What is the name of the process that causes the growth of condensation droplets below the freezing layer (in warm clouds)?

The process that leads to the growth of condensation droplets below the freezing layer in warm clouds is known as collision and coalescence. In warm clouds, temperatures are above freezing, allowing water droplets to exist in liquid form. As these droplets collide with each other, they may stick together and combine to form larger droplets. This process can occur because the droplets can have various sizes and can be influenced by factors such as turbulence within the cloud that enhances the likelihood of collisions.

This mechanism is especially important in the formation of precipitation, as larger droplets are more likely to overcome the updrafts inside the cloud and eventually fall to the ground as rain. In contrast, evaporation and condensation refer to the phase changes of water, which do not specifically address the coalescence aspect needed for droplet growth in clouds. Condensation nucleation describes the initial formation of droplets from vapor but does not pertain to growth through collisions. Condensation deposition involves the direct transition of water vapor to ice, which is not relevant in warm clouds where liquid water droplets are present.