What is defined as the temperature at which air becomes saturated, leading to condensation?

The temperature at which air becomes saturated, leading to condensation, is known as the dew point. When the air temperature reaches the dew point, the air is holding as much moisture as it can at that temperature. Any further cooling of the air will result in excess moisture condensing into liquid water, commonly seen as dew, fog, or clouds.

Understanding the dew point is essential in meteorology and physical geography because it indicates humidity levels in the atmosphere. For example, higher dew points suggest that the air is more humid, while lower dew points indicate drier air. This concept is crucial in predicting weather patterns and understanding climate conditions.

Relative humidity, while related, expresses the current humidity level compared to the maximum at a specific temperature, making it a different measure. The terms "heating point" and "condensation point" are less commonly used in this context and do not accurately capture the phenomenon of saturation leading to condensation.