Rainfall Monitoring Stations: Principles and Applications of Major Rain Gauge Types

With the arrival of the rainy season, frequent rainfall is prone to triggering geological disasters such as floods and landslides, posing a huge threat to people's lives and property safety as well as social and economic development. In order to timely grasp the rainfall situation, scientifically prevent disasters, and accurately monitor rainfall, precise rainfall monitoring has become a very important task. Rainfall monitoring stations can collect and transmit rainfall data in real time and accurately, providing real-time data for flood control and drought relief, water resource allocation and other work.

Rainfall monitoring stations realize rainfall monitoring by carrying a variety of sensors, mainly including Stainless Steel Tipping Bucket Rain Gauge, radar rain gauge, piezoelectric rain gauge and Optical Rain Gauge.

Stainless Steel Tipping Bucket Rain Gauge is a relatively common rainfall monitoring device. It consists of a rain receiver, funnel, tipping bucket, counting device and other parts. Rainwater enters the funnel through the rain receiver. When one side of the tipping bucket receives a certain amount of rainwater, the tipping bucket will tip over, pour out the rainwater, and at the same time trigger the counting device to record once. By calculating the number of tip-overs of the tipping bucket, the amount of rainfall can be obtained.

Radar rain gauges use electromagnetic waves to detect rainfall. They emit electromagnetic waves into the air. When the electromagnetic waves encounter raindrops, they will be reflected. The radar receives the reflected electromagnetic waves and calculates the size, speed and number of raindrops based on the changes in the signal, and then infers the rainfall. Radar rain gauges have a wide monitoring range and can real-time obtain rainfall information over large areas.

Piezoelectric rain gauges work based on the piezoelectric effect. When raindrops hit the surface of the sensor, they generate pressure, causing the piezoelectric material to deform, thereby generating an electrical signal. By analyzing and processing the electrical signal, the amount of rainfall can be calculated. This type of rain gauge has a fast response speed and high measurement accuracy.

Optical Rain Gauges use optical principles for rainfall monitoring. They detect raindrops by transmitting and receiving light signals. When raindrops pass through the light's propagation path, they block part of the light, causing a change in the intensity of the light signal received by the receiving end. Based on the change in the intensity of the light signal, the amount of rainfall can be calculated. Optical Rain Gauges have the characteristic of non-contact measurement and are less susceptible to external environmental interference.