“How does population growth influence greenhouse gas emissions?” Dietz asks. “Well, in looking at most nations of the world during the last few decades we find that for each 1 percent increase in population, we get a bit more than a 1 percent increase in emissions.”
And with the Earth’s population projected to reach 10 billion by the end of this century, “it unquestionably will add to the stress we place on the planet,” Dietz says.
Dietz and Rosa write that they are not optimistic about the future, calling the paper they wrote “sobering.”
“The population and economic growth that can be anticipated in coming decades will tend to push emissions substantially upward,” they write.
The only possible saving grace, they say, is improved technology and changes in the way humans use resources.
“However, these changes will need to be huge because they must counter substantial increases in scale coming from population growth and especially increasing affluence.”