This blog is intended to go along with Population: An Introduction to Concepts and Issues, by John R. Weeks, published by Cengage Learning. The latest edition is the 12th (it came out in 2015), but this blog is meant to complement any edition of the book by showing the way in which demographic issues are regularly in the news.

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Friday, March 20, 2015

Anthropocene from a Demographic Perspective

Nature News recently highlighted a story from the journal Nature about the growing movement to add a new period of geological time called The Human Age--Anthropocene. Now, to be sure, this is a classification scheme developed by geologists, not by demographers or other social scientists. But let's face it--the only reason why most people are going to be interested in geological time is because it relates back to human existence in some way or another. Andrew Revkin also takes up the issue in his NYTimes blog because, as he notes, he is "on the Anthropocene Working Group of the international geological organization that is pondering the official scientific question and because I proposed we were entering a “geological age of our own making” back in 1992." This latest proposal published in Nature suggests that the Anthropocene began in 1610:
Simon L. Lewis and Mark A. Maslin of University College London* point to the year 1610, marked by, of all things, a sharp but brief dip in carbon dioxide concentrations (revealed in ice cores). The greenhouse-gas decline, they say, is thought to have been the result of the implosion of civilizations in the Americas as European-carried diseases killed off tens of millions of inhabitants of the “New” World. The collapse of agriculture would have resulted in enormous regrowth of forests, and thus the uptake of CO2.
I get it that geologists have their own rules of the game, but from a "real" perspective, the impact of humans began with the scientific discoveries leading to a fall in the death rate, and thus to the startling increase in the number of human beings living on the planet. Those same scientific discoveries--emanating generally from the European Enlightenment--are also at the core of innovations that have allowed us to change the earth's atmosphere in very measurable ways, and the layers of the planet beneath the surface in ways that are less readily measurable, but no less real in their consequences (e.g., water and mineral extractions). The mid-19th century is when these changes became readily apparent and they have been essentially unstoppable since then. 

Another candidate for the beginning of the Anthropocene might be the year the world hit 2 billion people--estimated to be 1927. Why? Because multiple studies suggest that the world could sustain a population of no more than 2 billion people at the current level of living of the US and other rich nations. 

A quick Google search of the term "anthropocene" shows that its use is spreading and that it resonates with a lot of people. It may or may not resonate with geologists, but I have a hunch the term is here to stay and with luck it will help to call attention to what we're doing to the planet before it's too late to save the human species.


  1. Prof Weeks ... this series of comments from you about the Anthropocene is perhaps the most pertinent topic that you have ever posted. We could say that the Anthropocene poses the greatest challenge because of the strange mixture of Demographics, Enlightenment, Human Ignorance, and Human Aggression.

    Personally, I think that we had a chance "in principle" to handle the Anthropocene Era - provided human beings acted with great enlightenment, cooperation, and yes - kindness!! With the scientific age, the age of Internet communications, and the greater understanding between cultures - we had the possibility to really solve the major problems. In order to survive the Anthropocene Era, we would essentially need to convert our planet to sustainable trends, and switch to a broad range of new technologies to produce food, energy and clean water in an affordable way. These are great goals - indeed noble - and they might have been achieved.

    BUT ... we are acting more like "caged animals" than enlightened human beings. Our political systems all over the world - are acting very much with insular thinking (narrow), short-term greed, crisis management, and one-upsmanship. In other words, our global society has structured itself to be "competitive and aggressive", rather than "cooperative and problem solving".

    A key parameter - tat you touched upon - is the sustainable level of human population on this planet. I have seen a variety of estimates, ranging from 2-6 billion ... depending on what you assume is an "acceptable existence" for a human being. But by all measures, we have probably already EXCEEDED the sustainable level. Which means that our planet today is on an OVERSHOOT trajectory for the total global population.

    Therefore, in blunt terms, this means that we will NOT be able to support the lives of the 1-8-2.8 billion people who will arrive on planet Earth in the next 40-50 years. Te mathematics of what happens next is undeniable - these people are guaranteed to have a short and horrible existence in this world. That outcome is directly guaranteed by our current set of policies for how we are operating our global society today.

    ALL THAT WE NEED TO DO - to see an apocalyptic scenario take place ... is to do nothing and allow the current "status quo" to continue.

    Pete, Redondo Beach, CA