There are 326 million cubic miles of endless blue sea occupying the expanse between our seven continents, making up 70% of the earth’s surface (Bureau of Reclamation, 2017).
With merely 5% of the ocean floor having been discovered and mapped, and with the deepest part reaching almost 7 miles, water seems to be as abundant as it is ominous.
Yet, it wouldn’t take much of the mineral-rich ocean to dehydrate a human being if consumed. The amount of sodium in seawater is much more concentrated than what the body can safely process, requiring more water as salt is consumed. Eventually, death would come as a result of dehydration without ever having the thirst quenched (Ocean Service).
Of the waters occupying 70% of the earth’s surface, only 3% is considered freshwater. And most of this freshwater reserve is inaccessible to humans — locked up in polar ice caps or stored too far underneath the earth’s surface to be extracted. Furthermore, much of the freshwater that is accessible has become highly polluted.
This leaves us with roughly 0.4% of the earth’s water which is usable and drinkable to be shared among the 7 billion of its inhabitants (World Atlas, 2018).
How Much Water is On Earth?
And still, much of this 0.4% is hard to get to. Most of it flows through underground aquifers which can be accessed by digging wells; the rest are found in rivers and streams which we refer to as, surface water. Much of the global population is hard-stricken having access to such a small percentage of freshwater on the earth’s surface (Perlman, 2016).
The United States Geological Survey provides a visual illustration (represented in spheres) as to the amount of available water in comparison to the size of the earth.
The largest sphere represents all of the water on earth (oceans, ice caps, lakes, rivers, groundwater) and has a volume of 332,500,000 cubic miles.
The second-largest sphere, with a volume of 2,551,100 cubic miles, represents the earth’s freshwater supply in liquid form. 99% of the liquid freshwater is groundwater, much of which is far too deep to be accessible.
The remainder of the earth’s freshwater exists in lakes and rivers, represented by the tiniest sphere, with a volume of 22,339 cubic miles (Perlman, 2016).
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The earth’s surface waters travel through a complex network of flowing rivers and streams. Rivers can obtain their water from two sources: base flow and runoff. Base flow is when the river collects its water from water-saturated areas in the ground, adding to its volume. Runoff is when the force of gravity naturally pulls water downhill from higher to lower altitudes. They usually start as small creeks in the mountains, and then gradually merge with larger streams as they flow downward, eventually forming large rivers which empty out into the ocean.
The Hydrologic Cycle
Water Conflicts Around the World
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• Violence erupts in 1992 over a dispute between Uzbekistan and Turkmenistan regarding the contested Tyuyamuyun reservoir. It continues to be a highly disputed water source in the region today (Factbook).
• In 2010, dozens of people were killed in Pakistan’s tribal region due to a water dispute which lasted over two weeks. According to a senior government official in the Kurram district which borders Afghanistan, the Mangal tribe stopped water irrigation on lands belonging to the Tori tribe. In total, 116 people were killed and 165 were injured (CNN, 2010).
• Four farmers were hacked to death in northeast Tanzania over the disputed Pangani River Basin in 2013 (Factbook).
• In 2016, 18 people were killed and 200 more were injured when the Indian Army clashed with economic protestors surrounding the highly-contested Munak canal, a water source that supplies New Dehli with three-fifths of its freshwater supply (Factbook).
• The drought-stricken conditions of major parts of Somalia often force herders to sell more of their livestock than they can afford to make a living with. This lack of economic stability fuels recruitment appeal with militant groups such as Al Shabaab, which provide cash incentives and other benefits to their soldiers. Other illicit activities such as pirating and livestock raiding are seen as reasonable alternatives to the declining stability of animal herding (Factbook).
Change is Needed
70% of the earth is covered in water, yet only 3% of it is fresh. Of that 3%, 2.6 of it is locked away in glaciers and polar ice caps. That leaves us with 0.4% of the earth’s water, in the form of rivers and underground aquifers, to try to utilize for our consumption and societal development. It is no wonder that in developing regions where clean water sources cross national boundaries, it often finds itself in conflict among those trying to secure a means to a healthy living.
With humans being made up of 60% water, our natural instinct might be to fight for it. But by collaborating to find ways to access the untapped groundwater beneath us, helping to conserve clean water use, and preventing further pollution of our clean water sources, it is possible for all peoples to have access to clean water.
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