Shuck and Jive

Thursday, December 18, 2008

Time in a Bottle

In this segment, Dr. Albert Bartlett uses an illustration from the Boulder, Colorado city council to show how steady growth leads to catastrophic outcomes.

When he was making this video (1999), city council members were discussing what would be an acceptable population growth rate.
One figure considered was 5% per year. 70/5% means that the population would double every 14 years. If that growth rate were to continue, Boulder, in one lifetime would be about the size of Los Angeles.

As he points out, you couldn't fit LA into the Boulder valley. Obviously, Boulder's growth will stop.
The only question is will we be able to stop it while there's still some open space or will we wait until it is wall to wall people and we're all choking to death?
He put up this interesting headline from the Denver Post:
Colorado has a three percent growth rate...that's like a third world country with no birth control.
Dr. Bartlett says:
We send foreign aid--family planning assistance--to countries that have smaller population growth rates than Colorado has.
Dr. Bartlett uses this example to show how short-sighted we are in regards to growth and how even city council members do not understand basic arithmetic. Then Dr. Bartlett talks about bacteria.
Imagine bacteria growing steadily in a bottle. They double in number every minute. At 11:00 a.m. there is one bacterium in the bottle. At 12:00 noon the bottle is full.
It has a doubling time of one minute. It is in a finite environment of one bottle. He asks three questions:
1) What time was the bottle half full?

Answer: 11:59.

The bacteria double every minute. Second question:
2) If you were an average bacterium in the bottle at what time would first realize that you were running out of space?
Before he gives the answer he reminds us that this type of steady growth is the centerpiece of the entire global economy.

To answer question two, he provides this table:

Table II. The last minutes in the bottle.
11:54 a.m. 1/64 full (1.5%) 63/64 empty
11:55 a.m. 1/32 full (3%) 31/32 empty
11:56 a.m. 1/16 full (6%) 15/16 empty
11:57 a.m. 1/8 full (12%) 7/8 empty
11:58 a.m. 1/4 full (25%) 3/4 empty
11:59 a.m. 1/2 full (50%) 1/2 empty
12:00 noon full (100%) 0% empty

He returns to the Boulder argument. Someone wrote a letter saying that growth in Boulder is not a problem because there is 15 times the amount of space that Boulder has already used.

So what time is it in Boulder?
The answer? Four minutes before 12, when the bottle is 1/16 full.
Suppose that at 11:58 some of the bacteria realize they are running out of space. So they launch a great search for new bottles. They search offshore on the outer continental shelf, in the overthrust belt and in the arctic, and they find three new bottles.
This is an amazing find. They have four times as many bottles. Surely, this will give them a sustainable society, says Bartlett. Right? Question 3:
3) How long can the growth continue as a result of the discovery of three new bottles; this quadrupling of the proven resource?
At 11:59 the bottle is half-full.
At 12:00 the bottle is full.
At 12:01 two bottles are full.
At 12:02 all four bottles are full.
Game over. Dr. Bartlett tells us that we don't need any more arithmetic than that to address what we hear from the experts that we can go on growing and increasing our consumption of fossil fuels because we will discover new resources to meet the requirements.

Turning to energy, Bartlett quotes former energy secretary, James Schlesinger:
In the energy crisis, "we have a classic case of exponential growth against a finite resource." (Time Magazine, April 25, 1977).
How much oil is there? When do we use it? In the 1960s and 1970s the consumption was 7 percent per year. Doubling time = 10 years.

This percent growth did not continue because OPEC raised its prices. But say it did continue. How long would 7% consumption last?

In 1973 we consumed 20.4 billion barrels of oil. 334 billion barrels since oil was discovered approximately 100 years before that, leaving us with 1765 billion barrels. That is data. The rest is projection of 7% per year.


Barrels Produced

Cumulative Use

Amount Left











1078 (half gone)






Had we continued at 7%, in 1981 we would have had three times as much left in reserve than we would have used in all of history. A lot of oil. From our bacteria in a bottle example, what time is it when you have three times as much reserve compared to what was used? Two minutes before twelve.

Doubling usage every ten years (7% increase in production per year) would have depleted the oil in two decades.

The segment concludes at this point. We will pick this up
next time.

Questions for discussion:

1) Where are we now in real numbers of barrels of oil?

2) What is our percentage rate of growth?

3) What time is it?

1 comment:

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