Why does hot air only rise?

Hot air only rises because of the temperature difference caused by uneven heating, and the rise of hot air is very light.

When air is heated by a heat source, its volume expands and its density decreases, and the density of cold air around it remains unchanged, resulting in a pressure difference, which is easy to make hot and cold air flow. The proportion of hot air is small and rising, and the proportion of cold air is large and sinking, forming convection.

The generation of hot air is influenced by various weather, temperature, humidity, temperature drop rate, surface temperature difference, air pressure and other data. Generally speaking, the greater the temperature drop rate, the more abundant the sunshine and the drier the air, which is more conducive to the formation of hot air.

Extended data:

The air mass in the atmosphere moves vertically upward under the action of heat or power. On the one hand, atmospheric convection can produce the exchange of heat, momentum and water vapor between the lower and upper atmosphere, on the other hand, the condensation of water vapor caused by convection may produce precipitation.

In the unstable stratified atmosphere, a mass of air is less dense than ambient air under the action of heat, so its buoyancy is greater than gravity, and it forms an upward movement under the action of Archimedes buoyancy.

On the one hand, thermal action can form atmospheric convection, on the other hand, atmospheric convection can affect the thermal and dynamic structure of the atmosphere, which is the feedback effect of atmospheric convection. In the tropical region where the atmosphere is located, this feedback effect is particularly important, and the condensation and heating of water vapor formed by atmospheric convection is often an important energy source for large-scale atmospheric movement in this region.

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