水循环及回流路径Water cycle: describe the return routes

The diagram illustrates selected routes by which water circulates between the ocean, the atmosphere and the land in a coastal setting. It shows evaporation, cloud formation and rainfall, together with two routes through which water returns to the ocean. Overall, ocean water enters the atmosphere as vapour and returns as rain, either directly over the ocean or indirectly via surface runoff and rivers on land. The two return routes join at the ocean, from which evaporation can occur again. Taking the ocean as a starting point, liquid water evaporates with energy supplied by the sun. The resulting water vapour cools and condenses, forming clouds. Precipitation then falls in the form of rain. No machinery or human intervention is indicated in these natural processes. Rain that falls over the ocean returns water directly to it. In the land route shown, surface runoff enters rivers, which carry the water towards the ocean. Water can subsequently evaporate again, continuing the cycle. The diagram gives neither the proportions following each route nor the time required for the water to return.