Definition of terms
On the one hand, the exchange of heat, momentum and water vapor between the lower and upper levels of the atmosphere can be generated through atmospheric convection, and on the other hand, the condensation of water vapor caused by convection may produce precipitation. Atmospheric convection under thermal action mainly refers to the rising movement formed under the effect of net Archimedean buoyancy in the stratified unstable atmosphere, where the density of a mass of air is less than that of the ambient air, so it is subject to more buoyancy than gravity. The precipitation of small range, short time, sudden and formed by cumulonimbus clouds often seen in summer is often caused by atmospheric convection under thermal action. The atmospheric convection under dynamic action mainly refers to the upward movement formed under the condition of horizontal convergence of air flow or terrain. Large scale precipitation in the atmosphere is often caused by the horizontal convergence and uplift of the front and the associated air flow, while the precipitation in the fixed area near the mountains is often caused by the forced uplift of the terrain. The atmospheric convection formed by some special terrain (such as trumpet shaped terrain) has both the role of terrain uplift and the role of terrain in horizontal convergence of air flow.
On the one hand, thermal and dynamic effects 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. This feedback is particularly important in the tropical region where the atmosphere is located. The condensation heating of water vapor formed by atmospheric convection is often an important energy source for the large-scale atmospheric movement in this region.
