Changing carbon dioxide intensity

In the previous chapter we saw how business as usual scenarios lead to a rapid increase in the concentration of carbon dioxide in the atmosphere. We saw how GDP per person and population combines with CO2 intensity to give the total emissions to the atmosphere. The population momentum that comes from past high fertility and the falling mortality makes it difficult for policies to have a short-term impact on population. However, there are some examples such as China, which has changed the rate of increase of its population through regulations known as the one-child policy. Population is a field not usually in the domain where engineers practice. Reducing population growth might be a cost-effective way of managing greenhouse gas, as well as addressing a number of other challenges facing the world, but we will not pursue it further. Readers are referred to Birdsall (1994) for a discussion of population momentum.

The first term, involving the GDP per person, is not one we would advocate reducing to control greenhouse gas emissions. Some assert that the people living in the developed nations consume too much and so have too high a GDP. They are profligate consumers! No-one sensible advocates that the poorest reduce the GDP per person. Would a much fairer distribution of wealth help all to have an acceptable level of GDP with no-one living in poverty? Could the global GDP then be lower than at present and so reduce the emissions of greenhouse gases?