What does the vernal equinox mean? Geography.

The vernal equinox is one of the 24 solar terms. On the vernal equinox, the sun shines almost directly on the equator of the earth, and the whole world is almost as long as day and night. After the vernal equinox, the direct point of the sun began to enter the northern hemisphere, and the days became longer and the nights became shorter in all parts of the northern hemisphere.

During the vernal equinox, the daily average temperature in all parts of China rose steadily to above 0℃ except the alpine mountain area and the area north of 45 north latitude. At this time, the cold has passed and the temperature has risen rapidly, especially in North China and Huanghuai Plain. The daily average temperature rises to above 10℃ almost at the same time as the rainy areas along the Yangtze River and the south of the Yangtze River, entering a bright spring.

Extended data:

Every year on March 20th of the Gregorian calendar, when the sun is located at 0 (vernal equinox), it is the vernal equinox. On this day, the sun shines almost directly on the equator of the earth, and the whole world is almost as long as day and night (regardless of the refraction of sunlight by the atmosphere and the shadow in the morning). After the vernal equinox, the direct point of the sun continues to move from the equator to the northern hemisphere, where the days are long and the nights are short, that is, the days are longer than the nights in a day; In the southern hemisphere, the days are shorter and the nights are longer, that is, the days are shorter than the nights in a day. Therefore, the vernal equinox is also called the ascending equinox.