It is my impression that Cribb is hoping that if we can just manage the coming population boom to the mid-century, then the birth rate will naturally go down, and the population problem will go away on its own accord.
And if the world’s population were to continue to increase after mid-century, then what? “Green Revolution 3.0” to support a world population of 15 billion by the end of the century, and so on, ad infinitum? If you accept that we live on a finite planet with finite material resources and finite energy, then I think the notion infinite population growth can be rejected outright.
The data includes the US Census Bureau International Database of population statistics from 1950 to present (open black circles) as well as the Census bureau’s population projection to 2050 (solid black line).
Figure 25 illustrates that the 4.2 billion increase in population occurring over the past sixty years (2.6 billion in 1950 to 6.8 billion in 2010) has occurred in the presence of expanding per capita petroleum consumption, peaking at 5.3 b/py in 1979, falling back to 4.3 b/py in 1983 and remaining in a narrow range since then.
If the US census bureau’s prediction of global population increase, and, my prediction of petroleum production rate decrease are both correct, then we should see a dramatic decline in per capita petroleum consumption over the next 40 years from 4.2 b/py in 2010, to only 0.5 b/py in 2050.
Not withstanding the other important factors affecting food production (water, soil, waste etc...) I think that this is roughly what would have to happen if Cribb’s scenario would come to pass.
My population decline now scenario
Table 13: linear correlations between global population and petroleum production rate
Slope (b / bbs per yr)