I don't object to the "green sex" that my roundtable colleagues Alisha Graves and Alex Ezeh advocate—if "green sex" simply means that societies should help couples acquire the means and information necessary to prepare for, or avoid, childbearing. But I continue to believe that it's a mistake to exaggerate population's role in carbon dioxide emissions.
Indeed, population size is only loosely related to carbon dioxide emissions, and many forces exceed population in their importance to addressing climate change. After all, though "green sex" may slow population growth, it cannot guarantee that people's behavior outside the bedroom will be "green" at all. Green behavior, broadly defined, is the most critical factor in climate change mitigation and adaption.
Perhaps my point will become clearer if I compare carbon pollution with endemic disease—which, if regarded from a certain perspective, is itself a form of pollution. Both carbon pollution and endemic disease degrade humanity's environment. Both threaten health and life. But the threat of endemic disease doesn't necessarily increase as population grows. The proof of this is that human population today is at an all-time high—but because hygiene and medicine have advanced so much, terrible diseases such as smallpox and malaria have been eliminated or contained. Human beings, despite their record-high numbers, are today under far less threat from communicable disease than when, say, bubonic plague killed one-third of Europe's population.
Improvements in hygiene and medicine are both strongly related to good governance, whose importance I have already emphasized in this roundtable. Bad governance can allow endemic disease to rampage—and carbon pollution to grow unabated. It can cause far worse problems than "overpopulation" can. With good governance, meanwhile, society's burdens can be relieved despite temporary demographic burdens.
Admittedly, because the world isn't and won't become "flat," good governance is more difficult to achieve in some regions than in others. In some poor nations of Africa and West Asia, the prospect of good governance is dimmer than in, for example, the world's emerging economies. Carbon pollution isn't a severe problem in Africa and West Asia—but endemic disease, clean drinking water, and the depletion of arable land often are. For the people who live in such places, these forms of "pollution" are much more dangerous and deadly than carbon pollution is.
It's fine to put forth ideas, such as "green sex," that might help address carbon pollution. But I maintain that the solution to climate change will be found in the economic and social structures largely determined by governments—particularly great power governments. It's governments that can do the most to institute low-carbon energy systems such as nuclear energy. In 2014, nuclear energy accounted for only 4.4 percent of world primary energy consumption. If that percentage rose to, say, 40 percent—roughly, nuclear energy's share in France's primary energy consumption today—while low-carbon energy sources such as wind, solar, and hydroelectricity were also further developed, global carbon emissions could decrease even if population markedly increased.
Population, in and of itself, isn't the core of the carbon problem or any other problem on Earth. The core of global problems such as climate change is actual human behavior. And behavior outside the bedroom should be the main focus of climate mitigation efforts.