Canadian mennonite article series: #2: limits and ecology

Canadian mennonite article series: #2: limits and ecology - spending our children's world

“Are humans smarter than yeast?”
Bob Shaw and Richard Heinberg, Energy Experts

The previous article in this series established a notion of global limits, such that exceeding these limits could damage the world, and negatively affect life on the planet. In my next three articles I would like to examine three classes of limits:

1. Ecological limits

2. Energy limits

3. Food production and distribution limits

These three are inter-related, meaning that it is easy to dismiss these limits if they are considered in isolation:

1. In the absence of energy limits, many high-tech solutions to ecological problems can be imagined.

2. In the absence of ecological concerns, coal can provide for our energy needs for a long time.

3. In the absence of ecological and energy limits, we can dump enough nitrogen and fresh water around the world to grow nearly limitless amounts of food.

In this article I would like to focus on ecological limits. Specifically, I interpret being a steward of creation to mean living within these limits, limiting the net, overall impact that we have on God's world. I agree that creation has been given to us, such that it is appropriate to hunt and fish for food, but species extermination and fisheries collapse, both due to exceeding ecological limits, cannot possibly be part of God's plan. Similarly the burning of fossil fuels is not inherently problematic or immoral, it is the amount of burning which is the problem.

Although the natural world is resilient to damage and human impacts, there are limits to this resilience. Although not a complete list, some of the dominant worldwide ecological limits are:

1. The rate at which carbon-dioxide is removed from the atmosphere

2. The rate at which atmospheric pollutants are processed and neutralized

3. Fresh water flow in rivers and fresh water recharge in aquifers

4. The rate at which fish stocks grow

5. The minimum land area required for species and ecosystesom survival

6. The rate at which fertilizer run-off can be processed in rivers and lakes

7. Arable land

With the possible exception of limits on arable land, there is clear evidence of all of the other limits being encountered or exceeded

1. We are putting carbon dioxide into the atmosphere faster than it is removed, thus carbon-dioxide levels have been increasing for over a century. We're playing a huge scientific experiment with the atmosphere.

2. Industrial pollution has lead to acid rain, the acidification (and subsequent death) of lakes. Extensive coal burning has lead to widespread mercury pollution.

3. There are major rivers in which so much water is taken (mostly for irrigation) that the river only barely (or sometimes not at all) reaches the sea. Examples include the Yellow River in China and the catastrophe around the Aral Sea in western Asia. Similarly water-table levels are dropping due to excessive water draw for irrigation from ancient aquifers, notably the Ogallala Aquifer in the United States.

4. Although the oceans are extremely large, only certain portions are fertile, in terms of producing abundant life. That the oceans have limits, and that exceeding these limits leads to a long recovery time, has become abundantly clear from Canada's cod experience on the east coast.

5. Statistics on rainforest destruction have become so familiar that we almost shrug them off. The shrinking of habitat and the chopping of habitat into pieces by roads or fields slowly pushes species to extinction. Humans are pushing the limits of habitat encroachment and we are seeing the consequences: extinction rates 100 to 1000 times higher than normal.

6. Due to technological development and cheap energy humans have been able to produce fertilizer – fixing nitrogen and mining phosphates – at rates far, far greater than nature. The relatively indiscriminate use of such fertilizers runs off the fields and into waterways, where they induce extremely vigorous plant (algae) growth, deplete the oxygen, and lead to “dead zones” now found worldwide (Lake Erie, Gulf of Mexico, Baltic Sea).

Looking through the above list, there can be absolutely no dispute of anthropogenic (human) impact on the worldwide ecology. Let me remind you of the dangers with which humankind is playing: If the above limits are real, by exceeding them we damage the “system” (our planet), reducing the planet's ability to support life. Exceeding the above limits leads to global warming, forest death, drought/famine, fishery collapse, mass extinction/ecosystem collapse, and lake death, respectively. Wishing to continue status-quo is to deny any of the above limits.

In addition to the existence of ecological limits, it is crucially important to understand that most natural systems are nonlinear. That is, nature can withstand a modest amount of abuse with no ill effects, but as the abuse exceeds some limit (a so-called “tipping point”) sudden ecological collapse is possible. One of the most important (and dreadful) examples comes from global warming:

As the planet warms, arctic ice melts. When the ice, which used to reflect much sunlight, is gone the arctic warms further, thawing the permafrost (tipping point). As the permafrost thaws and decomposes it releases huge amounts of methane. The methane, a far more potent greenhouse gas than carbon dioxide, greatly accelerates global warming. At this point, even a complete cut in human CO₂ emissions would be futile – the damage has been done.

There are three lessons to be learned about nonlinear systems from such an example:

First, that modestly reducing human impact before a limit has been reached is far more effective than draconian measures afterwards.

Secondly, that it is dangerously ignorant to suppose that “a little global warming might be good for Canada,” a perspective that wishes for slightly warmer temperatures, but with other weather patterns left unchanged. A nonlinear climate is not offering such an arrangement: if we humans want to play with temperature, then we are also playing with wind, precipitation, seasonal patterns etc.

Finally, that it is ecological nonlinearities which make perceiving, anticipating, and finding political motivation to address limits so difficult: until an ecological limit is neared, it is only a small handful of scientists or nonlinear systems theorists who see a problem, whereas most people (and politicians) see no need to react. It is therefore telling that “climate change” and “global warming” are topics of some controversy or skepticism among politicians and the popular press, a controversy and uncertainty easily exploited by governments to do nothing, while an overwhelming number of climate scientists are terribly worried.

By running into and ignoring global limits we are playing “God” with creation, an act of terrible arrogance. God's gift to us did not end with a world to subdue; a second gift was a mind with which to contemplate our actions and to anticipate their effect. God gave us the insight and intellect to understand our world, and charged us with the responsibility of maintaining it. Yeast is not smart enough to recognize the limits of the bowl in which it is growing, are we?