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BEFORE FOSSIL FUELS, EARTH'S MINERALS KEPT CO2 IN CHECK
Posted on Tuesday, April 29, 2008 @ 19:55:06 UTC by vlad
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Over millions of years carbon dioxide levels in the atmosphere have been moderated by a finely-tuned natural feedback system— a system that human emissions have recently overwhelmed. A joint University of Hawaii / Carnegie Institution study published in the advance online edition of Nature Geoscience links the pre-human stability to connections between carbon dioxide in the atmosphere and the breakdown of minerals in the Earth’s crust. While the process occurs far too slowly to have halted the historical buildup of carbon dioxide from human sources, the finding gives scientists new insights into the complexities of the carbon cycle.
Ken Caldeira of the Carnegie Institution’s
Department of Global Ecology and Richard Zeebe of the University of
Hawaii studied levels of carbon dioxide in the atmosphere over the past
610,000 years using data from gas bubbles trapped in Antarctic ice
cores. They used these records, plus geochemical data from ocean
sediments, to model how carbon dioxide released into the atmosphere by
volcanoes and other natural sources is ultimately recycled via
carbon-bearing minerals back into the crust.
When carbon dioxide levels in the atmosphere rise, the chemical
reactions that break down silicate minerals in soils are accelerated.
Among the products of these reactions are calcium ions, which dissolve
in water and are washed to the ocean by rivers. Marine organisms such
as mollusks combine the calcium ions with dissolved carbon dioxide to
make their shells (calcium carbonate), which removes both calcium and
carbon dioxide from the ocean, restoring the balance.
The researchers found that over hundreds of thousands of years the
equilibrium between carbon dioxide input and removal was never more
than one to two percent out of balance, a strong indication of a
natural feedback system. This natural feedback acts as a thermostat
which is critical for the long-term stability of climate. During
Earth's history it has probably helped to prevent runaway greenhouse
and icehouse conditions over time scales of millions to billions of
years — a prerequisite for sustaining liquid water on Earth's surface.
“The system is finely in tune,” says Caldeira.
“That one or two percent imbalance works out to an average imbalance in
natural carbon dioxide emissions that is thousands of times smaller
than our current emissions from industry and the destruction of
forests.”
Previous researchers had suggested that such a system existed, but
Caldeira and Zeebe’s study provides the first observational evidence
supporting the theory, and confirms its role in stabilizing the carbon
cycle. But because it operates over such a long time scale—the time
scale over which landscapes are eroded and washed to the sea—this
geological feedback system offers little comfort with respect to the
current climate crisis.
Carbon dioxide is added naturally to the atmosphere and oceans from
volcanoes and hydrothermal vents at a rate of about 0.1 billion tons of
carbon each year. Human industrial activity and destruction of forests
is adding carbon about 100 times faster, approximately 10 billion tons
of carbon each year.
“The imbalance in the carbon cycle that we are creating with our
emissions is huge compared to the kinds of imbalances seen over the
time of the glacial ice core records,” says Caldeira. “We are emitting
CO2 far too fast to expect mother nature to mop up our mess
anytime soon. Continued burning of coal, oil and gas will result in
long-term changes to our climate and to ocean chemistry, lasting many
thousands of years.”
Source: Carnegie Institution
Via: http://www.physorg.com/news128684748.html
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SCIENTISTS AIM TO BOOST WORLD ENERGY SUPPLIES -- WITH MICROBES (Score: 1)
by vlad on Tuesday, April 29, 2008 @ 20:05:17 UTC
(User Info | Send a Message) http://www.zpenergy.com | British and Canadian scientists expect to begin trials next month (May) to find out whether microbes can unlock the vast amount of energy trapped in the world's unrecoverable heavy oil deposits. An estimated six trillion barrels of oil remain underground because the oil has become either solid or too thick to be brought to the surface at economic cost by conventional means.
Full story at http://www.physorg.com/news128692150.html [www.physorg.com]
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Gasoline to cost $10 a gallon in US soon? (Score: 1)
by vlad on Tuesday, April 29, 2008 @ 20:18:26 UTC
(User Info | Send a Message) http://www.zpenergy.com | | From KeelyNet News [www.keelynet.com]: Translating this price into dollars and cents at the gas pump, one of
our forecasters, the chairman of Houston-based Dune Energy, Alan
Gaines, sees gas rising to $7-$8 a gallon. The other, a commodities
tracker at Weiss Research in Jupiter, Fla., Sean Brodrick, projects a
range of $8 to $10 a gallon. While $7-$10 a gallon would be
ground-breaking in America, these prices would not be trendsetting
internationally. For example, European drivers are already shelling out
$9 a gallon (which includes a $2-a-gallon tax). Early last year, with a
barrel of oil trading in the low $50s and gasoline nationally selling
in a range of $2.30 to $2.50 a gallon, Mr. Gaines — in an impressive
display of crystal ball gazing — accurately predicted oil was
$100-bound and that gasoline would follow suit by reaching $4 a gallon.
His latest prediction of $200 oil is open to question, since it would
undoubtedly create considerable global economic distress. Further, just
about every energy expert I talk to cautions me to expect a sizable
pullback in oil prices, maybe to between $50 and $70 a barrel,
especially if there's a global economic slowdown. While Mr. Gaines
thinks there could be a temporary decline in the oil price, he's
convinced an overall uptrend is unstoppable. In fact, he thinks his
$200 forecast could be conservative, and that perhaps $250 could be
reached. His reasoning: a combination of shrinking supply and
increasing demand, especially from China, India, and America. - Source [www.boingboing.net] |
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Re: BEFORE FOSSIL FUELS, EARTH'S MINERALS KEPT CO2 IN CHECK (Score: 1)
by malc on Wednesday, April 30, 2008 @ 00:43:51 UTC
(User Info | Send a Message) http://web.ukonline.co.uk/mripley | The point is though that we need to stop burning fossil fuels irrespective of its price. My personal belief is that we are nearing the top of the tipping point after which the earths feedback systems switch to a new stable state. One which accommodates a higher level of CO2. Unfortunately this means much higher sea levels, totally different weather patterns and different ocean currents. The net effect being a complete change in where things grow and what can be grown. Since we "very clever" humans have as usual concentrated all our efforts in fighting against nature with monocultural growing patterns our foodstocks will collapse.
Oil is not going to be the problem it will be food.......you may have noticed it has already started. We'll spend the next few years pulling back on bio fuels, living with higher oil prices, higher food prices making us waste less and finally eating perfectly edible but imperfectly shaped and coloured food. After that there will be no more room to manouver and shortages will hit hard.
Yes folks, western consumers do not buy a carrot unless it is a certain shade of orange and shaped like a "carrot". The rest is ploughed back into the ground because nobody will buy it....utter madness. Ever noticed how that pack of 4 apples in the plastic tray are all identical in shape and colour!! come on!! nature is good but not that good! |
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