We call the Earth the blue planet. Photographs from space show a characteristic seen nowhere else in the visible universe.
Water is the foundation of all life on Earth.
The Earth's surface is two-thirds water and experts calculate that the volume is nearly 1.5 billion cubic kilometers. But only about two per cent is freshwater, and nearly all of that is locked in glaciers, ice caps and deep groundwater reservoirs. Only an estimated 2000 cubic kilometres is readily available to meet human needs. As industrial, agricultural and domestic pollution threatens finite supplies, water is becoming an increasingly precious resource. Recent history has witnessed conflict between nations over rights and access to fossil fuel resources.