Hot air is less dense than cold air, which is why hot air rises and cold air sinks, according to the United States Department of Energy. Hot and cold air currents power the weather systems on earth. … Warm air currents typically bring rain, because they form over oceans.

Does warm air rises or sink?

The movement of hot and cold air is very important for moving heat and energy around our planet Earth. Hot air is less ‘dense’ than cold air. In case you do not know the word ‘dense’ yet, I essentially mean that hot air is lighter and cold air is heavier. Therefore, hot air rises and cold air sinks.

What happens as warm air rises?

If warm moist air rises, it will expand and cool. As it cools, the relative humidity will increase and water will condense. It can then fall back to the earth as precipitation. … As air rises, it expands because there is less atmospheric pressure at higher altitudes.