Because sunlight is absorbed mostly by solid objects (not the gasses of the atmosphere),
so the ground heats up, and warms the air adjacent to it.
The atmosphere is more heated from below because the air is thicker the farther down you go, and so it traps the heat in the air.
Convection currents
Cool Air! As the heated air rises the heated air starts getting cool. This is because the higher the air is the colder it gets. Then the heated air will be replaced with cold air. As the cold air then comes down near the ground the cool air will become heated because of the sun. Heated Air - Cool Air - Cold Air And On And On It Goes
Air expands when it is heated.
when air is heated ,air pressure decreases because the molecules are
If there is no fan to pull the air in, fresh air must come into a convector heater from below. It is drawn in because the air heated by the heating element is warmer and therefore lighter than the colder air below it. So the warmer air rises to leave the convector heater from the top.
air gets heated with carben dioxid and the rays of the sun
Heat. As the air expands (as it's heated), it rises and causes air to flow upward.
the air being heated from a fireplace,air from a furnace,boiling water,the air being heated in a hot air balloon.
The density of heated air is less than the density of cooler air.
There are a few causes that lead to atmospheric air to be rapidly heated. Having a fire burning will lead to rapidly heated atmospheric air.
Currents that form in heated air are similar to currents that form in warm water because heated air goes up and cold air goes down creating convection currents.