Energy & Green Tech

Can we coordinate water sources to recover more water sustainably?

In many places, including Southern California, climate change has increased the threat of drought and the need for new and continuous water resources. Higher salinity water streams, and sometimes seawater, come into consideration ...

Energy & Green Tech

Is it sensible to use rainwater to flush the toilet?

As a world first, a new residential district in Aarhus is using secondary water from the local water utility for toilets and washing machines. The solution is supported by a life cycle assessment.

Energy & Green Tech

Operator: Impact from release of Fukushima water minimal

The operator of the tsunami-wrecked Fukushima nuclear power plant said Wednesday that a data simulation of its planned release of treated radioactive water into the sea suggests it would have an extremely small impact on ...


City OKs Google data centers amid secrecy, water worries

The council of a small Oregon city has approved a deal with Google that will enable the technology giant to build two more water-guzzling data centers there, though some residents worry about drought and secrecy.

Energy & Green Tech

Electric vehicles could be powered by hydrogen harvested from sewage

Wastewater treatment is vital to remove pathogens, but is incredibly energy intensive. The ability to treat it more sustainably is a challenge researchers from WMG, University of Warwick have been able to achieve, using recycled ...

Energy & Green Tech

In Iceland, CO2 sucked from the air is turned to rock

At the foot of an Icelandic volcano, a newly-opened plant is sucking carbon dioxide from the air and turning it to rock, locking away the main culprit behind global warming.

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Water is a ubiquitous chemical substance, composed of hydrogen and oxygen, that is essential for the survival of many known forms of life. In typical usage, water refers only to its liquid form or state, but the substance also has a solid state, ice, and a gaseous state, water vapor or steam. Water covers 71% of the Earth's surface. On Earth, it is found mostly in oceans and other large water bodies, with 1.6% of water below ground in aquifers and 0.001% in the air as vapor, clouds (formed of solid and liquid water particles suspended in air), and precipitation. Saltwater oceans hold 97% of surface water, glaciers and polar ice caps 2.4%, and other land surface water such as rivers, lakes and ponds 0.6%. A very small amount of the Earth's water is contained within biological bodies and manufactured products. Other water is trapped in ice caps, glaciers, aquifers, or in lakes, sometimes providing fresh water for life on land.

Water moves continually through a cycle of evaporation or transpiration (evapotranspiration), precipitation, and runoff, usually reaching the sea. Winds carry water vapor over land at the same rate as runoff into the sea. Over land, evaporation and transpiration contribute to the precipitation over land.

Clean, fresh drinking water is essential to human and other lifeforms. Access to safe drinking water has improved steadily and substantially over the last decades in almost every part of the world. There is a clear correlation between access to safe water and GDP per capita. However, some observers have estimated that by 2025 more than half of the world population will be facing water-based vulnerability. Water plays an important role in the world economy, as it functions as a solvent for a wide variety of chemical substances and facilitates industrial cooling and transportation. Approximately 70 percent of freshwater is consumed by agriculture.

This text uses material from Wikipedia, licensed under CC BY-SA