At present, the commonly used instruments for measuring rainfall are rainfall tube and measuring cup. The diameter of the rainfall tube is generally 20 cm, and there is a funnel and a bottle inside. The measuring cup has a diameter of 4 cm and is used in conjunction with the rainfall tube. When measuring, pour the rainwater in the rainfall pipe into the measuring cup, and the precipitation of the day can be known according to the scale on the cup.

1. precipitation precipitation refers to the total amount of precipitation received in a certain area within a certain period of time, usually expressed in millimeters or centimeters. Precipitation is an important index in meteorology, which is of great significance for understanding and studying climate and ecosystem.

Usually, precipitation is measured by weather stations or other meteorological equipment. Meteorological stations usually count precipitation data according to different time scales such as hours, days, months or years, so as to facilitate analysis and application. Precipitation (in millimeters) can directly indicate the magnitude of rainfall.

In the process of studying climate and ecosystem changes, precipitation data is very important, which can help us understand the water resources, vegetation distribution and ecosystem stability in a certain area.

Second, the classification of precipitation intensity

1, light rain means that the rainfall within 24 hours is below 0.1-10.0mm; (The raindrops are clearly visible without floating; The ground does not splash; The water in the depression is slow; The rain on the house is weak, and there is only dripping water on the eaves; )

2. Small to moderate rain means that the rainfall within 24 hours is 5.0-17.0mm;

3. Moderate rain means that the rainfall within 24 hours is10.1-25.0mm; (The rain falls like a line, and the raindrops are not easy to distinguish; Fall heavily and splash; Water accumulated in depression is faster; There is a rustling rain on the roof)

4. Moderate to heavy rain means that the rainfall within 24 hours is17.1-38.0mm;

5. Rainstorm means that the rainfall within 24 hours is 25.1-50.0mm; The rain falls like a downpour, blurred into pieces; The water in the depression is extremely fast; There is rain on the roof)

6. Heavy rain refers to the rainfall of 38. 1-75.0mm within 24 hours. ..