Sunday, February 12, 2012

Water scarcity: reality or speech


Porto-Gonçalves in the problem analysis of the lack of water is really very interesting. In this first article we will concentrate only on one of the points that works how real is the concept of the "water scarcity".

Of all I recommend to read the full text of water does not deny to anyone, since it has no waste for whom we are concerned about such issues.






Porto-Gonçalves in the problem analysis of the lack of water is really very interesting. In this first article we will concentrate only on one of the points that works how real is the concept of the "water scarcity".

Of all I recommend to read the full text of water does not deny to anyone, since it has no waste for whom we are concerned about such issues.



Since the beginning the author tells us that there is a "speech of scarcity", and here, using the word "he remarks" marks clearly its position that this is a deliberate message and not a simple and innocent description of reality. And this founded it with figures who come to demonstrate that the situation is not as alarming as it seeks us to show.

As he tells Porto-Gonçalves, information circulating most commonly on the "stock" of drinking water as follows:

Planet Earth has 3/4 parts of water. Of this, 97% are the oceans and seas, which is why this water to salt, is not suitable for human consumption. Then is 3% of fresh water, but 2/3 of it are in solid state because they are ice and polar ice caps, ergo, are not available for human consumption at the end of the equation the result is that less than 1% of the total water on our planet would be safe.

This is the brief outline of the discourse from scarcity. And as brilliantly defines the author, it is "made" so that, in the end, the reader is already thirsty. There warns Porto-Gonçalves that we should not give by scientific any mere statistics because - as he says - there are a number of basic errors from the own scientific point of view in these numbers.

If these numbers are not entirely accurate, is because there are others factors were missing in the equation. And what we need to take into account is mainly that the fresh water on Earth is largely provided by the water cycle. And mostly as a result of evaporation from the oceans and seas.


Let's look at some data provides in this regard:

Approximately 505.000 Km3 evaporates each year of the oceans and seas (this is equivalent to a layer 1.4 metres thick on the surface of seas and oceans). Although these sources of water salt, salt is not transmitted in evaporation. Of these 505.000 Km3 80% returns to precipitate on the oceans and seas, but the remaining 20% drop over the continental surface. And the rains that fall on all continents, about 3/4 parts evaporate from lakes, ponds, rivers, soil and plants (evapotranspiration). It is 1/4 remaining drain to the sea again.


This cycle and these levels remain valid according to evidence from the last ice age. In other words, the amount of water available has not changed significant since at least 12,000 to 18,000 years ago.

Moreover, the amount of water available not only not declined but may even be increasing as a result of the melting of the polar ice caps and glaciers due to global warming. Although it sounds like a paradoja…

The question then seems to be that drinking water is not scarce at the global level. And however, according to UN reports nearly 3 billion people have no access to it. That leaves us thinking that the question to ask is not "does there is enough water for all?", but "who controls her?, and what uses it?".

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