What are the most obvious changes in the four seasons?

The area with the most obvious seasonal change is the mid-latitude area, including subtropical zone, warm temperate zone, middle temperate zone (cold temperate zone) and cold temperate zone (sub-cold zone), especially the middle temperate zone.

1, seasonal change refers to the change of the length of day and night and the height of the sun at noon caused by the rotation and revolution of the earth, which causes changes in climate, ecology, agriculture and so on. The area with the most obvious seasonal change is the mid-latitude area, including subtropical zone, warm temperate zone, middle temperate zone (cold temperate zone) and cold temperate zone (sub-cold zone), especially the middle temperate zone.

2. The climate in the mid-latitude region is characterized by four distinct seasons, with the temperature rising gradually in spring, hot and humid in summer, decreasing gradually in autumn and cold and dry in winter. This climate feature is related to geographical location. The climate in mid-latitude area is influenced by solar radiation, topography, ocean and atmospheric circulation.

3. In mid-latitude areas, the temperature rises gradually in spring. This is because the direct point of the sun moves northward, the sunshine time in the northern hemisphere gradually increases, and the solar radiation absorbed by the surface also increases, resulting in an increase in temperature. In addition, the rainfall in spring is gradually increasing, which is caused by the frontal activity formed by the encounter between warm and humid air and cold air.

Summer is the hottest season in a year, with high temperature, high humidity and much precipitation in mid-latitude areas. This is because the direct point of the sun is located near the equator in summer, and the sunshine time in the northern hemisphere is the longest, and the surface absorbs the most solar radiation, resulting in the highest temperature. At the same time, summer is also the season when typhoons frequently land, and the rainstorm brought by typhoons will also aggravate the local precipitation.

5. The temperature gradually decreases in autumn, which is due to the fact that the direct point of the sun starts to move southward, the sunshine time in the northern hemisphere gradually decreases, and the solar radiation absorbed by the surface also decreases, resulting in the temperature decrease. In addition, autumn is also the arrival of defoliation season. With the change of temperature, the trees gradually shed their leaves, showing a beautiful autumn scenery.

6. Winter is the coldest season in a year, with low temperature, heavy snowfall and strong wind in mid-latitude areas. This is because the direct sunlight point is located near the tropic of Capricorn in winter, and the sunshine time in the northern hemisphere is the shortest, and the surface absorbs the least solar radiation, resulting in the lowest temperature. At the same time, winter is also a season of ice and snow, and heavy snow closes mountains from time to time.

The origin of seasonal variation

1, the seasonal change is the result of the earth's revolution and rotation. The earth's orbit around the sun is an ellipse, so the distance between the earth and the sun will change with time. When the earth is close to the sun, the energy radiated by the sun is greater and the temperature is higher; When the earth is far from the sun, the energy radiated by the sun is small and the temperature is low.

2. In spring, the earth is far away from the sun, the temperature is low, and the plants on the ground begin to grow again; In summer, the earth is closer to the sun, the temperature is higher, plants grow rapidly, and most plants blossom and bear fruit; In autumn, the earth is far away from the sun, the temperature drops gradually, and plants begin to wither; In winter, the earth is closest to the sun, with the lowest temperature, and most plants go into a dormant state.

In addition to the influence of the revolution of the earth, the climatic conditions in different parts of the earth will also affect the changes of the four seasons. For example, due to the influence of tropical climate, the temperature near the equator is relatively stable all year round; However, due to the influence of polar climate, extreme temperature changes will occur in areas near the polar regions.