Water Cycle

Water, the elixir of life, a common everyday liquid that surrounds us but is more precious than the rarest of gems. Without water life as we know it would cease to exist and yet there is so much water around us that we take it for granted. So, how is it that we continue to have water available even though it has been used by countless living entities since the beginning of life on out earth? The Answer is whats called the water cycle http://ga.water.usgs.gov/edu/watercyclesummary.html or hydrologic cycle http://www.und.edu/instruct/eng/fkarner/pages/cycle.htm the method by which the earths water is continuously recycled. http://www.edwardsaquifer.net/treatme.html

The Water (or Hydrologic) cycle has no real beginning or ending it is a continuous cycle that repeats over and over but for our purpose we will begin with the ocean. The ocean itself is full of water mixed with salt and other minerals. Life as we know it for most of the worlds indigenous land creatures, including humans would not be sustained by salt water. So we have to get the salt out of the water so it can be used by us. http://hyperphysics.phy-astr.gsu.edu/HBASE/Chemical/seawater.html The answer is evaporation. The sun heats the water in the ocean to the point where some of it vaporizes and escapes into the atmosphere. http://ga.water.usgs.gov/edu/watercyclesummary.html It is also possible for snow and ice to sublimate directly into the atmosphere and then there is evapotranspiration, this is where water transpires form plants and also evaporates out of the soil. http://ga.water.usgs.gov/edu/watercyclesummary.html This water vapor rises into the atmosphere until it reaches cooler regions then it condenses into clouds ans moved around by the earths air currents. http://ga.water.usgs.gov/edu/watercyclesummary.html As the clouds travel about the earth the water particles combine until they are too heavy to remain in the clouds at which point they fall in the form of precipitation Which can take the form of rain or snow. Some of the snow will fall on areas that never thaw and will become a form of water storage that can last for thousands of years. The rest will fall either into the oceans or on land where it will be absorbed or channeled into rivers and streams and eventually return to the ocean.