How Our Growth-Hungry Economy Has Devastated the Planet -- And How We Can Change Course
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The connection between GDP and the use of materials and energy raises a subtle but important point. When we discuss “economic growth” in this book, what we’re really concerned with is not GDP growth per se, but the increase in material and energy use that comes with GDP growth. Ultimately, the flow of materials and energy is what impacts ecosystems, not the exchange of dollars and cents (although the latter drives the process).
What is the environmental upshot of this growth? Plenty of evidence suggests that the global economy is now so large that it is undermining the natural systems on which it depends. This evidence presents itself as a wide range of global environmental problems: climate change, biodiversity loss, stratospheric ozone depletion, deforestation, soil degradation, collapsed fisheries—the list goes on.
In a landmark study published in 2009, Johan Rockström and his colleagues at the Stockholm Resilience Centre showed that the economy is placing an excessive burden on the biosphere. In reaching their conclusion, the researchers analyzed nine planetary processes that profoundly influence life on earth:
1. Climate change
2. Biodiversity loss
3. Nitrogen and phosphorus cycles
4. Stratospheric ozone depletion
5. Ocean acidification
6. Global freshwater use
7. Changes in land use
8. Atmospheric aerosol loading
9. Chemical pollution
Where sufficient data allowed, the authors of the study determined how far humanity could go in altering these processes and still avoid dangerous levels of disruption. They were able to define “safe operating boundaries” for the first seven processes in the list above. A safe operating boundary is a sort of safety threshold—stay below it, and humanity incurs a low risk of abrupt and hazardous environmental change; go beyond it, and humanity faces a high risk. For three of the planetary processes (climate change, biodiversity loss, and the nitrogen cycle), humanity is now exceeding the planet’s safe operating boundary, and by a large margin in some cases. The potential consequences are severe: the authors warn that transgressing one or more of the planetary boundaries could lead to catastrophic changes at the continental to planetary scale.
Figure 2.3. Humanity is exceeding the safe operating boundary for three planetary processes: climate change, biodiversity loss, and the nitrogen cycle. Biodiversity loss is so far beyond the safe operating boundary that there's not enough space to draw it on this chart. Note that the safe operating boundary is measured differently for each planetary process.
Other analyses, such as those conducted by the Global Footprint Network, corroborate the Rockström study. The ecological footprint is a measure of how much biologically productive land and water area a population requires to produce the resources it consumes and absorb the wastes it generates. According to the latest data, humanity uses 50 percent more resources than the earth can regenerate over the course of the year. This situation is called “ecological overshoot,” and it’s akin to living in debt. We can only continue to consume at our current rate by liquidating the planet’s natural resources or overwhelming its waste absorption capacities. For example, we can cut forests faster than they can grow back and emit carbon dioxide faster than it can be absorbed by oceans and forests. Although we can behave in this way for a short time, ecological overshoot ultimately depletes the resources on which our economies and societies depend.
Indicators like the ecological footprint and scientific analyses like the planetary boundaries study suggest that the global economy has become too large for the encompassing biosphere. So long as this situation continues, we are risking environmental catastrophe. Even if we manage to avoid environmental collapse, the steady depletion of resources threatens to reduce the long-term carrying capacity of the planet, and with it the capability of future generations to flourish.