Hania Zlotnik assesses two polarized takes on population growth and planetary capacity.
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High-rise apartments tower in front of a breeze-block sprawl in Rio de Janeiro, Brazil.
In June, the United Nations Population Division announced that the world's population could grow from 7.2 billion today to 9.6 billion by 2050, assuming that global fertility continues to decline. Such growth constitutes a fundamental challenge for humanity, and now two thoughtful but very different takes on it explore the implications.
In Countdown, Alan Weisman, a journalist probing whether a sustainable balance between nature and the human population can be achieved, offers a key message to guide future action. He avers that no matter what environmental, ecological or social problem we face, it will be easier to solve with fewer people. His book provides an array of examples on how to reduce population growth and, in the process, improve prospects for future generations. He makes a strong case for slowing global population growth — and even for reducing overall population numbers — as a prerequisite for achieving a sustainable future.
Stephen Emmott's 10 Billion takes for granted that the population will continue to grow, and is much less sanguine about humanity's chances of avoiding looming crises. Emmott, head of computational science for Microsoft Research in Cambridge, UK, leads an interdisciplinary group of scientists engaged in addressing fundamental problems through complex modelling. His slim, even terse book — based on his 2012 stage show, which presented his view on the “unprecedented planetary emergency we've created” — primarily examines the transformation of the global environment by human activity, a transformation that includes climate change, increasing water shortages and growing urbanization. Emmott's assessment of the capacity of people and technology to prevent the global crises that confront us is grim.
Weisman's book, by contrast, offers hope. Countdown emphasizes that it is possible to curb population growth by voluntarily limiting family size. He describes how societies as different as those of Costa Rica, Iran, Japan, Kerala in India, and Thailand, have managed to reduce the number of children per woman through the voluntary use of contraception, buttressed by strategies to promote the adoption of a small-family norm — for example, by engaging opinion makers such as government leaders, religious authorities and media icons. Weisman explains that providing contraceptives to the quarter of a billion women worldwide who wish to prevent pregnancy but are not using effective contraception would be the first order of business.
“Weisman describes in harrowing detail the consequences of persistent high fertility.”
It will also be essential to shift attitudes away from prizing high fertility. To illustrate the barriers preventing rapid fertility reductions, Weisman cites the examples of Gaza, Niger, Pakistan and the Philippines, where a combination of religious beliefs, pro-natalist ideologies, the low status of women, weak health systems and a lack of easy access to effective contraception can lead to an average of five or more children per woman. He describes in harrowing detail the consequences of persistent high fertility, with respect to both its detrimental effects on the well-being of individuals and the negative impact of rapidly increasing numbers of people on the survival of other species and the integrity of essential ecosystems.
An important part of the narrative in Countdown hinges on how past predictions of an imminent population collapse caused by limitations in natural resources have not come to pass, largely because technology has removed those limitations, at least temporarily. Both 10 Billion and Countdown provide ample evidence that such revolutionary technology is itself causing new forms of environmental stress. The strains of wheat and rice that led to the 'Green Revolution', for instance, made it possible to feed an ever-growing world population; but the crops are thirstier, which is depleting water reserves, and also demand the use of fertilizers, which are a source of pollution.
Both Emmott and Weisman consider that curbing consumption is essential for long-term sustainability, and both despair at the lack of a concerted effort to achieve it. Whereas Emmott does not present ways to address our failures, Weisman's emphasis on expanding access to contraception as the next-best strategy is both pragmatic and workable, as past efforts have shown. It is to be hoped that his message may be heeded sooner rather than later.