Which element of weather is a measure of how hard the air is pressing down?

The measure of how hard the air is pressing down is referred to as air pressure. Air pressure is the weight of the air above a particular point, and it exerts force on surfaces, influencing various weather patterns. When air pressure is high, it generally leads to clear skies and fair weather, while low air pressure is often associated with clouds and precipitation. Understanding air pressure is crucial in meteorology as it plays a significant role in the movement of air masses and the formation of weather systems.

Precipitation relates to the water that falls from the atmosphere, such as rain or snow, but does not indicate the force of the air. Temperature measures how hot or cold the atmosphere is and affects weather but does not account for the pressure exerted by the air. Cloudiness describes the amount of cloud cover in the sky and is a consequence of various weather elements rather than a measure of pressure. Therefore, the most accurate choice that relates directly to the force exerted by the atmosphere is air pressure.