Wednesday, May 16, 2012
A BLESSING IN DISGUISE?
The Guarani Aquifer, located beneath the surface of Argentina, Brazil, Paraguay, and Uruguay, is one of the world's largest aquifer systems and is an important source of fresh water. Named after the Guarani indigenous people, it covers 1,200,000 km², with a volume of about 40,000 km³, a thickness of between 50 m and 800 m and a maximum depth of about 1,800 m. It is estimated to contain about 37,000 km³ of water (arguably the largest single body of groundwater in the world, although the overall volume of the constituent parts of the Great Artesian Basin is much larger), with a total recharge rate of about 166 km³/year from precipitation. It is said that this vast underground reservoir could supply fresh drinking water to the world for 200 years. However, at closer inspection, if the world population were to stay at an equilibrium of about 6.96 billions, not even taking into account that babies need less water than grown adults, this figure reaches 1600 years, allowing about 9 liters per day per person. Due to an expected shortage of fresh water on a global scale, which environmentalists suggest will become critical in under 20 years, this important natural resource is rapidly becoming politicized, and the control of the resource becomes ever more controversial.