Causes of late spring cold

Why is there a late spring chill and the reasons for its formation?

Late spring cold means that the temperature in spring is lower than in previous years, so why is there late spring cold? How long will the late spring chill last? Knowing these conditions can make us do a better job of cold protection and warmth. Let's talk about why there is a late spring chill and how long it will last.

Why is there a late spring chill?

Late spring cold refers to the weather phenomenon that the temperature rises rapidly in early spring (generally refers to March) and the temperature is lower than normal in late spring (generally refers to April or May). Long-term rainy weather or frequent cold air intrusion, or under the control of continuous cold and high pressure, strong radiation cooling in sunny nights is easy to cause late spring cold. The climate is changeable in early spring. If the cold air is strong, the temperature can drop to below 10℃, even in rainy and snowy weather. At this time, it is often sunny during the day, which makes people feel that "warm wind makes tourists drunk", but it is chilly in the morning and evening, which makes people feel "chilly in spring". Calendar network said that this kind of "fickle" weather that people can't adapt to is what is usually called "cold spring". It is easy to adversely affect agricultural production and residents' lives.

Causes of late spring cold

Late spring cold is a common weather phenomenon, not only in China, but also in Japan, North Korea, India and the United States. The reason is not complicated. Spring in China (around March) is a transitional period of winter wind direction and summer monsoon, during which cold air from the northwest often intrudes intermittently, and the cold air goes south and sticks to the warm and humid airflow in the south, resulting in continuous low temperature and rainy weather. Generally speaking, when the ten-day average temperature is more than 2℃ lower than normal, there will be more serious late spring cold. The later the cold air goes south, the stronger it becomes, the wider the cooling range, and the greater the possibility of cold in spring.

In the four seasons of the year, the season with the greatest changes in meteorological elements such as temperature, airflow and air pressure is spring. It is often sunny during the day, which makes people feel "warm wind makes tourists drunk", but it is chilly in the morning and evening, which makes people feel "chilly in spring". This unpredictable "fickle" weather is commonly known as "cold spring". According to historical data, the probability of "late spring cold" in Beijing within 30 years is about 57%. Especially in early spring, this climate feature is particularly obvious. For example, on March 8, the highest temperature in the southern suburbs observatory has reached 15.2℃, while the lowest temperature is only 3.3℃, and the temperature difference between morning and evening is still relatively large.

Standard of cold in late spring

Standard of late spring cold: Agrometeorological experiments show that the average daily temperature is ≤ 65438 02℃ and the maintenance period is ≥3 days, which is not conducive to seedling growth. If the cooling is accompanied by rainy weather, the harm will be even greater, which is a relatively recognized indicator. In southern China, the spring sowing time comes first and then comes, and the period and intensity index of the cold spring are also slightly different. In southern China, the spring sowing time comes first and then comes, and the period and intensity index of the cold spring are also slightly different.

The monthly standards in Yunnan Province are:

(1) February standard: the average daily average temperature for four consecutive days has a negative anomaly, and the absolute value is greater than or equal to 5℃; Or the absolute value of the negative anomaly of the minimum temperature on a certain day is greater than or equal to 5.9℃ (the negative anomaly is the monthly average temperature or the monthly average minimum temperature).

(2) March standard: the moving average of the daily average temperature for four consecutive days has a negative anomaly, and the absolute value is greater than or equal to 6℃; Or on a certain day, the lowest temperature appears negative anomaly, and the absolute value is greater than or equal to 5.7℃.

(3) April standard: the average daily average temperature for four consecutive days has a negative anomaly, and the absolute value is greater than or equal to 7.5℃; Or on a certain day, the lowest temperature appears negative anomaly, and the absolute value is greater than or equal to 7.2℃.

Prevent the harm of late spring cold to health

China is a typical country with monsoon climate. Winter is controlled by the winter wind from the north, and the climate is cold and dry. The temperature changes suddenly in spring, and the air is cold and dry. As the weather gets warmer, people's cold resistance and disease resistance will decline, and they can't bear the stimulation of sudden cold air, which directly affects the defense function of respiratory mucosa, and the whole body's disease resistance will decline, which will easily lead to the disorder of human autonomic nervous system and the weakening of regulatory function. Therefore, spring is the season of many diseases, such as influenza, meningitis and viral hepatitis. At the same time, patients with respiratory diseases and cardiovascular and cerebrovascular diseases have also increased significantly, especially the elderly and children with low resistance. If we don't pay attention to prevention, "spring cold" will do some harm to human health.

Health experts said that in order to prevent the attack of "late spring cold", we should pay attention to listening to the weather forecast, pay attention to cold and warmth according to the weather changes, and increase or decrease clothes in a timely and moderate manner, which can follow the law of "spring cover". "Spring cover" depends on the meteorological index and the weather. The temperature is low in the morning and evening in spring, so it can be properly "covered". At sunny noon, when the temperature reaches 10℃ or above, clothes can be reduced appropriately; When spring is in full bloom and the sun is shining, we should take part in more sports activities to enhance the body's immunity and disease resistance, which can ensure the blood circulation of important organs such as the brain and heart, make people energetic and reduce the occurrence of cardiovascular and cerebrovascular diseases. Also pay attention to scientific diet and daily life, often open windows and ventilate indoors, and try to avoid staying in crowded places; Spend the spring with changeable climate safely.

Matters needing attention in late spring cold

1, the most important thing in cold and warm is to keep warm.

As the saying goes, "A child's face changes three times a day in spring." This is the climate in spring. Calendar network reminds that spring is a season with changeable climate. Although spring is getting warmer gradually, it is still cold in the morning and evening, and the number of cold air activities is also frequent, and it will be cold from time to time in spring. If you take off your cotton-padded clothes too early, once the cold air strikes, you may not be able to adapt at once, and your body's resistance will drop, making you easy to catch a cold or even have a fever. Especially for the elderly with weak constitution and children with weak resistance, we should wear more clothes to avoid catching a cold and causing diseases. Professor Zhu Lingyun, an expert in internal medicine of the Municipal Hospital of Traditional Chinese Medicine, reminded that patients with asthma and coronary heart disease should wear more clothes in spring to avoid the recurrence of old diseases.

In addition, many people don't like to sleep with thick quilts in spring, or even sleep with the windows open. As we all know, people's physical resistance is the worst in sleep, and some common diseases in spring are also acquired at this time. If you sleep with the window open at night, the cold wind will easily induce arthritis, low back pain and other diseases, and the root cause will be difficult to treat in the future. Therefore, according to the theory of traditional Chinese medicine, "Spring covers autumn and freezes", and spring is even more important.

2. There are many stresses in spring exercises.

First of all, it is not advisable to exercise prematurely in spring. It is foggy and the temperature is low in spring morning. In spring, all kinds of bacteria are in an active breeding period, which is easy to spread into the air. In addition, if there is much dust, foggy days are not suitable for exercise. China Wang Chi said that if you start exercising before the sun comes out, plants may have no time for photosynthesis and the oxygen content is extremely low.

In addition, spring exercise should not be too intense, because people's muscles and ligaments are still relatively stiff, and it is easy to sprain if they are not fully prepared before exercise. Warm-up activities can choose walking, running and other full-body exercises to help open the whole body muscles. It is also necessary to eat in moderation. Exercise on an empty stomach may make people dizzy. It is recommended to drink some porridge properly, supplement some water and increase body heat. During exercise, we should also pay attention to the time and intensity of exercise. Slow-paced sports with a small amount of exercise are more suitable, such as jogging, walking, Tai Chi, mountain climbing and flying kites. Pay attention to adjust your own rhythm and exercise scientifically.

3, nourishing the liver in spring avoids acid, greasy and alcohol.

Spring is a season of vigorous liver fire, and the focus of spring health care is to nourish the liver. When the liver fire is strong, it is easy to be weak in the spleen and stomach. Chinese medicine believes that "beginning of spring has been sour and sweet for 72 days to nourish his temper." In other words, eat less acid in spring to increase sweetness. Eating too much acidic food will make the liver fire more prosperous, while sweet food can effectively regulate the liver fire. If you eat more yam, chrysanthemum, Malantou, leek, chicken liver and so on. It can play its due role in clearing the liver. However, it is not advisable to eat too much greasy food such as meat in spring. Alcohol is the number one enemy of the liver. Excessive drinking can also lead to fat accumulation in the liver, causing fatty liver.

China Wang Chi suggested that nourishing the liver in spring should avoid acid, greasy and alcohol. It is also worth reminding that fresh fruits in spring must wait until they are ripe and sweet. Unfamiliar fruit is too sour, and eating too much is easy to hurt the liver. In addition, fatty foods such as mutton, marine fish and shrimp should be avoided in spring, and attention should be paid to the intake of vitamins, inorganic salts and high-quality protein. Medical research also shows that the lack of adequate vitamin B can easily lead to sleepiness in spring, and vitamins can also enhance human immunity.