Population Linked To Greenhouse Gas Levels

Although a commonly-held belief that humans have a huge impact on our planet, a recently published study highlights the role of population growth and the amount of stress it puts on our environment, most noticeably through greenhouse gases,

"How does population growth influence greenhouse gas emissions?" says co-author of the study, Thomas Dietz. "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."

The debate over the cause of climate change and global warming has usually been about whether or not humans are actually playing a significant role in it or whether it is part of the Earth's natural cycle. Now, the debate has shifted more to "what kinds of human activities" affect our planet the most.

"No single factor acts independently of the others," said Dietz. "The effect of population size depends on consumption; the effects of consumption depend on how many people are consuming at that level."

One claim made in the climate change debate is that the more affluent a country is, the more it consumes, and thus will have a bigger green footprint. However, people in affluent countries tend to be more socially conscious and embrace environmentalism more.

"For example, increased use of electricity generated by renewable sources that do not emit greenhouse gases might partially or wholly compensate for the tendency toward increased emissions that come with increased affluence," explained Dietz.

Human population is projected to reach 10 billion by the end of the century, and the paper's authors called the future "sobering." Our only hope lies in improved technology to cancel out our carbon footprint.

"However, these changes will need to be huge because they must counter substantial increases in scale coming from population growth and especially increasing affluence," they wrote.