
Humans Are Draining Even More of Earth's Freshwater Than We Thought - DrScump
http://www.smithsonianmag.com/science-nature/humans-are-draining-even-more-earths-freshwater-we-thought-180957444?no-ist
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CapitalistCartr
We have two problems, neither of which is a lack of water. We use water but we
don't use it _up_. Our first problem is lack of cheap energy. Energy purifies
water, moves it to where its needed. Our second is a lack of politicians with
backbone, which is our own fault.

Where I live, my city pols subsidized water, people used more, said pols cried
about water shortages and passed restrictions, while we are awash in fresh
water. The city across the bay restricted waste early, implemented recycling,
now has one of the biggest waste-water recycling systems in the USA, raised
the price of city water while providing financial aid to the poor, and
finally, showed ruthless backbone in locking in water rights elsewhere,
including stealthy purchases using strawmen.

~~~
crusso
The article is really about the effect of evapotranspiration. It's more of a
look into a hidden effect of our attempts to remove and control larger amounts
of fresh water. It isn't really a discussion of general policy.

~~~
abandonliberty
I was curious how much of the evaporation we'd get back as freshwater. About
20% assuming its evenly spread over the world.

1.1 x 10^14 cu m of water falls on land per year. [0]

5 x 10^14 cu m falls yearly on the earth [1]

80,000 cubic meters is said to be lost to this effect [2].

[0][http://voices.nationalgeographic.com/2012/03/14/are-we-
runni...](http://voices.nationalgeographic.com/2012/03/14/are-we-running-out-
of-water/)
[1][http://hypertextbook.com/facts/2008/VernonWu.shtml](http://hypertextbook.com/facts/2008/VernonWu.shtml)
[2][http://www.jordantimes.com/news/local/80000-cubic-metres-
wat...](http://www.jordantimes.com/news/local/80000-cubic-metres-water-dams-
lost-evaporation-during-hot-spell%E2%80%99)

~~~
schiffern
I have to wonder if this result is due to increased evaporation (from the dam
surface) or increased transpiration (from non-irrigated and irrigated fields).
With oxygen isotope analysis the two can be distinguished.

This type of analysis reveals that trees are responsible for about 80% of all
terrestrial rainfall.[1] In contrast to man-made desalination facilities, this
water falls freely as rain instead of being owned and controlled.

Global deforestation/desertification is perversely convenient for those
interests vying to control water, since in a very real way it eliminates the
competition.

[1]
[http://www.nature.com/nature/journal/v496/n7445/abs/nature11...](http://www.nature.com/nature/journal/v496/n7445/abs/nature11983.html)

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contingencies
For another ancient irrigation project, still intact, see
[https://en.wikipedia.org/wiki/Dujiangyan](https://en.wikipedia.org/wiki/Dujiangyan)

