Mark Perna, a friend and reader o’ the blog, recently wrote to note that environmental discussions seldom address what he regards as the world’s single largest environmental problem: overpopulation. All other problems, he argues, derive from that one.
He sent me a copy of a paper titled “The Sustainability of Human Populations,” by British physicist Martin Desvaux. Desvaux calculates a carrying capacity for the planet and concludes we’re well beyond it, even if the most rapaciously consuming societies (basically, the West) were to scale back.
I wrote Mark:
“I agree that overpopulation is the elephant in the room in discussions of our multifaceted environmental crisis, but my concern when people raise it is that some are sort of “population fundamentalists,” who emphasize it to the exclusion of the amount and type of consumption people are practicing, and how that varies from society to society.
That tends to lead to demonizing of countries with fast-growing populations, even if they have below-average per capita consumption.
But Desvaux doesn’t do that, and in fact his “carrying capacity” approach is I think a very good way to conceptualize the problem in general.
While he chooses a particular set of data to figure from, his answers seem in line with similar calculations I’ve encountered elsewhere. (Another one places our global “overshoot” year in the early 1980s, while Desvaux says late ”80s, but the fact that they’re so close is significant.)
He’s also the first person I’ve seen do a by-country calculation — giving his own patria a right goosing in the process, and helping emphasize that “developed” nations are merely outsourcing their overexploitation of resources.
I’d append two thoughts. One, developed countries in general and the U.s. in particular must bear the brunt of responsibility for addressing these problems, due to our unconscionable rates of consumption. It’s hard to blame Bangledeshis with large families when one American consumes 25 times as much (or something) as one of them.
Plus, we have the privilege of understanding the problems, and the wherewithal to do something about it (or not do something, as the case may be, if one’s goal is zero/negative population growth).
Second, while Desvaux’s correct that as things stand few Westerners will reduce their consumption voluntarily, I think that if people (or our culture) had some good role models and good incentive to do so, we’d find it’s much easier and much more agreeable than we think. A huge amount of what we consume becomes pure waste — in other words, we’re such overprivileged pigs we don’t mind taking stuff that doesn’t even benefit us (from food that ends up in landfills to lights left burning all night in empty office buildings, for starters). In other words, we could reduce consumption significantly without even feeling it. And further conservation and efficiency measures, I know from experience, are not all that hard either.
But he’s right — we’ll need big disincentives to stop living that way. And without big reductions in overall numbers of humans, even that reduction in overconsumption can only go so far.”
“I get the whole “population fundamentalist” angle. I hadn’t actually thought of it in those terms before. I’m actually more concerned that the “culture of life” that we find ourselves in where “every sperm is sacred” to quote Monty Python, keeps us from discussing the topic in any meaningful way. Any politician who tries to discuss the topic will certainly find himself on the wrong side of someone’s religion. The other issue beyond consumption is that even with amazing advances in food production, there is still a limit to the number of mouths that can be adequately fed.
But you’re right the US has to take the lead and that’s not going to happen without some major incentives or disincentives as the case may be. I’m looking forward to reading whatever you post formally.”
I responded that there are also plenty of problems, and quite dire ones, associated with the level and method of food production we have right now (aquifer depletion, soil erosion, agricultural pollution, etc).
But obviously there are no easy answers here. The main point, and the one Mark originally made, stands: Population control has to be, at the least, one of the things we start talking about, lest nature start talking about it for us.