What percentage of the hydrosphere is made up of salt water?

The hydrosphere consists of all the water on Earth, which can be found in oceans, rivers, lakes, and glaciers. Approximately 97.5% of the hydrosphere is composed of salt water, primarily found in the Earth's oceans. This high percentage emphasizes how the vast majority of Earth's water is saline, making fresh water relatively scarce. Freshwater sources, such as rivers, lakes, and groundwater, account for only about 2.5% of the total hydrosphere, with the majority of that being locked within glaciers and ice caps or not readily accessible. Understanding this distribution is crucial for comprehending global water resources, environmental management, and the challenges surrounding freshwater scarcity.