Answer:
Water enters the atmosphere through evaporation, transpiration, excretion and sublimation:
Transpiration is the loss of water from plants.
Animals excrete water by respiration and by passing urine.
Sublimation is when ice or snow transforms directly into water vapor without going through a liquid phase.
Step-by-step explanation:
Water commonly occurs in the atmosphere in the form of water vapor. If it cools down, it can condense, accumulating in clouds. As the clouds grow, they become heavier and can fall back to the Earth as precipitation or re-evaporate back into vapor.