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Re: Responsible comments wanted on DRAFT essay
Mark wrote:
-> The importance of irrigated agriculture can not be overstated. 1/3
of the
-> world’s food production comes from 4% of the world’s land. This is
only
-> possible because of highly productive irrigated agriculture. To
replace
-> this production it would be necessary to farm 36 additional Iowas.
There
-> are not 36 additional Iowas on the planet. Those who criticize
irrigated
-> agriculture should also take responsibility and point to those who
would
-> not be fed without irrigated agriculture.
This is true. Nevertheless, modern agriculture can not be sustained.
Here is the final essay:
================================================================
THERMODYNAMICS AND THE SUSTAINABILITY OF FOOD PRODUCTION
by Jay Hanson <jhanson@ilhawaii.net> — revised 11/03/96
All matter and energy in the universe are subject to the Laws of
Thermodynamics. In the discipline of Ecological Economics,
systems are delimited so that they are meaningful to our economy.
What does thermodynamics have to do with the sustainability of
food production?
The two essential forms of stored thermodynamic potential are
"energy" (e.g., a barrel of oil) and "order" (e.g., clean
drinking water and deep topsoil). "Entropy" is a measure of the
unavailability of energy: the entropy of oil increases as it
burns, and the entropy of a water table increases as it falls
because more energy will be required to pump it to the surface.
Entropy can also be thought of as a measure of disorder in a
system: polluted water that requires purification has higher
entropy than the same water unpolluted, and the entropy of
topsoil increases when it is dispersed or polluted by salt from
evaporating irrigation water.[1]
Modern agriculture is increasing entropy in both its sources
(e.g., energy, soil, and ground water) and its sinks (e.g., water
and soil). Thus, modern agriculture is not circular -- it can not
be sustained.
Consider the most important limiting variable -- energy.[2]
There is NO substitute for energy. Although the economy treats
energy just like any other resource, it is NOT like any other
resource. Energy is the precondition for ALL other resources
and oil is the most important form of energy we use, making up
about 38 percent of the world energy supply.
40 years ago, geologist M. King Hubbert developed a method for
projecting future oil production and predicted that oil
production in the lower-48 states would peak about 1970. These
predictions have proved to be remarkably accurate. Both total
and peak yields have risen slightly compared to Hubbert's
original estimate, but the timing of the peak and the general
downward trend of production were correct.[3]
In March of this year, World Resources Institute published a
report that stated:
"Two important conclusions emerge from this discussion. First,
if growth in world demand continues at a modest 2 percent per
year, production could begin declining as soon as the year 2000.
Second, even enormous (and unlikely) increases in [estimated
ultimately recoverable] oil buy the world little more than
another decade (from 2007 to 2018). In short, unless growth
in world oil demand is sharply lower than generally projected,
world oil production will probably begin its long-term decline
soon -- and certainly within the next two decades."[4]
Well, so much for oil! Should we be alarmed? YES! Modern
agriculture -- indeed, all of modern civilization -- requires
massive, uninterrupted flows of oil-based energy.
To really understand the underlying causes and implications
of oil depletion, one must stop thinking of the "dollar cost"
of oil, and take a look at the "energy cost" of oil. We note
that the energy cost of domestic oil has risen dramatically
since 1975.[5] As oil becomes harder and harder to find and
get out of the ground, more and more energy is required to
recover each barrel. In other words, the increasing energy
cost of energy is due to increasing entropy (disorder) in our
biosphere.
Optimists tend to assume that the "type" of energy we use is
not significant (e.g., liquid vs. solid), that an infinite
amount of social capital is available to search for and produce
energy, and that an infinite amount of solar energy is
available for human use. Realists know that none of these
assumptions is true.
In fact, all alternative methods of energy production require
oil-based energy inputs and are subject to the same inevitable
increases in entropy. Thus, there is NO solution to the energy
(entropy or disorder) problem, and the worldwide energy-food
crisis is inevitable.
When we can no longer subsidize modern agriculture with massive
fossil energy inputs (oil-based pesticides and fertilizers,
machine fuel, packaging, distribution, etc.), yields will drop
to what they were before the Green Revolution![6] Moreover,
billions of people could die this coming century when the U.S.
is no longer able to export food[7] and mass starvation sweeps
the Earth.
Is there nothing we can do?
We could lessen human suffering if all the people of Earth
cooperated for the common good. But as long as political
systems serve only as corporate errand boys, we're dead.
==============================================================
1. p.p. 42-43,
ENERGY AND THE ECOLOGICAL ECONOMICS OF SUSTAINABILITY,
John Peet; Island Press, 1992. ISBN 1-55963-160-0.
Phone: 800-828-1302 or 707-983-6432; FAX: 707-983-6164
http://www.islandpress.com
2. http://www.igc.apc.org/millennium/g2000r/fig13.html
3. p. 55, BEYOND OIL, Gever et al.; Univ. Press Colorado, 1991.
303-530-5337 See also:
http://www.wri.org/wri/energy/jm_oil/gifs/oil_f4-5.html
4. http://www.wri.org/wri/energy/jm_oil/index.html
5. http://csf.Colorado.EDU/authors/hanson/page20.htm
6. p. 27, Gever et al., 1991.
7. Estimated in 1994 to be about 2025 by Pimentel. See:
http://csf.Colorado.EDU/authors/hanson/page40.htm
This article arrchived at:
http://csf.Colorado.EDU/authors/hanson/page65.htm
References: