400-word weather composition in my life

The blue sky was covered with a silky cloud curtain, and soon, a colorful halo appeared around the sun. It is like a rainbow, but not as bright as a rainbow; The colors of the rainbow are ultraviolet and red, while the halo is just the opposite, ultraviolet and red. This is the "halo", also known as the "cyclotron".

Our ancestors observed and recorded the "halo" very early. As far away as Oracle Bone Inscriptions in Yin Ruins, the word "dizzy" has already appeared. In the Western Zhou Dynasty, "halo" was officially recorded as a celestial phenomenon. Europeans didn't have a detailed record of "halo" until 1630, more than 2000 years later than China.

Although people have noticed this beautiful light image for a long time, it takes nearly 1200 years to make a scientific explanation of its causes. 1666, Newton made a very simple experiment, but it had a great influence on the later scientific development. He let a beam of sunlight pass through the prism, and finally got seven stripes of red, orange, yellow, green, blue, indigo and purple. This made people realize for the first time that sunlight was originally composed of seven different colors of light. When they pass through the prism, they show their true colors due to the difference in wavelength and refraction. This discovery laid the foundation for the scientific explanation of "halo".

According to research data, this silky white cloud curtain is more than 5000 meters above the ground and consists of small hexagonal columnar ice crystals. If the nonadjacent sides of a hexagonal cylinder are elongated, it is actually a triangular prism. Therefore, hexagonal cylindrical ice crystals can divide sunlight into seven color bars like prisms. On that day, trillions of small ice crystals were irradiated by sunlight, and the light of various colors was refracted at a certain angle, forming a colorful halo.

People are not very interested in "halo" because it is colorful and because it is a precursor to weather changes. According to the statistics of Le Tai, Xinjiang, China, 1980 appeared 1052 "halo", and major weather changes such as wind and rain occurred within two days after the "halo", accounting for 80%.

However, not all "rings" are signs of storms. After long-term observation, meteorologists found that when the duration of "halo" is less than 1 hour (commonly known as "short halo"), there will be wind or rain in the future 12 hours ∽36 hours; When the "halo" lasts more than 5 hours (commonly known as "long halo"), there will be no stormy weather.

The beautiful light ring is the weather forecast map of nature. Understanding and using it to observe the situation can better arrange our lives.

Hope to adopt