Water

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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.

For more information about Water, read the full article at Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.


News tagged with water

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LCROSS Impact Data Indicates Water on Moon

LCROSS Impact Finds Water on the Moon

Space & Earth / Space Exploration

created Nov 13, 2009 | popularity 4.9 / 5 (31) | comments 15

(PhysOrg.com) -- The argument that the moon is a dry, desolate place no longer holds water. Secrets the moon has been holding, for perhaps billions of years, are now being revealed to the delight of scientists ...


H1N1 Virus Can Be Killed by Acidic Ozone Water

H1N1 Virus Can Be Killed by Acidic Ozone Water

Chemistry / Biochemistry

created Nov 09, 2009 | popularity 4.5 / 5 (44) | comments 16

(PhysOrg.com) -- Scientists have found that acidic ozone water can deactivate H1N1 viruses very effectively, offering a promising disinfectant for the millions of people trying to avoid the disease. Acidic ...


The creature was found at a depth of 161 metres

Japanese researchers film rare baby fish 'fossil'

Biology / Plants & Animals

created Nov 17, 2009 | popularity 4.7 / 5 (7) | comments 4

Japanese marine researchers said Tuesday they had found and successfully filmed a young coelacanth -- a rare type of fish known as "a living fossil" -- in deep water off Indonesia.


MIT scientists pinpoint origin of dissolved arsenic in Bangladesh drinking water

Scientists pinpoint origin of dissolved arsenic in Bangladesh drinking water

Space & Earth / Environment

created Nov 15, 2009 | popularity 4.8 / 5 (21) | comments 1

Researchers in MIT's Department of Civil and Environmental Engineering believe they have pinpointed a pathway by which arsenic may be contaminating the drinking water in Bangladesh, a phenomenon that has puzzled ...


New explanation for nature's hardiest life form

Biology / Cell & Microbiology

created Nov 12, 2009 | popularity 4.3 / 5 (8) | comments 0

Got food poisoning? The cause might be bacterial spores, en extremely hardy survival form of bacteria, a nightmare for health care and the food industry and an enigma for scientists. Spore-forming bacteria, present almost ...


Earth's early ocean cooled more than a billion years earlier than thought: Stanford study

Earth's early ocean cooled more than a billion years earlier than thought (w/ Video)

Space & Earth / Earth Sciences

created Nov 11, 2009 | popularity 4.3 / 5 (12) | comments 1

(PhysOrg.com) -- The scalding-hot sea that supposedly covered the early Earth may in fact never have existed, according to a new study by Stanford University researchers who analyzed isotope ratios in 3.4 ...


Tadpoles Used to Rapidly Detect Water Pollution

Space & Earth / Environment

created Dec 03, 2009 | popularity 2 / 5 (2) | comments 1

(PhysOrg.com) -- Research conducted by University of Wyoming Professor Paul Johnson and others demonstrates that genetically modified tadpoles work well as sensitive monitors for rapidly detecting water pollution.


Loves Me, Loves Me Not: Researchers Discover New Method for Measuring Hydrophobicity at the Nanoscale

Loves Me, Loves Me Not: Researchers Discover New Method for Measuring Hydrophobicity at the Nanoscale

Nanotechnology / Nanophysics

created Dec 03, 2009 | popularity not rated yet | comments 0

(PhysOrg.com) -- Researchers at Rensselaer Polytechnic Institute have discovered a new, more precise method for measuring how much — or how little - nanoscale interfaces love water.


Fish with attitude: Some like it hot

Biology / Plants & Animals

created Dec 03, 2009 | popularity not rated yet | comments 0

Coral reef fish can undergo a personality change in warmer water, according to an intriguing new study suggesting that climate change may make some species more aggressive.


A light touch: Iron complexes as efficient catalysts for the light-driven extraction of hydrogen from water

Chemistry / Materials Science

created Dec 02, 2009 | popularity 5 / 5 (4) | comments 3

(PhysOrg.com) -- Hydrogen is a promising alternative energy carrier that can be efficiently converted into electrical energy in fuel cells. One hurdle to the introduction of sustainable hydrogen technology is the fact that ...


INL develops safer, more efficient nuclear fuel for next-gen reactors

INL develops safer, more efficient nuclear fuel for next-gen reactors

Technology / Energy

created Nov 30, 2009 | popularity 4.5 / 5 (15) | comments 7

As the nation ponders its energy choices, Americans keep asking themselves: how can the country make better use of its resources and emit fewer greenhouse gases without hurting U.S. industries? A research ...


Fast, easy, and highly sensitive arsenic detection with gold nanoparticles

Nanotechnology / Nanomaterials

created Nov 25, 2009 | popularity 5 / 5 (1) | comments 0

(PhysOrg.com) -- Mention of arsenic poisoning usually brings to mind underhanded murder. However, the danger of arsenic poisoning from contaminated drinking water is far greater. Low concentrations of arsenic are found in ...


Asian carp may have breached barrier protecting Lake Michigan

Biology / Ecology

created Nov 24, 2009 | popularity 5 / 5 (5) | comments 0

Two feared species of Asian carp have zoomed beyond the $9 million electric barriers built to keep them out of Lake Michigan. Now, the only thing left between the carp and the Great Lakes is a lock and dam in southern Chicago.


The drying shores of the Dead Sea

Dead Sea needs world help to stay alive

Space & Earth / Environment

created Nov 24, 2009 | popularity 3.8 / 5 (6) | comments 3

The Dead Sea may soon shrink to a lifeless pond as Middle East political strife blocks vital measures needed to halt the decay of the world's lowest and saltiest body of water, experts say.


Some 6,000 families were affected by the drought in the Chaco region of Paraguay, particularly indigenous populations

El Nino intensifies Latin America drought

Space & Earth / Earth Sciences

created Nov 20, 2009 | popularity 5 / 5 (2) | comments 0

From a devastating food crisis in Guatemala to water cuts in Venezuela, El Nino has compounded drought damage across Latin America this year.