Rainfall
The best form of measuring rainfall is by using a tipping bucket rain gauge. This tipping bucket mechanism is adjusted to tip when a predetermined amount of water (usually 0.2mm) has collected in one side of the bucket. The mechanism consists of a divided bucket pivoted at its centre. Rain collects in the upper half. When this is full, the mechanism tilts and discharges the collected water allowing the other half of the bucket to begin filling. When the bucket tips, a message is sent back to the recorder, which then calculates the amount of rainfall.