In March in Zhejiang, the temperature plummeted and it began to snow. What is the reason for the big weather change?
How powerful is this cold air? It's snowing everywhere in Zhejiang! At about 9: 00 pm on March 1 day, affected by cold air, the temperature dropped to -2℃ in Qingliangfeng National Nature Reserve, Zhejiang Province, a protection station at an altitude of 1 100 meters, and snow seeds and snowflakes floated in the sky. It was really unusual to snow in March. Many netizens said: No wonder it's so cold!
At present, cold air is affecting Zhejiang, and the average daily temperature in southern Zhejiang and coastal areas has dropped by 6 ~ 8℃, while in other areas it has dropped by 4 ~ 6℃. On the morning of the 3rd, except for the coastal areas, the minimum temperature will drop to 2 ~ 4℃ in most areas, 0 ~ 2℃ in mountainous areas and 9℃ in Yuhuan! The weather has been depressed these days, and many places in Zhejiang are still experiencing windy weather. As of 1 night 2 1: 57, 28 areas have issued yellow gale warning signals. Last week, the temperature was still 20℃, and in March 1, the wind and rain cooled down. This "roller coaster" weather changes, giving people a "roller coaster" feeling.
Speaking of cold spring, many people are familiar with it. It mainly refers to the weather phenomenon that the average temperature drops to a lower level than that in the same period of normal years and lasts for a period of time under the background that the temperature generally rises every spring (March-May) in China, affected by the frequent southward cold air in the north or the continuous rainfall in the south. For the northern region, the cold spring means that the cold air force is enhanced and the temperature drops sharply; For the southern region, it is usually associated with low temperature and rainy weather.
When it comes to the influence of late spring cold, it is not only the alternation of cold and warm caused by people's somatosensory temperature changes, but more importantly, the late spring cold has a great influence on agricultural production. If the agricultural production in the north encounters a cold spring, it is usually April-May and March-May in the south.
Astronomical reasons mainly include the following changes in solar radiation intensity: solar radiation may change in the range of 10 ~ 109. Visible light radiation is generally between 0.05%- 1.0%, and the maximum is not more than 2.5%. The change of solar radiation is mainly manifested in the radiation from ultraviolet rays to X-rays and radio waves. When the solar activity is strong, this part of the radiation is strongly disturbed. If the solar radiation changes by 65438 0%, the temperature will change by 0.65 ~ 2.00℃.
Changes of Earth's orbital elements: The changes of Earth's orbital elements (eccentricity of Earth's orbital ellipse, inclination of axis of rotation and precession) make the solar radiation received at different latitudes change in different seasons, which is usually used to explain the alternation of Quaternary glacial and interglacial periods.
Quasi-periodic variation of solar activity: Research shows that quasi-periodic variation of solar activity is closely related to climate vibration. Such as the activity of sunspots, the law is 1 1 year, 22 years and 88 ~ 90 years. But at present, people want to explore the causes of climate change according to the law of solar change, and have not achieved satisfactory results.