Tuesday, September 23, 2008

Avoiding Overshoot Means Weaning Ourselves Off Oil

In 1957 twenty-nine reindeer were introduced to St. Matthew Island, a small island in the Bering Sea that had never seen reindeer or caribou before. Six years later there were 6000 reindeer. But three years later, in 1966, there were only 42 reindeer left. What happened? 6000 reindeer were too many for such a small island. In the absence of natural predators they grew to a huge population and damaged the habitat so severely that they overshot the island's carrying capacity. Consequently the island was only able to support a small remnant of the reindeer.

The development of agriculture, thousands of years ago, enlarged the carrying capacity of land for humans. Saving and planting seeds meant that early farming societies were able to support larger populations than the hunting and gathering societies that predated agriculture. In his book, Overshoot, William Catton Jr. argues that when technology began to be powered by fossil fuels our relationship to Earth's carrying capacity changed dramatically for the worse.

By developing machines that liberate the energy locked up in fossil fuels we have supported a vastly expanded human population. Our global population is about 6 billion people and still growing. The problem is that instead of enlarging the Earth's carrying capacity, the use of fossil fuels has diminished it by giving us the ability to cut down forests, overfish the oceans, eliminate bio-diversity, and cause global warming, all at an accelerating rate. Thus, our global civilization has run out of unspoiled habitats to exploit. In the past, when civilizations ran out of room people migrated elsewhere. But now, there is no elsewhere. .

Catton draws an analogy between our dependence on fossil fuels, which originated from dead plants, hence the name "fossil fuels" with what he calls "detritus ecosystems". Detritus is the accumulation of dead organic matter. Bloom and crash cycles such as the algae blooms in lakes and seas depend upon exhaustible accumulations of dead organic matter for their sustenance. These algae blooms collapse and die off after all the seasonal detritus is used up.

"Detritus ecosystems flourish and collapse because they lack the life-sustaining biogeochemical circularity of other kinds of ecosystems." Our global industrial civilization is doing the same thing. By using up fossil fuels, a non-renewable source of energy we have managed to exponentially increase our population over a period of several hundred years. But our society is precariously dependent on dwindling non-renewable sources of energy to feed, clothe and house everyone. If we don't retool our economies soon, when we run out of oil the vast majority of people will starve to death.

Now that the price of oil has increased substantially, governments and oil companies are quickly moving into more unconventional sources, such as tar sands and shale deposits. Doing this will only accelerate environmental breakdown and global warming. It takes three times as much energy to extract and refine oil from the tar sands as it does to extract and refine crude oil. That means that the more we depend on the tar sands, the faster we use up accessible fossil fuels. The Alberta Tar Sands is already using enough natural gas to heat a quarter of Canada's homes. Not only that, but the process of extracting oil from tar sands is accelerating the growth in carbon dioxide emissions which is linked to global warming. The Alberta Tar Sands is now the largest industrial project on the planet, devouring millions of acres of boreal forest, creating huge man made toxic lakes and emitting almost a third of the total carbon dioxide emissions for all of Canada.

A carbon tax or a cap and trade system, eliminating subsidies to the oil and gas industries, and subsidizing public transit and renewable energy technology would preserve our market system and encourage a greener renewable economy.It would help make us more resilient in the face of peak oil.

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