Why is most of Earth’s freshwater unavailable for direct use?

While Earth has an abundance of water, most of it is unavailable for direct human use due to its chemical composition or physical state. Approximately 97 percent of the planet's water is held in oceans, where high concentrations of dissolved minerals and salts make it unfit for drinking, agriculture, or most industrial applications.12

Of the remaining fresh water, the vast majority is inaccessible because it is locked in ice caps, glaciers, and permanent snow, primarily at polar latitudes. Much of the remaining fresh water exists as groundwater stored deep within soils and rocks, which can be difficult or expensive to extract.123

Furthermore, while fresh water is sufficient to meet human needs, it is not uniformly distributed across the globe, and its availability is often compromised by pollution from human activities, such as industrial growth and agricultural runoff. Consequently, less than 1 percent of Earth's total water occurs in lakes and rivers, which are the most accessible sources for human consumption.241