How is lightning formed when it rains?

Formation of thunder and lightning: when the weather is hot and humid, the water on the ground is heated and turned into steam, which rises with the heated air on the ground and meets the cold air in the air, so that the rising steam condenses into small water droplets and forms cumulus clouds. The water droplets in the cloud are blown up by the powerful airflow and split into some small water droplets and large water droplets. Larger water droplets are positively charged and smaller water droplets are negatively charged. Small water droplets gather with the wind to form a negatively charged Lei Yun; Larger water droplets with positive charges often fall to the ground to form rain or suspend in the air. Due to electrostatic induction, negatively charged Lei Yun induces a positive charge on the earth's surface. In this way, a large capacitance is formed between Lei Yun and the earth. When the electric field intensity is very large and exceeds the breakdown intensity of the atmosphere, a discharge occurs between Lei Yun and the earth, which is generally called the formation of lightning. There are many opinions:1; Discharge phenomenon caused by two large clouds with different charges. 2. It is caused by positive and negative electricity between clouds. American scientists believe that X-rays and gamma rays are the main causes of lightning.

It is generally believed that lightning is formed by the action of electric field in the atmosphere. However, Joseph Dwyer, an astrophysicist from Florida Institute of Technology, said that the theory that the electric field in the atmosphere produces lightning is wrong, and it is impossible for the electric field in the atmosphere to reach the intensity of the electric field that produces lightning. Dwyer studies energetic particles. He came to the Florida Research Center two years ago. At the Florida Research Center, there are many researchers engaged in lightning research. When dwyer learned from academic reports that gamma rays and X-rays are closely related to the formation of lightning, he became interested in it and devoted himself to the research in this field. Many scientists believe that when a strong electric field is formed in the atmosphere, lightning will be produced. Although no one really saw such an electric field, these scientists are still convinced that this is the correct explanation for the formation of lightning. When dwyer established a high-energy radiation model to describe the formation of electric field in the earth's atmosphere, he was shocked by the experimental results of the model. He found that the energy released by gamma rays and X rays in the electric field can provide enough electric field strength for the electric field, thus generating lightning. In thunderstorm weather, updraft and downdraft push water molecules to interact, releasing electrons to enhance the electric field strength, and these electrons eventually spread in the air at a speed close to the speed of light. According to dwyer's theory of lightning formation, these high-speed electrons collide with other particles in the atmosphere under the action of energy released by gamma rays or X rays in the electric field, producing powerful thunder and releasing charges. Martin Uman of the University of Florida, who is committed to the study of lightning formation, said, "This discovery may be a major breakthrough in scientific theory. Dwyer's theory also shows the intensity of gamma rays and X rays needed to generate lightning. " However, the exact explanation of the formation of lightning is still inconclusive. At present, dwyer still speculates that the electric field under certain conditions can gather enough electric field intensity to produce lightning and wind: in nature, there are different winds in different regions and seasons, but the winds are all formed by airflow. In coastal areas, there is sea breeze during the day and land breeze at night. This is because the sun shines on the earth, the temperature on the land is higher than that on the sea during the day, the hot air on the land keeps rising, and the cold air on the sea keeps flowing to the land to replenish it. This air flow from the ocean to the land forms the sea breeze. At night, the temperature on the land drops rapidly, and the temperature on the sea drops slowly, so the temperature on the sea is higher than that on the land, so the cold air on the land flows to the sea to supplement it, forming a land wind. In the mountains, there is also a mountain valley wind. During the day, after the sun comes out, the sun shines on the hillside, the temperature of the air layer near the hillside rises, the hot air keeps rising along the hillside, and the cold air rises from the valley to the top of the mountain to replenish it. This top-down airflow forms the mountain valley wind. At night, the sun has set, and the top of the mountain and the hillside soon get cold. Therefore, a thin layer of air near the top of the mountain and the hillside cools very quickly, while the air accumulated in the valley is still warm. At this time, the cold air near the top of the mountain and the hillside flows to the bottom of the valley, forming a valley wind. Southeasterly winds blow in summer and northwest winds blow in winter in most parts of China. This is because China faces the Pacific Ocean to the east, and it is exposed to the sun in summer. The temperature of the mainland is higher than that of the ocean, and the cold air flows from the ocean to the mainland, so the southeast wind blows. In winter, the temperature of the mainland is lower than that of the ocean, and the cold air from the mainland flows to the ocean, so the northwest wind blows more. Whether it is sea breeze, land breeze, valley breeze, northwest breeze or southeast breeze, it is the sun's irradiation that makes the atmosphere on the earth flow. Formation of rain: Clouds composed of liquid water droplets (including supercooled water droplets) are called water clouds. If the conditions for cloud droplets to grow into raindrops are met in the water cloud, and the raindrops have a certain falling speed, then it is rain or Mao Mao rain that falls. Clouds composed of ice crystals are called ice cloud, and clouds composed of water droplets (mainly supercooled water droplets) and ice crystals are called mixed clouds. Ice crystals or snowflakes falling from ice cloud or mixed clouds fall into the gas layer above 0℃, and after melting, they also fall to the ground as raindrops, forming rainfall.

In the process of rain formation, large water droplets play an important role. When the radius of water droplets increases to 2-3 mm, it is difficult to maintain such a large water droplet by the attraction between water molecules, and it is easy to be split by the impact of airflow on the way down, through a "chain reaction." Make big water droplets fall, and small water droplets continue to exist, forming new big water droplets. This is an important reason for the formation of rain in water clouds and mixed clouds with strong updraft.