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Its not to great of simplification to state that the failure to understand the concept of exponential growth by planners and/or legislators, is the single biggest problem in all of Environmental Studies and/or Management.
The Two Principle Problems with Energy Management:
Exponential growth drives resource usage for a very simple reason:
Human population increases exponentially:
At the moment there seems to be very little that can be done about this and hence, this represents our fundamental problem. That is, you can't really stop it:
This is directly
related to environmental problem solving as follows:
This should not be tolerated, by any one,
yet this makes the media circus go around.
"Math, formulas and other things that don't apply to real life"
(--anonymous comment from student evaluation of Physics 161 course
as the part they liked least about the course)
This again is a recipe for disaster as it means the public can be sold most anything
An example:
A survey of Boulder Colorado residents about the optimal size for growth returned a result that most residents thought that a growth in population at the rate of 10% per year was desirable.
Well 10% a year may not seem innocuous but let's see how these numbers would add up?
So in 7 years (year 2--7) the population has doubled and by then 10,000 new residents per year are moving to Boulder!
Clearly, Exponential growth, in general, is not understood by the lay public. If exponential use of a resource is not accounted for in planning - disaster can happen.
The difference between linear growth and exponential growth is astonishing.
In this example, one can clearly see that no matter what the growth rate is, exponential growth stars out being in a period of slow growth and then quickly changes over to rapid growth with a characteristic doubling time of
70/n years; n =% growth rate
Its important to recognize that even in the slow growth period, the use of the resource is exponential. If you fail to realize that, you will run out of the resource pretty fast:
Material | Rate | Exhaustion Timescale |
---|---|---|
Aluminum | 6.4% | 2007 -- 2023 | Coal | 4.1% | 2092 -- 2106 | Cooper | 4.6% | 2001 -- 2020 | Petroleum | 3.9% | 1997 -- 2017 | Silver | 2.7% | 1989 -- 1997 |
Exponential growth means that some quantity grows by a fixed percentage rate from one year to the next. A handy formula for calculating the doubling time for exponential growth is:
Doubling Time = 70/n years
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