Hi Tech & Innovation

'Flying' river taxi tests Seine waters in Paris

A "flying" electric river taxi hailed by its creators as the future of clean city transport is being put through a battery of tests in Paris this week, with a view to being in service by the spring.

Energy & Green Tech

Ocean power: A green option failing to make waves

The tidal power plant on the Rance river in Brittany, France, stands as a reminder of the underexploited potential of energy generation from ocean tides, waves and warmth.

Energy & Green Tech

Algae and bacteria team up to increase hydrogen production

In line with the fight against climate change and the search for a sustainable future, there is the idea of a future society based on hydrogen used as a fuel. This biofuel of the future could be what cars and engines run ...

Energy & Green Tech

Future maps: We have the blueprint for livable, low-carbon cities

Over the past seven years more than 100 research projects at the Co-operative Research center for Low Carbon Living, in collaboration with industry across Australia, have pondered a very big question: How do we build future ...

Engineering

Water harvester makes it easy to quench your thirst in the desert

In 2017, UC Berkeley chemists demonstrated that a new MOF design could rapidly adsorb water from even dry air, allowing it to be condensed and collected for drinking. A second-generation MOF can now cycle through adsorption ...

Engineering

Researchers flip how electrical signals move liquid droplets

When medical laboratories analyze blood samples for signs of disease, they sometimes use instruments that rely on a technology called digital microfluidics. The technique uses electric signals to pull tiny droplets of the ...

Engineering

Using a smartphone to detect norovirus

A little bit of norovirus—the highly infectious microbe that causes about 20 million cases of food poisoning in the United States each year—goes a long way. Just 10 particles of the virus can cause illness in humans. ...

Consumer & Gadgets

Researchers find smart faucets could aid in water conservation

Barely hidden from his study participants, William Jou, a former graduate student in mechanical engineering at Stanford University, pulled off a ruse straight out of The Wizard of Oz. Except, instead of impersonating a great ...

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Water

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