Overpopulation and the Collapse of Civilization
By Paul Ehrlich
A major shared goal of the Millennium Alliance for Humanity and the Biosphere (MAHB) and Sustainability Central is reducing the odds that the “perfect storm” of environmental problems that threaten humanity will lead to a collapse of civilization. Those threats include climate disruption, loss of biodiversity (and thus ecosystem services), land-use change and resulting degradation, global toxification, ocean acidification, decay of the epidemiological environment, increasing depletion of important resources, and resource wars (which could go nuclear). This is not just a list of problems, it is an interconnected complex resulting from interactions within and between what can be thought of as two gigantic complex adaptive systems: the biosphere system and the human socio-economic system. The manifestations of this interaction are often referred to as “the human predicament.” That predicament is getting continually and rapidly worse, driven by overpopulation, overconsumption among the rich, and the use of environmentally malign technologies and socio-economic-political arrangements to service the consumption.
All of the interconnected problems are caused in part by overpopulation, in part by overconsumption by the already rich. One would think that most educated people now understand that the larger the size of a human population, ceteris paribus, the more destructive its impact on the environment. The degree of overpopulation is best indicated (conservatively) by ecological footprint analysis, which shows that to support today’s population sustainably at current patterns of consumption would require roughly another half a planet, and to do so at the U.S. level would take four to five more Earths.
The seriousness of the situation can be seen in the prospects of Homo sapiens’ most important activity: producing and procuring food. Today, at least two billion people are hungry or badly in need of better diets, and most analysts think doubling food production would be required to feed a 35% bigger and still growing human population adequately by 2050. For any chance of success, humanity will need to stop expanding land area for agriculture (to preserve ecosystem services); raise yields where possible; increase efficiency in use of fertilizers, water, and energy; become more vegetarian; reduce food wastage; stop wrecking the oceans; significantly increase investment in sustainable agricultural research; and move feeding everyone to the very top of the policy agenda. All of these tasks will require changes in human behavior long recommended but thus far elusive. Perhaps more critical, there may be insurmountable biophysical barriers to increasing yields – indeed, to avoiding reductions in yields – in the face of climate disruption.
To read the full essay, please click here: http://mahb.stanford.edu/blog/overpopulation-and-the-collapse-of-civilization/
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