lhydrosphère

The hydrosphere is the total amount of water on a planet. It includes water on the surface, underground, and in the air. On Earth, it is estimated that 96.5% of all water is contained within the hydrosphere. This includes water in oceans, lakes, rivers, groundwater, glaciers, ice sheets, and atmospheric water vapor.

The hydrosphere plays a crucial role in regulating Earth's climate and supporting life. Water is essential for all known forms of life and is a vital component of many biological processes. The distribution of water across the planet is not uniform. Oceans hold the vast majority of Earth's water, followed by glaciers and ice caps, then groundwater. Surface water bodies like lakes and rivers, along with atmospheric water, make up a smaller but significant portion.

The water cycle, also known as the hydrologic cycle, describes the continuous movement of water on, above, and below the surface of the Earth. This cycle involves processes such as evaporation, transpiration, condensation, precipitation, and surface runoff. These processes ensure that water is constantly recycled and distributed across the globe. Changes in the hydrosphere, such as sea-level rise or altered precipitation patterns, can have profound impacts on ecosystems and human societies. Understanding the hydrosphere is therefore fundamental to comprehending Earth's climate system and its habitability.