How does air move and change in convection currents in the atmosphere?
Convection normally takes place the form of localized air currents rising more or less vigourously while the compensating downward-flow is spread over a large area as a gradual sinking of airmass in the atmosphere.This causes thorough mixing of the various layers of air affected by the convection resulting in the redistribution of temperature and humidity conditions. The upward currents are the cause of the impulsive uplift experienced by aircraft flying into them, known as bumpiness.Above the condensation level,the rising currents are rendered visible by the formation cumulus clouds within them.If the atmosphere is fairly dry,the rising convection currents are known as thermals.If the upward movement is violent,thunder clouds(cumulonimbus) are formed. Convection could never penetrate far above the tropopause as the atmosphere becomes stable there and will not allow the convection to take place.
