From: Glenn Morton (glennmorton@entouch.net)
Date: Tue Nov 11 2003 - 06:18:42 EST
Kenneth Piers wrote:
> Unfortunately, we can not eat oil directly - most humans
>prefer normal food materials for sustenance.
>
Peter brunt replied:
>Ken, this is an interesting point. Can you back this up with facts and
>figures? People have talked for decades of returning prodction to the
>Sahara using purified seawater to growing plants.
I can:
“A city of 100,000 people using the biomass from a sustainable forest (3
tons/ha) for fuel would require approximately 220,000 ha of forest area,
based on an electrical demand of 1 billion kWh (860 x 109 kcal=1 kWh) per
year. Nearly 70% of the heat energy produced from burning biomass is lost in
the conversion into electricity, similar to losses experienced in coal-fired
plants.” David Pimentel et al, “Renewable Energy: Economic and Environmental
Issues,” BioScience 44(1994):8:536-547, p. 537
Note that this is 2.2 hectares per person. There are 915,800,000 hectares
total in the US lower 48 (less than 1% of Alaska is agricultural so I will
leave it out), 390,311,617 in agriculture in 1987 the last Agricultural
Census (see
http://www.fao.org/WAICENT/FAOINFO/ECONOMIC/ESS/census/wcares/2usatb.asp)
There are, according to the July 2003 estimate of the CIA World Fact book,
290,342,554 people in the US. At 2.2 acres per person you need 638,753,619
hectares, or just shy of twice what we have under agriculture today. To see
a map of where the agriculture is today see:
http://www.nass.usda.gov/census/census92/atlas92/html/m079.htm
You will see that there is really only a small part of the US which is
mostly agricultural. Finally consider this:
'The Earth has about 11 billion hectares (28 billion acres) of productive
land and sea space, after all unproductive areas of ice caps, desert and
open ocean are discounted. divided between the global population of 6
billion people, this total equates to just 1.9 hectares per person. Yet the
WWF report shows that the ecological footprint of the world average consumer
in 1999 was 2.3 hectares per person, or 20 percent above Earth's biological
capacity of 1.9 hectares per person.
"People in different countries have vastly different ecological footprints.
That of the average African or Asian consumer was less than 1.4 hectares per
person in 1999, the average Western European's footprint was about five
hectares, and the average North American's was about 9.6 hectares." Claude
Martin, "Ecological Footprints: The March Toward Destruction of the
Environment," International Herald Tribune July 24, 2002, p. 7
>
>As far as declining water is concerned, there is little cause for optimism
>here either, especially if that optimism is based on the fact that the
>oceans contain a lot of water. Once again, to render ocean water potable
>requires very substantial energy inputs.
>
>Maybe I am an optomist and Ken maybe the pesimist, but it has been
>visualised that sea side nuclear plants could be devoted to this solution.
>
>>If those energy inputs are primarily fossil fuel inputs and if oil
>production goes into decline, producing fresh water from sea water becomes
>an even more questionable project than it already is.
>
>Sorry to sound so evangelical, but I believe there are answers to
>the crises
>foreseen.
>
>respectfully,
>Peter Brunt
>
>
>>>> "Peter Brunt" <pbrunt@xtra.co.nz> 11/10/2003 12:57:44 AM >>>
>
>Darryl
>
>Declinign water and oil sure are relevant issues.
>
>But I can't help returning to Calvin - of photosynthesis fame - who wrote
>for Scientific American shortly after the first oil shock. His
>view was that
>once oil reserve exploration costs crossed over the line of growing plants
>for oil then it would be economically feasible to lay aside vast areas of
>land for that purpose. He may well have been rubbished since, but I am
>unaware of any negative comments regarding this idea. If I remember
>correctly he even identified a particular _Euphorbia_ species as a suitable
>plant for the role. Such plants are able to grow well in fairly arid
>climates so currently unsuitable land could be brought into production.
>
>Do you, Glen or any else know if further research has been condusted on
>Calvin's ideas?
>
>As to water shortages. There are tonnes in the oceans and surely as the
>need to produce water of irrigation quality matches the costs of
>desalination plantrs then the matter will be done. Sure the
>problem will be
>shifting the water to the right place. But that too will be a matter of
>econics, won't it!!?
>
>Perhaps I am too optomistic!
>I would like to hear your and others repsonse.
>
>Peter Brunt
>
>
>
>While we have discussed the relationship between declining oil supplies and
>its relationship to us as Christians, I don't think we have discussed the
>parallel problem of declining water supplies.
>
>http://www-geology.ucdavis.edu/~GEL115/115CH18miningwater.html is chapter
>15 of a set of lecture notes by Dr. Richard Cowen of the Univercity of
>California at Davis. The course is (and the notes) are on the
>relationships
>between natural resources and history. Very good reading for those who are
>not familiar with those relationships.
>
>Perhaps some of you would like to discuss this topic. Living as I
>do in the
>middle of the Texas High Plains which is facing this very problem, but not
>being a farmer, or a rancher, or a business owner in the area, I don't have
>much to say except life is going to get tough, some will loose their jobs,
>some their companies, but hopefully we are past the shooting stage of the
>1800's range wars.
>
>A few weeks ago I was with two other geologists and as we drove by miles of
>land that was once irrigated but is now being dryland farmed or grazed, one
>of them made the analogy that we were driving over a depleated resevoir
>except that instead of being an old oil field (all three of us started in
>the oil business but only one still is and he is, by his on statement
>"semi-retired" at 53) it is an old water field. Some of you may recognize
>the name - the Ogallala. It isn't depleated everywhere but those folks had
>given up trying to irrigate from it and slowly the big ranches are being
>sold off. I don't know more than a half dozen people that own land around
>here but last year a 6000 acre ranch was sold, then one partner of a 4000
>acre ranch sold his half, and now a third place is for sale. I don't know
>its size but I would guess around 10,000 acres more or less. I sure can't
>blame the farmers for selling their water rights given the fluctuation in
>commodity prices and the vagaries of crop yield but it is raising the
>temperature of some people's tempers and I think it won't be long before it
>starts stressing the control on their behavior that their religion exerted
>over the past decades when times were good and there was a general
>consensus
>about what was and was not the right thing to do with the water under your
>land.
>
>Maybe reaching a consensus on the young earth/old earth argument isn't as
>important as praying that we figure out a way to stay civil with our
>neighbors. This problem is already spreading and unless the
>climate changes
>a lot for the wetter I think it will continue to spread and cause economic
>hardships across the country.
>
>Darryl
>
>
>
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