Thursday, October 23, 2014

How Much Water Do We Have?

by Antonio C. Antonio
October 16, 2014

The main difference between Earth and the other planets is the presence of water.  Water represents life or the presence of life.  It is common knowledge and fact that life evolved in the aquatic habitat.  Humans are also generally made of water… 65% of the human body is water and man cannot exist without it.

Earth’s surface area is 510 million square kilometers.  149 million square kilometers is land while 361 square kilometers is water.  This translates to 70.8% of the Earth’s surface is water while 29.2% is land.  This simply means that a majority of the Earth’s surface is water and our planet is predominantly viewed as a liquid planet. 

This is great news, isn’t it?  Water, being a life-support element, perpetuates the existence of life forms on Earth.  But wait, and here’s the bad news… most of the water available to us is unfit for human consumption.  Although 70.8% of the Earth’s surface is water, only 3.5% of this is fresh water which is actually consumable… 96.5% is salt water and is unfit for human consumption.  Other sources of fresh water are water vapour which exists in the air, rivers and lakes, and icecaps and glaciers; which, however, are quite difficult to estimate.  All these point to an abundance of water supply for humanity.  But is 361 million square kilometers of water usable?... hardly not. 

The total water volume on Earth is calculated to be 326 million trillion gallons and the total fresh water available for human consumption is 11 million trillion gallons.  The daily requirement of an individual is 1 gallon; meaning, human consumption of fresh water is estimated at 7 billion gallons on the assumption that the total world population is 7 billion.  Other consumption like industrial, business, household and other related applications are not yet included in the total daily consumption of 7 billion gallons.

Water consumption for survival and life-support systems is understandable and acceptable.  But the worrisome consideration is the level of pollution that is continually being released into the fresh water supply.  I should mention that water acts as an effective medium of pollutants.  This definitely lessens the level of available fresh water which is directly proportionate to the volume of fresh water getting polluted every day.

A lot of people have attempted to estimate the volume of fresh water for human and other applicable use… but these largely remain to be “estimates”.  The biggest failure in these attempts is to estimate the volume of fresh water lost to pollution with the passage of time.  So, how much water do we have?

Just my little thoughts…

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