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			Jesus is a fat drunkard
	:''This article focuses on water as it is experienced in everyday life. See ] for information on the chemical and physical properties of pure water (H<sub>2</sub>O) (Hydrogen oxide).''

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	'''Water''' (from the ] and ] ''wæter'') is a ]less, ]less, and ]less substance that is essential to all known forms of ] and is the most universal ].

	Water is an abundant substance on ]. It exists in many places and forms: mostly in the ] and polar ]s, but also as ]s, ], ], and ]. On the planet, water is continuously moving through the ] involving ], ], and ] to the ].

	All known forms of ] need water. ] consume "drinking water", water with qualities compatible with the ]. This natural resource has become scarce with the growing ], and its availability is a major social and economic concern.

	==A surprising substance==
	===Changing appearances===
	:''See ]''
	]]]
	Water takes many different shapes on earth: ] and ]s in the sky, ]s and ]s in the ], ]s in the ], ] in the ground, to name but a few. Through ], ] and ], water is continuously flowing from one form to another, in what is called the '''water cycle'''.

	Because of the importance of precipitation to ], and to ] in general, we give different names to its various forms: while ] is common in most countries, other phenomena are quite surprising when seen for the first time: ], ], ] or ] for example. When appropriately lit, water drops in the air can ] the beautiful colours of a ].



	Similarly, water runoffs have played major roles in our history: ]s and ] brought the water needed for agriculture. Rivers and the ]s offered opportunity for travel and commerce. Through ], runoffs played a major part in shaping our environment providing river ]s and ]s which provide rich soil and level ground for the establishment of population centers.

	Water also infiltrates the ground and goes into ]s. This ] later flows back to the surface in ], or more spectacularly in ]s and ]s. Groundwater is also extracted artificially in ]s.

	Because water can contain many different substances, it can taste or smell very differently. In fact, we have developed our senses to be able to evaluate the drinkability of water: we avoid the ]y seas and the putrid ]s, and we like the fresh pure water of a mountain spring.

	===Important properties for living organisms===
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	Water has many unusual properties that are critical for life: it is a good ] and has high ]. Fresh water has its greatest ] at 4°]: it becomes less dense as it ] or ]s up. As a stable, ] prevalent in the atmosphere, it plays an important atmospheric role as an absorber of ], crucial in the atmospheric ]. Water also has an unusually high ], which plays many roles in regulating global climate.

	Water is a very good ] and dissolves many types of substances, such as various salts and ], and facilitates their ], which aids complex ]s.

	Some substances, however, do not mix well with water, including ]s and other ] substances. ]s, composed of ]s and ]s, take advantage of this property to carefully control interactions between their contents and external chemicals. This is facilitated somewhat by the surface tension of water.

	Water drops are stable due to the high surface tension of water. This can be seen when small quantities of water are put onto a nonsoluble surface such as ]: the water stays together as drops. This property plays a key role in ] ].

	A simple but environmentally important and unique property of water is that its common solid form, ], floats on the liquid. This solid phase is less dense than liquid water, due to the geometry of the strong hydrogen bonds which are formed only at lower temperatures. For almost all other substances and for all other 11 uncommon phases of water ice except ice-XI, the solid form is more dense than the liquid form. Fresh water is most dense at 4°C, and will sink by ] as it cools to that temperature, and if it becomes colder it will rise instead. This reversal will cause deep water to remain warmer than shallower freezing water, so that ice in a body of water will form first at the surface and progress downward, while the majority of the water underneath will hold a constant 4°C. This effectively insulates a lake floor from the cold.

	Life on earth has evolved with and fine tuned itself to the important features of water. The existence of abundant liquid, vapor and solid forms of water on Earth has no doubt been an important factor in the abundant colonization of Earth's various environments by life-forms adapted to those varying and often extreme conditions.

	==Importance of astronomical position==
	]
	The coexistence of the solid, liquid, and gaseous phases of water on Earth is perhaps vital to the origin and evolution of life on Earth as we know it. However, if the Earth's location in the ] was marginally closer or further from the ], the conditions which allow the three forms to be present simultaneously would have been more unlikely.

	Earth's mass allows ] to hold an ]. ] and ] in the atmosphere provides a ] which helps maintain a relatively steady surface temperature. If Earth were less massive, a thinner atmosphere would cause temperature extremes preventing the accumulation of water except in ]s (as on ]). According to the ] model of the solar system's formation, Earth's mass may be largely due to its distance from the Sun.

	The distance between Earth and the Sun and the combination of solar radiation received and the greenhouse effect of an atmosphere ensures that its surface is neither too cold nor too hot for liquid water. If Earth were more distant, most water would be frozen. If Earth was nearer to the Sun, its higher surface temperature would limit the formation of ice caps, or cause water to exist only as vapor. In the former case, the low ] of ]s would cause Earth to absorb more solar energy. In the second a runaway ] and inhospitable conditions similar to ] would result.

	It has been proposed that life itself may maintain the conditions that have allowed its continued existence. The surface temperature of Earth has been relatively constant through ] despite varying solar flux, indicating that a dynamic process governs Earth's temperature via a combination of greenhouse gases and surface or atmospheric albedo. See '']''.

	==Water in everyday life==
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	All known forms of life depend on water. Water is a vital part of many ] processes within the body. Significant quantities of water are used during the ] of food. (Note however that some ] and ] ]s can enter a ] for an indefinite period when dehydrated, and come back to life when returned to a wet environment)

	About seventy two percent of the fat free mass of the ] body is made of water. To function properly the body requires between one and seven ]s/]s of water per ] to avoid ], the precise amount depending on the level of activity, temperature, humidity, and other factors. It is not clear how much water intake is needed by healthy people. Water is lost from the body in ] and ], through ]ing, and by exhalation of water ] in the breath.

	Humans require water that does not contain too much salt or other impurities. Common impurities include chemicals or harmful ]. Some solutes are acceptable and even desirable for perceived taste enhancement. Water that is suitable for drinking is termed '''potable water'''.

	Because of the growth of ] and other factors, the availability of drinking water per person is shrinking. This issue can be solved through more production, better distribution, or through less waste.

	===A rare resource===
	:''See ] for information about ] supplies.''
	Water is a strategic resource for many countries. Many battles and wars, such as the ] in the ], have been fought to gain access to it. Experts predict more trouble ahead because of the world's growing ], increasing contamination through ] and ].

	]'s World Water Development Report (WWDR, 2003) from its World Water Assessment Program indicates that, in the next 20 years, the quantity of water available to everyone is predicted to decrease by 30%. 40% of the world's inhabitants currently have insufficient fresh water for minimal ]. More than 2.2 million people died in ] from ]s related to the consumption of contaminated water or ]. In 2004, the ] ] ] reported that a child dies every 15 seconds due to easily preventable water-related diseases.

	Some have predicted that clean water will become the "next ]", making ], with this resource in abundance, possibly the richest country in the world.

	===Water for everyone===
	There are three ways to improve the availability of drinking water: produce it more, distribute it better to the needy, and waste it less.

	Drinking water is often collected at ] or extracted from artificial ]s in the ground, or ]s. Building more wells in adequate places is thus a possible way to produce more water. Other water sources are the rain or the seas. This water however is not adequate for human consumption, and ] is needed. Popular methods for purifying water are ], ] and ]. More advanced techniques exist, such as ].

	The distribution of drinking water is done through ]s or as ]. Governments in many countries have programs to distribute water to the needy at no charge. Others argue that the ] mechanism and ] are best to manage this rare resource, and to finance the boring of wells or the construction of ]s and ]s.

	Reducing waste, i.e. using drinking water only for human consumption, is another option. In some cities, such as ], sea water is extensively used for flushing toilets citywide in order to conserve fresh water resources. ] may be the biggest single misuse of water; to the extent that a pollutant limits other uses of the water, it becomes a waste of the resource, regardless of benefits to the polluter.

	==Water in human culture==
	Water is considered a purifier in most religions, including ], ], ], and ]. For instance, ] in Christian churches is done with water. As well, a ritual bath in pure water is done for the dead in many religions including Judaism and Islam. And in Islam, the daily ] can only be done after ] (]) that is washing parts of the body in clean water. In ], water is used in almost all rituals to cleanse a person or an area.

	Water is often given spiritual powers. In ], ] is the local ] of thermal springs; in ], the ] is also personified as a goddess. Alternatively, gods can be patrons of particular springs, river or lakes: for example in ] and ] ], ] was a river god, one of the three thousand ].

	], a ] ] maintained that water is one of the four ]s along with ], ] and ], and was regarded as the ], or basic stuff of the universe. Water was considered cold and moist. In the theory of the four ]s, water was associated with ]. ] was also one of the ] in traditional ], along with
	],], ], and ].

	== See also ==
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	== External links ==
	{{commons\|water}}
	* A faithful summary by GreenFacts of a leading scientific consensus report on Drinking Water Disinfectants published by the International Programme on Chemical Safety of the WHO.
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	* (SIWI)
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	* - Interesting site providing facts about tap and bottled water.
	* (Oct 2003).
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Revision as of 19:03, 18 May 2005

Jesus is a fat drunkard