Water is one of the Earth's most important resources. The Earth is the only known planet where water exists in all three states; solid, liquid, and gas.  

In fact, water makes up the majority of the Earth’s surface, with over 70% of the Earth covered in water. Incredibly, 97.5% of the Earth’s water is found in the ocean. The remaining 2.5% of freshwater is found in lakes and rivers (0.3%), glaciers and permanent ice (68.9%), and groundwater (30.8%).

Water on earth is vital for the survival of all ecosystems, from the dense forests of the Amazon, to the deserts of the Sahara, and even in the harsh Antarctic environment. It Is even understood that all life began in the ocean. The availability of water as a resource drives population distribution and species adaptation. This is true not only for the animals and plants who live within the environment, but also for human populations for which access to water is a vital resource. Oceans provide not only a food source for coastal populations, but are central in many primary industries including fishing and transportation.

The Earth’s water is constantly moving throughout the planet, connecting us all in a process known as the hydrological cycle. The hydrological cycle involves the movement of water as it changes state. The evaporation and evapotranspiration of water from land and the ocean, moves water vapour into the atmosphere where it condensates forming clouds. Water from the atmosphere precipitates back to the land and ocean in the form of rain or snow, where it forms rivers, streams, lakes and glaciers, or becomes groundwater. Water is also consumed and expelled by plants, animals and humans. Over time, the hydrological cycle transports and transfers water across the planet.