Vattenkrets

Vattenkrets, often translated as water cycle or hydrological cycle, refers to the continuous movement of water on, above, and below the surface of the Earth. This fundamental process is driven by solar energy and gravity.

The cycle begins with evaporation, where water from oceans, lakes, rivers, and even soil transforms into water vapor and rises into the atmosphere. Transpiration, the release of water vapor from plants, also contributes to atmospheric moisture. As this moist air rises, it cools and condenses, forming clouds through a process called condensation.

When the water droplets or ice crystals in clouds become heavy enough, they fall back to Earth as precipitation in various forms such as rain, snow, sleet, or hail. Once on the ground, precipitation can follow several paths. Some water flows over the land surface as surface runoff, eventually collecting in streams, rivers, and oceans. Another portion infiltrates the soil, becoming groundwater. This groundwater can be stored in aquifers for extended periods or slowly seep back into surface water bodies.

Sublimation, the direct conversion of ice or snow into water vapor without first melting, also plays a role, particularly in colder regions. The water that becomes surface runoff or groundwater eventually returns to the atmosphere through evaporation or transpiration, thus completing the cycle. The continuous circulation of water is essential for life on Earth, shaping landscapes and influencing climate.