Water Dynamics/ What is Water?
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.
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.