The diagram illustrates the water cycle, showing how water transforms through different stages, including evaporation, condensation, precipitation, and surface runoff, and how it moves through various parts of the environment.
The process begins with water evaporating from the surface of oceans, which contributes about 80% of the total water vapor in the atmosphere. As the water vapor rises, it cools and condenses into clouds. When these clouds accumulate enough moisture, precipitation occurs, causing water to fall back to Earth in the form of rain, snow, or hail.
Once the water reaches the ground, it is stored in various forms. Some of it is stored as snow in mountainous regions, while other portions collect in lakes or rivers. Water that falls in higher elevations moves downhill as surface runoff, contributing to streams and rivers. A portion of the water seeps into the ground, replenishing groundwater supplies. The water that is not absorbed by the soil flows over the impervious layer beneath the ground and eventually returns to the ocean. Additionally, some groundwater may pass through the process of saltwater intrusion when it mixes with ocean water.
Finally, the cycle continues as heat from the sun causes more water to evaporate from the ocean, starting the process all over again.