northern part of the Daxing'an Mountains, and the frost can generally be seen at the end of August; The first frost in most of Northeast China, Inner Mongolia and Northern Xinjiang is mostly in September; In early October, frost has appeared in Shenyang, Chengde, Yulin, Qamdo to Lhasa; At the beginning of November, frost was visible from Shandong Peninsula, Zhengzhou, Xi'an to northwest Yunnan;

Frost does not begin to appear until early December in areas of eastern China at about 30°N, Hanshui, and Yunnan Province at around 2°N; When the frost in Xiamen, Guangzhou, Baise and Simao was already in early January after the New Year.

The leaves begin to turn yellow, the temperature gradually decreases, etc.

There are many changes in autumn, such as some leaves starting to turn yellow, the temperature gradually dropping, and so on. Autumn is also a harvest season, and there will be a scene of abundant harvest in the orchards and fields.

1. Most of the plants in autumn will have defoliation, and the leaves of the plants will change from green to yellow or red, which is related to the slow and cautious pigments contained in the leaves.

2. The temperature will gradually drop in autumn, generally slower than in winter. Due to the difference in dry and wet conditions, different areas will have cold and rainy weather conditions, or dry and cool meteorological conditions. In the colder late autumn, due to the large temperature difference between day and night, the water vapor transpired during the day will condense at night, either as dew or as frost.

3. In autumn, the direct point of the sun gradually moves southward from the northern hemisphere, and after the autumn equinox, it crosses the equator and the sun shines directly on the southern hemisphere. From the Northern Hemisphere, the angle of the sun gradually decreases, and the gap between day and night becomes smaller. Day and night are equal in length at the autumnal equinox. In autumn, the distance between the Earth and the Sun gradually increases.

4. In autumn, in most areas of southern China, late rice jointing and booting, cotton cracked boll and spit out; Medium rice and summer maize entered the stage of grain filling and maturity. In the eastern and western parts of South China, the task of fighting drought and flood control is still very arduous. In South China after the beginning of autumn, although the season is still in the middle of summer, but"Ten days of the beginning of autumn are all over the ground", golden"Autumn"It's coming.

Which line of stove respect.

Natural Phenomena: Autumn What does the beginning of autumn mean?

About Autumn:

1.colder than summer and warmer than winter;

2.Daylight hours are longer than nighttime hours;

3.People are easy to get tired, commonly known as "autumn sleepiness" and "autumn fatigue", eating more fruits and vegetables, taking a short nap, and active exercise can solve it;

4.Some trees have yellowing and withered leaves;

Fruitful bases, autumn rain, autumn is high and refreshing, and the trees fall leaves in another autumn.

1. Fallen leaves.

In autumn, most of the deciduous plants and trees begin to shed their leaves, and the leaves are yellow, curly, falling from the trees, and fluttering in the wind, which also represents that after late autumn, winter is coming.

Second, the wild geese fly south.

In autumn, when the cold weather in the north is no longer suitable for geese, they fly to the warmer south in flocks. The following spring, they return to the north after a long journey to lay eggs and breed.

3. Fruitful.

In autumn, the fruits on the trees are ripe, and apples, pears, and persimmons are hanging on the branches, creating a harvest scene.

Fourth, the leaves turn red.

The leaves turn red because they contain a lot of anthocyanins. As a site for photosynthesis in leaves, chloroplasts contain not only chlorophyll, which makes leaves green, but also carotenoids, which make leaves yellow.

In summer, the leaves are high in chlorophyll, so the bright green overshadows the yellow. As the temperature drops and the daylight hours become shorter, chlorophyll is broken down in large quantities, revealing other pigments such as carotenoids that are submerged in the leaves.

5. Mid-Autumn Festival.

The Mid-Autumn Festival, also known as the Moon Festival, the Autumn Festival, the Mid-Autumn Festival, the August Festival, the August Festival, the Moon Chasing Festival, the Moon Festival, the Moon Worship Festival, the Daughter's Festival or the Reunion Festival, is a traditional cultural festival popular in many ethnic groups and countries in the Chinese character cultural circle, on the 15th day of the eighth month of the lunar calendarBecause it coincides with the middle of the third autumn, hence the name, and some places set the Mid-Autumn Festival on August 16.

Sandstorms, fog, moon cakes, green-skinned oranges, chrysanthemums, National Day, geese flying south, harvest.

About autumn: 1colder than summer and warmer than winter;

2.Daylight hours are longer than nighttime hours;

3.People are easy to get tired, commonly known as "autumn sleepiness" and "autumn fatigue", eating more fruits and vegetables, taking a short nap, and active exercise can solve it;

4.Some trees.

The leaves of the tree will turn yellow and wither;