Veg*n Cooking and Other Random Musings: The Limits of Growth: The 30-Year Update - A Review

Monday, December 22, 2008

The Limits of Growth: The 30-Year Update - A Review

The Limits to Growth was originally published in 1972 and has subsequently been updated twice at the 20- and 30-year marks of the original publication. Commissioned by the Club of Rome, the authors created a computer model, World3, to look at the relationships between exponential growth, human systems, environment, and finite resources. They do not try to make predictions about the future with the World3 model –variables such as the amount of available resources, the capacity of “sinks” to absorb pollution, or the maximum productive capacities of soil or technology can only be educated guesses – but rather, seek to explore possible trends when accounting for certain assumptions in the variables.

A little aside: the “scientist” in me was very pleased when reading this book. The authors make sure to clearly and consistently explain the limitations and assumptions in the model and its various scenarios. They remind us – as all good scientists should – that we should be skeptical, yet respectful; we should look at their ideas with honest, open eyes and minds, but also be willing to come to different conclusions about what we see, to disagree with their assumptions, because nobody really knows.

They approach the idea of limits from a systems perspective – focusing on the “big picture” – this does not mean that systems analysis does not look at individual elements, but it looks at individual elements in relation to other elements or how that element affects the whole. They do not seek to gain insight about any one variable in the model on its own.

A main focus, and thus part of the purpose of the model is to explore the limits of exponential growth in a finite world. The concept of exponential growth is very important, though not well understood. This isn’t because the concept is hard to grasp, there are many examples that clearly illustrate it, it is that the ramifications of understanding the situation are complex and face us with real limits that call for a fundamental change in the nature of our daily existence and interaction with our environment. An easy way to begin to look at exponential growth is this question, “Why does the population continue to expand rapidly in absolute numbers even as the birth rate is declining?” The short answer is the age distribution of the population and the sheer size of the population. Though couples are choosing to have fewer children, there are more couples coming of reproductive age, thus we end up with a net increase.

Perhaps now we can understand how the repercussions of something consequential like population, resource demand/availability, or pollution can be affected by exponential growth. This is why when someone says something like “we have a 150 year supply of ‘x’ resource left” it is very misleading. These figures are derived at the consumption rate at the time, the 150 year figure only applies if there is no growth in demand for the resource over time – this is something that is not likely to happen unless we reach very harsh limitations.

The World3 model used to chart the possible interactions of variables such as food/person, services/person, consumer goods/person, industrial output/person, population, resources, pollution, ecological footprint, life expectancy, and human welfare, is inherently limited in that it doesn’t (because it is too complex and speculative) account for war, political strife, corruption, or even all of the variables affecting those mentioned above. The point of the model is not to make predictions of the future, but to give a rough idea of what could lie ahead, what our possible future could look like, what problems we could be faced with, what the trends show, etc.

What I noticed immediately was that accounting for just one variable – even completely – was not enough. Simply reigning in population does nothing to stymie pollution or land degradation, just as simply reducing pollution does nothing to increase the abilities of a limited amount of land to feed an exponentially growing world. What you are left with are three basic scenarios, all involving overshoot as the authors believe our consumption is already above sustainable levels: oscillation, collapse, or equilibrium. Of course none of these scenarios are exclusive, even a situation of equilibrium might have periods of oscillation or scarcity due to delays, which will be discussed further below. There are also relative degrees of these scenarios, measures to account for these limits such as land stewardship, voluntary simplicity, pollution abatement, and family planning are taken and provide nuanced differences in results.

A scenario of oscillation basically means that the population would overshoot the planet’s carrying capacity (ability to provide all the services and goods the population needs) – but not to a point at which the planet could not recover - this would lead to periods of scarcity and die off leading to the reduction of the population below the carrying capacity of the environment. This could happen voluntarily, involuntarily, or in some combination. If crisis hit, we could understand that we’ve overshot of planets ability to sustain us and take whatever measures we can to come back in line with that ability, or we could allow Mother Nature to bring us back in line with that capacity via famine and possibly disease. Remember again, this model assumes no war or political strife, which is not likely to be the case in times so desperate. The scenarios of collapse, on the other hand, occur when no precautions or abatement measures are taken – or they are taken too late – and the planet loses its ability to completely recover. The scenarios often show a drastic reduction in available food, resources, and life expectancy, along with increasing pollution. A dramatic reduction in human population follows and the material standard of living can not be brought back up to previous standards - at least not on timescales useful to humans. The most desirable scenario, equilibrium, could involve times of over exceeding the carrying capacity, but the long-term trend is one in which the resources needed to sustain the population are above the demands of the said population. This could be brought about with sound social, industrial, and agricultural policy, pollution abatement, population reduction, but most importantly, with a voluntary reduction in desired material standard of living - this does not mean us all living like paupers, but I think the days of 3 TVs and 2 computers would be long gone at that point.

Part of the problem we face is the reality of delays and feedback loops. Pollution emitted from cars today do not immediately begin affecting the atmosphere – on the contrary – it will be many years before we feel the full affects of today’s pollution. Meaning, say this was a perfect world, and we ceased any and all pollution starting now, we would still see an overall increase in pollution for a few decades before it began to level off and decline. This is what muddies the picture of the future even further, how long does it take for the full affects to be felt? Nobody is completely sure because, of course, we are in uncharted territory. There are also feedback loops, both positive and negative to (try to) account for. A positive feedback loop is one where an effect on a variable in one direction causes it to move even faster or farther in that direction. Agriculture and population are the easy example of a positive feedback loop. More population can be sustained as humans move to agriculture, but as more people are born, more land has to be cultivated at an accelerated rate. A negative feedback look is where an effect on a variable in one direction causes a decreased response. An example of this could be the unsustainable extraction of water from a river. As more water is drawn out, less water flows to the sea, perhaps ceasing to flow all together.

These elements, the various choices humanity can make along the way, and all the variables that were not included in this model limit what one can glean about the future from a computer. But what it does show is the importance of looking at a system not just its constituent parts, of understanding the spiral effect of feedback loops and exponential growth, of understanding and accounting for delays where possible, of the importance of far sighted thinking and full accounting of the “costs” of the things that make our society possible, and that we understand that there is such a thing as too late to avoid collapse. We must find and respect limits, explore alternatives, and be ever-mindful of our ability to leave a world that is either better or worse than the one had, but only if we act - and act with foresight, humbly, and together.

This was an excellent book that I will be adding to J's Recommended Reads. I highly recommend it to anyone who wants to understand systems thinking, feedback loops, delays, or the many possible outcomes for our future.

I probably won't post again until next week due to the holidays. I made (and have planned) a couple of new recipes, but I am going to wait to post them until next week.

From the both of us here at Veg*n Cooking, we wish you a happy, safe, and non-consumerist holiday (like how I added that in?).

'Til next time!


Courtney said...

Thanks for the review--the book sounds really interesting!

I hope you have a happy, safe, and warm holiday! I know your plans had to change, but hopefully you will be less stressed not having to travel with the hug holiday crowds, and you can relax and enjoy a little down time! Enjoy!


jessy said...

oh wow - this book sounds really awesome, Jennifer! and something i would enjoy reading as well. i'm gonna see if we've got it at our library, for sure!

i really like that they remind us that we should be skeptical, yet respectful. that's a very good thing to remember. i like that they take into consideration many different scenarios. each one being different, kind of a warning to us all - and yet a bit hopeful in the same aspect. of course i fear the collapse & oscillation scenario, but both of them seem kind of real, too. we're over-using and abusing our world and eventually there's going to be some kind of break down. it's scary stuff! the equilibrium is the most desirable, indeed. i have to agree with you that a reduction has got to take place though - we don't need all this crap! reducing, reusing, and recycling has got to be the key! and i never would have thought about delays and feedback loops. that's some very interesting stuff. wow!

see you next week and i hope you both enjoy your holiday as well! be safe, keep warm, laugh a lot, and give lots of hugs!

Sophie said...

I love your blog! I just started one of my own:

I would love if you could add me to your blogroll or support me in some other way.

Thanks :)

Jennifer (of Veg*n Cooking) said...

Courtney - No problem. It really was interesting. It wasn't as hard of a read as you would figure something like that would be either.

I hope you have a wonderful holiday as well. We are really looking forward to a nice, long, warm weekend at home!

Jessy - You should really check it out if you can. I think in the end, what it really gives you is a different perspective as well as a reminder of the purpose and need for critical thinking.

I think it is important for people to keep an open mind to new ideas - which is why I will read/watch/listen to things that try to debunk theories that I believe in. It helps me understand the flaws in my own thought, learn something, and even hone in my argument. I also think it is important to be critical and skeptical - just because you really look up to someone does not mean they are infallible or immune to poor judgment or holes in logic.

I felt the same way when reading the book - the scenarios are scary yet real. It is very easy to see how we could go down the path of self-destruction, but it is also as easy to see how we could avoid the worst as well. Its all about how we choose to approach the situation and where we place our values.

Will do and you do the same. Have a wonderful holiday!

Sophie - Thank you. I will definitely check your blog out.

livinginalocalzone said...

This is something I just put on my request list at the library. It sounds like a great read, thank you for passing it on! Keeping an open mind, having the courage to explore the basis of one's beliefs, and thinking through things in a bit more detail while respecting others is something I think everyone can benefit from, no matter what area of life it is applied to. I can't wait to get to reading!

Happy and safe times to you in the coming week, be good to yourself :-)

Jennifer (of Veg*n Cooking) said...

Living in a Local Zone - I think you will enjoy this book - I'd love to hear what you think about it if you do end up reading it.

I couldn't agree more - I don't think any of us really can be firm about much of anything - it helps to keep that in mind when forming ones opinion. You can disagree with someone without being disrespectful, you can change your opinion without being a "flip-flopper", we just have to get comfortable with doing so. Having a degree in a field like psychology certainly helps, I remember the biggest thing I got out of learning about the history of psychology is that all the ideas that people were "certain" about back in the day, things that were taken as a given, as "fact", have now been discredited and seem so silly to us. We should keep in mind that we could be like that one day, the ideas we hold so firmly, things we think are so certain, could be cast away with new knowledge.

Back at you - take care of yourself and eat well!

Cookiemouse said...

Less is more.

Jennifer (of Veg*n Cooking) said...

Cookiemouse - For sure!