Water Dynamics/ What is Water?

Drops of water
Drops of water
Water (from the Anglo-Saxon and Low German word, wæter) is the all-encompassing term used to describe the dynamic substance formed by small molecules that is without taste, color, or odor and is essential to all forms of life as we know them and continually discover more. Water is abundant on our planet and it exists in a myriad of places and forms: the bulk of it is in our oceans and polar ice caps, but water also takes the form of clouds and rainwater, icebergs and mountain glaciers, rivers, aquifers, and freshwater lakes. Water is perpetually transported from one body of water to another through its cycle of evaporation, precipitation, and runoff back to the sea. This process is called the water cycle and is crucial to the balance of all life on Earth.

Besides the water cycle there is also another force causing movement in water. Like the Earth, the Moon has gravity, and a bit of this gravity can be noticed on Earth, causing slight differences in the water levels of the oceans. This difference is called tidal movement and can be especially noted when you go to the beach.

Importance

Waves in the surf
The surf
All known forms of life require water to sustain them. Humans consume "drinking water" — water that has qualities compatible with the human body’s peculiar chemistry. Because water can contain many different substances, its taste and odor can vary depending upon its source. We like to drink the pure, fresh water of a mountain spring, but we carefully avoid the liquid contained in our putrid swamps and salty seas. The human body requires water that does not contain too much salt or other impurities. Water that is suitable for drinking is termed "potable” water. Apart from the drinking water that replenishes our thirst and hydrates our bodies, we also require water for agriculture, industrial manufacture, and transport.

Consequently, water plays a major role in the history of human civilization. Rivers, with the help of irrigation techniques, supply the water necessary for agricultural production. Rivers and the seas offer opportunities for travel and commerce. Within monumental time frames that span hundreds, thousands, and even millions of years, water runoff plays a key role in shaping our environment by eroding and transporting sediments: establishing river valleys and deltas. These rich soils and level grounds have fostered the establishment of large population centers and from them the rise of classical civilizations: such as the Egyptians in the Nile delta, the Babylonians at the Euphrates and Tigris rivers, and, of course, the Dutch in the Rhine and Meuse delta.

Did you know that:

  • the Celsius (°C) degree scale for temperature readings is based on water? 0°C (32°F) is the freezing point of water, while 100°C (212°F) is the boiling point of water, as measured at sea level.
  • the boiling point of water (and all other liquids) is directly related to barometric pressure? For example, on the top of Mt. Everest, water boils at about 68°C (154°F), compared to 100°C (212°F) at sea level. Conversely, water deep in the ocean near geothermal vents can reach temperatures of hundreds of degrees and still remain liquid.
  • that although water is often regarded as being colorless, it has a small intrinsic hue of light blue color ? It is difficult to perceive this in low quantities but this can be recognized, for instance, facing a great wall of glacial ice. [picture glacier]
  • that about 72% of the fat-free mass of the human body consists of water? To function properly, the body requires between one and seven liters of water per day to avoid dehydration — the precise amount depending on a number of factors including the environmental temperature and humidity, as well as the body’s level of physical and metabolic activity, among countless other factors. Water is lost from the body through excretion of urine, feces, sweat, and by exhalation of water vapor in breath.