How is precipitation typically measured?

Precipitation measurement is most commonly expressed in millimeters or inches of liquid water depth because these units quantify the depth of water that accumulates on a flat surface as a result of rain, snow, or other forms of moisture. This method provides a direct way to understand how much water is being deposited onto the ground, which is crucial for hydrological studies, agriculture, water resource management, and understanding weather patterns.

Using millimeters or inches allows for a clear and standardized way to communicate precipitation amounts, which can easily be compared across different geographical locations and time periods. Depth measurements are particularly useful in assessing the potential impact of rainfall on soil saturation, runoff, and overall water availability in an area.

The other units presented in the question do not accurately represent precipitation. Liters measure volume but do not convey how that water is distributed over a surface area. Kilograms refer to mass and would not provide useful information about the depth of water. Degrees Celsius, on the other hand, measures temperature and is unrelated to precipitation measurements.