What does air temperature measure?

Air temperature measures the degree of hotness or coldness of ambient air. This is quantified using various scales, such as Celsius or Fahrenheit, which reflect how kinetic energy of air molecules corresponds to temperature values. Higher temperatures indicate greater molecular motion and energy, while lower temperatures indicate less motion and energy. Understanding air temperature is fundamental for various applications, including weather forecasting, aviation, and environmental studies, as it can affect weather patterns, precipitation, and humidity levels.

The other choices focus on different atmospheric properties: humidity refers to the moisture content in the air; air pressure indicates the force exerted by the weight of air molecules in a given area; and altitude pertains to the height above sea level of the atmospheric layer, which can influence temperature but is not what temperature itself measures.