Final answer:
Water in the atmosphere exists as water vapor, an invisible gas resulting from evaporation or sublimation, whereas water in clouds is condensed into tiny visible droplets or ice crystals that can lead to precipitation.
Step-by-step explanation:
The water in the atmosphere typically refers to water vapor, which is water in its gaseous state. Water vapor enters the atmosphere through the processes of evaporation and sublimation, where it is warmed by the sun's energy and transformed from liquid or solid states into gas. When this water vapor rises, cools, and condenses, it forms clouds as tiny droplets of liquid water or as ice crystals if the temperatures are sufficiently low. Hence, clouds represent a condensed form of atmospheric water and can lead to precipitation when the droplets combine and become heavy enough to fall back to the surface as rain, snow, sleet, hail, or freezing rain.
While water vapor is invisible and uniformly distributed in the air, clouds are visible accumulations of water droplets or ice crystals, depending on the temperature and pressure conditions in the atmosphere. Condensation is crucial for cloud formation and is influenced by the rising air currents that carry the water vapor into higher, cooler parts of the atmosphere. In contrast, the dispersed water vapor can remain in the atmosphere until it undergoes condensation or moves as part of the global water cycle, eventually returning to land or sea.