The illustration depicts the natural process of water cycle. Overall, it is noticeable that there are three main processes in this diagram; evaporation, rain, and water running back to the sea.
To begin with, owing to the sun's heat, evaporation process occurs from two main places; the sea which stores water, and lakes and rivers. In addition, transpiration from plants and trees also happens because of heat of the sun. After that, the result of evaporation and transpiration becomes invisible water vapor which is brought by wind. The higher wind carries out, the cooler vapor is, then cloud being formed. The next stage is when rain falls because clouds are much cooler.
Turning to the next stage, water from rain, then, flows on the river and some passes into the porous rock being ground water which flows into lakes, rivers, and seas. Afterwards water from river flows into the sea.