What are the characteristics of the vernal equinox?

What are the characteristics of the vernal equinox?

1. On the vernal equinox, the northern and southern hemispheres share the day and night equally, that is to say, day and night are the same in almost all parts of the world.

2. During the vernal equinox, the East Asian trough is obviously weakened, and the ridge activity in the westerly belt is obviously enhanced. In windy and dusty weather in the north, when the long wave trough moves eastward, there will be continuous rainy and low temperature weather in late spring.

3. During the spring equinox, the temperature rose rapidly, and the average daily temperature in most parts of China was stable above 0℃.

4. The precipitation in the south is increasing rapidly, but there are few in the northeast, north China and northwest, so crops should resist spring drought.

The vernal equinox is one of the 24 solar terms and the midpoint of spring. Every year in February of the lunar calendar (March 20th or 2 1 day of Gregorian calendar) 15 or so, the sun is at 0.

On the vernal equinox, the sun shines directly at the equator of the earth, and the seasons in the northern and southern hemispheres are opposite. The northern hemisphere is the vernal equinox and the southern hemisphere is the autumnal equinox. The vernal equinox is also the New Year in Iran, Turkey, Afghanistan, Uzbekistan and other countries. In China, there are folk customs of hiking, flying kites, drinking and picking wild vegetables at the vernal equinox.

Hydrometeorological characteristics of vernal equinox

aeolian sand

During the vernal equinox, the northwest, the northern part of North China and most of the northeast are still in the transitional stage from winter to spring, with sunny and windy days, and it is warm and cold at first sight. According to the statistics of dusty weather in recent years, April is the most frequent, followed by March, and the vernal equinox is 15 days, that is, from the end of March to the beginning of April. In these areas, dust blown by strong winds and floating dust from high altitude, especially the air pollution caused by dust storms, have always been the focus of attention and become a hot topic for some time.

Low temperature and humid weather

At the vernal equinox, cold air constantly invades the south of China, and there will be cold weather in spring with low temperature. At this time, the continuous rain will have a great impact on crops.

If the average temperature is lower than 10- 12℃ for more than 5-7 days, it may cause serious rice seedling rot. Because rice and cotton are both thermophilic crops, when the temperature is above 10- 12 and the minimum temperature in sunny days is above 5℃, it is beneficial to all seedlings. Conversely, if there is low temperature and rainy weather, you can imagine.

First frost is the product of cold wave and strong cold air in spring. In the case of warmer climate, cold waves are relatively rare, but we should not be careless.

Abnormal cold weather in early spring

In early spring, the temperature rises quickly, and then it stays low for a while. This weather phenomenon is called late spring cold. In the south, the main influence of late spring cold is the rotten seedlings of early rice. In the north, it will affect the growth of peanuts, vegetables and cotton, and seriously cause the phenomenon of wheat seedling death. There was a very serious cold wave in the middle and lower reaches of the Yangtze River in late spring, which happened to be the vernal equinox, that is, from late March to early April of 1976. Hunan, Jiangxi and Hubei provinces alone lost 700-800 million Jin of grain seeds.

spring drought

In the north, especially in the northwest and north China, there is a saying that "spring drought lasts for ten years and nine months" and "spring rain is as expensive as oil". When there is little rain and snow in winter, winter wheat is in the wintering period and is not very sensitive to water shortage. After March, the soil thawed and the wheat turned green; In spring, crops are sown from south to north. If the precipitation continues to be less at this time, the drought will be clearly reflected, and the situation of seedlings can be imagined.

Pre-flood season in southern China

There are two rainfall concentration periods in South China, one is the first flood season from April to June, and the other is the second flood season formed by typhoon rainfall from July to September. The first flood season begins in early April and reaches its peak in mid-May, with an average of 20 rainstorms per year, with the most in June, accounting for more than half of the total rainstorms. It lasts for a long time and the rain is fierce. Because the "vernal equinox" only touches the beginning of the flood season, I won't go into details here.

What is forbidden to eat at the vernal equinox

Avoid salty things, such as salted fish, bacon, mustard tuber, salted eggs, etc. This kind of food will keep water and sodium in the body, which will easily aggravate the symptoms of patients with hypertension.

The general principle is to avoid heat and cold and strive for neutrality. If you eat cold food, it is accompanied by damp-heat products; If you take Yiyang's products, it should be combined with nourishing yin to achieve a balance between yin and yang.

Avoid spicy food, spicy dry products, such as Chili, curry, Chili, mutton, dog meat, green onions, liquor and so on. This kind of food is easy to dry, which increases the viscosity of sputum and can hurt lung yin.

Avoid all kinds of cool fruits, ice cream, frozen drinks, etc. This cold food hinders the spleen and stomach. It is not conducive to the transportation of water and dampness, and it can accumulate dampness and produce phlegm.

During the vernal equinox, yin and yang in nature are equally divided, and the principle of punctuality should be followed in diet, and the daily diet should be able to keep the body balanced and coordinated. You can't eat anything cold and hot during the vernal equinox. You can eat more cauliflower, lotus seeds and tripe.

Cauliflower can strengthen the body and resist the flu; Lotus seeds can strengthen the essence, strengthen the body, tonify deficiency, eliminate dampness and dispel cold; Tripe can nourish the spleen and stomach, tonify the middle energizer and replenish qi.