The United Nations and the streets of Manhattan are going into global warming saturation mode, from Sunday's People's Climate March through the Tuesday climate change summit convened by Secretary General Ban Ki-moon and on through an annual green-energy event called Climate Week.
Largely missed in much of this, as always seems the case with climate change discussions, is the role of population growth in contributing both to rising emissions of greenhouse gases and rising vulnerability to climate hazards in poor places with high fertility rates (think sub-Saharan Africa).
That's too bad given that on Monday a separate special session of the General Assembly is scheduled to hold a 20th-anniversary review of actions since the International Conference on Population and Development in Cairo. As Bob Engelman of the Worldwatch Institute mused at a Wilson Center meeting in Washington last week, there needs to be much more crosstalk.
Obviously, rates of consumption of fossil energy and forests per person matter more than the rise in human numbers. As I've said before, 9 billion vegan monks would have a far different greenhouse-gas imprint than a similar number of people living high on the hog.
But family planning, for instance, should absolutely be seen as a climate resilience strategy in poor regions. This is how I put it in 2010:
Africa's population is projected to double — from one to two billion — by 2050. That means exposure to [deep, implicit] climate hazards will greatly increase in many places even if climate patterns don't change at all. So family planning, and sanitation and water management, sure sound like vital parts of any push for climate progress.
I'd be happy to shift my view if someone can explain a flaw in my logic.
Read this timely (and aptly titled) piece by two former United Nations Population Division officials, Joe Chamie and Barry Mirkin for more: "Climate Change and World Population: Still Avoiding Each Other."
For the moment, trajectories for fertility rates, particularly in Africa, are showing few signs of modulating, leading to this sobering title on the latest analysis of United Nations population data, published in the current edition of Science: "World population stabilization unlikely this century."
The study uses models to generate not only a range of outcomes for population through 2100, but also probabilities. Robert Kunzig at National Geographic, who's been writing in depth on human population growth for years, has a superb analysis of this paper and other work, led by the Austrian demographer Wolfgang Lutz, pointing to more modest growth.
What everyone cited in his article agrees on is that Africa is a critical region (read about Nigeria, particularly!) and that women's access to secondary education and contraception are the key to shifted trajectories on family size — and so much else, of course. Please read Lutz's piece on "Population policy for sustainable development" for more.
I reached out to one of the authors of the Science paper, Adrian E. Raftery, a professor of statistics and sociology at the University of Washington, for a final thought on the many benefits of action:
The projected rapid population increase in Africa may well exacerbate a range of challenges: environmental, health and social, including climate change. On the other hand, if fertility decline accelerates, Africa stands to gain many benefits. These include a demographic dividend, which happens when a country experiences a rapid reduction in fertility rates. This leads to a period of 30 years or so when there are relative few dependents (children or old people), and many more resources are available for infrastructure, education, environmental protection and so on. This dividend can be reaped even while population is increasing (albeit more slowly).
If African population growth could be kept to the lower end of our projected interval (3.5 billion instead of the median of 4.2 billion, compared with the current 1 billion), the outcomes would likely be much better. That's another 2.5 billion people instead of 3.2 billion by 2100. It doesn't sound that different, but it could change a lot of things. It's feasible with the right policies.
We know the policies that can help to achieve this. The first is to improve access to contraception. 25 percent of women in sub-Saharan Africa who do not want to become pregnant are not using contraception, and this number hasn't changed in 20 years. The second is to improve girls' education. For example, more than 25 percent of girls in Nigeria do not complete primary schooling.The issues are priorities, resources and political will. Population was a major world concern up to the 1990s (with a peak at the Cairo conference in 1994), but since then has fallen off the world's agenda. This now seems to have been premature. Population should come back as a major world priority. There's a need for the world as a whole to support families and governments in high-fertility countries improve access to contraception and education.
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