Wednesday, September 29, 2010

[Geology2] Worldwide groundwater depletion rate accelerating

Uh-oh . . .

> Worldwide groundwater depletion rate accelerating
> Published 27 September 2010
> In recent decades, the rate at which humans worldwide are pumping dry
> vast underground stores of water that billions depend on has more than
> doubled; if water was siphoned from the Great Lakes as rapidly as
water is
> pumped out of underground reservoirs, the Great Lakes would go
bone-dry in
> around 80 years.
> In recent decades, the rate at which humans worldwide are pumping dry
> vast underground stores of water that billions depend on has more than
> doubled, say
> who have conducted an unusual, global assessment of groundwater use.
> These fast-shrinking subterranean reservoirs are essential to daily
life and
> agriculture in many regions, while also sustaining streams, wetlands,
> ecosystems and resisting land subsidence and salt water intrusion into
fresh water supplies.
> Today, people are drawing so much water from below that they are
> enough of it to the oceans (mainly by evaporation, then precipitation)
> account for about 25 percent of the annual sea level rise across the
> the researchers find.
> Soaring global groundwater depletion bodes a potential disaster for an
> increasingly globalized agricultural system, says Marc Bierkens of
> University in Utrecht, the Netherlands, and leader of the new study.
> "If you let the population grow by extending the irrigated areas using
> groundwater that is not being recharged, then you will run into a wall
at a
> certain point in time, and you will have hunger and social unrest to
go with
> it," Bierkens warns. "That is something that you can see coming for
> He and his colleagues will publish their new findings in an upcoming
> of Geophysical Research Letters, a journal of the American Geophysical
Union (AGU) (the paper, "A worldwide view of groundwater depletion,"
may be
> downloaded at the AGU Web site <>).
> In the new study, which compares estimates of groundwater added by
rain and other sources to the amounts being removed for agriculture and
other uses,
> the team taps a database of global groundwater information including
maps of groundwater regions and water demand. The researchers also use
models to estimate the rates at which groundwater is both added to
aquifers and
> withdrawn. For instance, to determine groundwater recharging rates,
> simulate a groundwater layer beneath two soil layers, exposed at the
top to
> rainfall, evaporation, and other effects, and use forty-four years
worth of
> precipitation, temperature, and evaporation data (1958â€"2001) to
> the model.
> Applying these techniques worldwide to regions ranging from arid areas
> those with the wetness of grasslands, the team finds that the rate at
> global groundwater stocks are shrinking has more than doubled between
> and 2000, increasing the amount lost from 126 to 283 cubic kilometers
(30 to
> 68 cubic miles) of water per year. Because the total amount of
> in the world is unknown, it is hard to say how fast the global supply
> vanish at this rate. If water was siphoned as rapidly from the Great
> however, they would go bone-dry in around eighty years.
> Groundwater represents about 30 percent of the available fresh water
on the
> planet, with surface water accounting for only one percent. The rest
of the
> potable, agriculture friendly supply is locked up in glaciers or the
> ice caps. This means that any reduction in the availability of
> supplies could have profound effects for a growing human population.
> The new assessment shows the highest rates of depletion in some of the
> world's major agricultural centers, including northwest India,
> China, northeast Pakistan, California's central valley, and the
> United States.
> "The rate of depletion increased almost linearly from the 1960s to the
> 1990s," says Bierkens. "But then you see a sharp increase which is
> to the increase of upcoming economies and population numbers; mainly
> India and China."
> As groundwater is increasingly withdrawn, the remaining water "will
> eventually be at a level so low that a regular farmer with his
> cannot reach it anymore," says Bierkens. He adds that some nations
will be able to use expensive technologies to get fresh water for food
> through alternative means like desalinization plants or artificial
> groundwater recharge, but many won't.
> Most water extracted from underground stocks ends up in the ocean, the
> researchers note. The team estimates the contribution of groundwater
> depletion to sea level rise to be 0.8 millimeters per year, which is
about a
> quarter of the current total rate of sea level rise of 3.1 millimeters
per year.
> This is about as much sea-level rise as caused by the melting of
> and icecaps outside of Greenland and Antarctica, and it exceeds or
> into the high end of previous estimates of groundwater depletion's
> contribution to sea level rise, the researchers add.
comment -
Earth, like civil society, is grinding to a halt.
Our aquifers are depleting yes, but worse, we have depleted their

That pressure is part of a huge hydraulic system that keeps the
mechanics of
the earth in locomotion and in proper relationships. This is needed in
order to,
among other things, replenish and keep clean the ground water supplies.
"Science" hasn't figured this out yet.

We are closer to Dead Earth than we realize. But then, it will
reset by global upheaval and violent corrections to the geophysical
Like rewinding a clock. Most humans will not make it through the
Try to get some land on which to grow something. Though ultimately,
water wells will only be had in secret. Moreover, China, or a UN
consortium of
thug, mob-rule nations, would have no problem matching into our country
commandeering our water and resources, once past our meager land/sea
of our borders.

I believe we are going to see, in my lifetime - I am 57 - devastation,
suffering, and despair unparalleled since the Plague, if not in all
human history. Only "stewardship" of our environment will save our
systems. Those who see the natural world as the source of . . .


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