Earth's water resources

About 71% of the Earth's surface is covered by water, but 97.5% of it is saltwater and only 2.5% is freshwater. In this limited freshwater resource, most of it still exists in the form of glaciers and permafrost, and the actual freshwater resources available for human use account for only 0.3% of the total global water volume. Therefore, each of us should take action to conserve water, protect water sources, and jointly safeguard the precious water resources on Earth.

The unit is designed for unsupervised public use: controls are recessed or shielded, moving parts are enclosed, and the interface is operable by a child of about six with no instruction. Where a screen is used, the language can be switched without changing the hardware, and the content can be replaced on site.

The distribution of Earth's water: 96.53% is ocean water, 0.013% is land water (river water 0.0002%, lake water 0.013%, groundwater 1.69%, glacier water 1.74%), and 0.001% is atmospheric water. The freshwater mainly used by humans is rivers, lakes, and shallow groundwater. About two-thirds of the rain and snow water that falls to the ground is consumed by plant transpiration and ground evaporation, providing approximately 10000 cubic meters of freshwater resources per person per year for human life and production. However, due to the disproportionate distribution of population and freshwater resources on Earth, coupled with water pollution and waste during use, many countries and regions in the world are facing a shortage of freshwater resources. Many countries and regions are willing to set up seawater desalination facilities or take other measures at high cost to alleviate the contradiction in freshwater supply. With the continuous development of the economy, people's demand for freshwater is constantly increasing. By 2025, the scarcity of freshwater resources will become a serious problem faced by countries around the world.