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Lifting by Convection
upward moving thermals
In meteorology, convection refers primarily to atmospheric motions in
the vertical direction.
||As the earth is heated by the sun, bubbles of hot air (called thermals)
rise upward from the warm surface.
A thermal cools as it rises and becomes diluted as it mixes
with the surrounding air, losing some of its
buoyancy (its ability to rise).|
An air parcel will rise naturally if the air within the parcel is
warmer than the surrounding air (like a hot air balloon).
Therefore, if cool air is present aloft with warm air at
lower levels, thermals can rise to great heights
before losing their buoyancy.