Limits to Growth is a report originally published in 1972 which presented the results of a computer simulation of population and economy growing exponentially in a world of finite resources. The report caused significant debate and controversy but had a lasting impact.
Limits to Growth: The 30-Year Update is the second update since the original report. It contends that humanity is using critical resources and producing wastes at a rate that is not sustainable and that in the absence of sufficient intervention we potentially face a worldwide economic, societal and environmental collapse.
The authors examine these global issues through the lens of system dynamics, a methodology for analysing the behaviour of complex systems by modelling the interaction of their constituent elements. The findings of the report are derived from a computer model of worldwide population growth, industrial output, resource use, food production, pollution and other key factors.
The essential concepts:
- Population and economic production / industrial output are currently growing exponentially. This causes exponential growth in resource use and pollution.
- There exist ecological limits which, if exceeded, lead to long-term degradation of the finite resources and ecosystem services that humanity is dependent upon. (For example: the amount of oil that can be drawn before it becomes prohibitively expensive, the rate of harvest a population of fish will tolerate before collapse, and the amount of CO2 that can be emitted before causing catastrophic climate change.)
- Since:
a) Exponential growth in population & economic production causes us to accelerate toward these limits, and;
b) There are delays in our ability to gain feedback from and respond to these limits:
The global economic system is likely to cause a condition of overshoot, in which multiple ecological limits are unintentionally exceeded. - Relying solely on new technology and market forces is not sufficient to prevent overshoot. If the primary goal of society is continual growth, technology and markets will be harnessed to serve this goal, amplifying the tendency of the economic system to cause overshoot.
- Consequently, without intervention we will bring about an escalating series of crises in resource shortfalls and environmental degradation, leading to economic, ecological and societal collapse within the next 100 years.
Overshoot and collapse is the projected consequence of the ‘business-as-usual’ scenario, in which no substantial intervention is made to avoid collapse. In addition to this, the authors present several other scenarios, each modelling specific interventions or combinations of interventions.
The authors conclude that a combination of interventions addressing the structural causes of exponential growth (in population & economic production) will be necessary to prevent overshoot and collapse. Their recommendations for transition to a permanently sustainable society are:
- Stable global population, in which the average birth rate equals the average death rate.
- Stable industrial output per person. This does not imply that progress is halted and standard of living cannot continue to improve, only that per capita consumption of resources is limited.
- Technological solutions that reduce our ecological footprint by decreasing pollution, conserving resources, and protecting and improving agricultural land.
Limits to Growth places exponential growth in population and economic production / consumption squarely at the root cause of environmental problems. This book is vital to understanding the urgency of the environmental and societal issues we face, and the severity of their potential consequences. If the conclusions of the report are accurate, lack of sufficient intervention threatens not only a few species, or particular ecosystems, but the existence and wellbeing of humankind.
In my opinion this is one of the most important books on environmental issues. Highly recommended.
For further information or to purchase this book, click here > Limits to Growth: The 30-Year Update