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After the killing of Osama bin Laden earlier this month, it was tough going for other global issues to get much media space.
One important item to get somewhat lost in the saturation coverage was the release, 36 or so hours after the al Qaeda figurehead's death, of the United Nations' latest review of world population prospects. This was unfortunate as the report holds major long-term implications for humankind.
Just how much more attention it would have got on more normal news days, though, is uncertain, as world population growth these days widely labours under the perception of being yesteryear's problem.
The December 2009 Copenhagen Accord on climate change was an excellent example of this mindset.
Despite the number of humans on the planet having an obvious effect on greenhouse gas emissions and the task of achieving emission reductions, there was not a single mention of "population" or "population growth" in the final 1300-1400-word accord.
With the global growth rate now down from the very high levels of the 1960s and '70s and the apocalyptic demographic predictions of Paul Ehrlich, the Club of Rome and like doom-sayers from those days not having come to pass, the population bomb is widely seen as having been defused.
This is a dangerous misjudgement.
Although the global growth rate has dropped by over 40% since its peak in the late 1960s, there is still a lot of population increase to occur before human numbers can realistically be expected to level off - according to the UN's review, probably close to 1.1 billion or so additions between now and 2025, and then probably about a further 1.3 billion in the following quarter century. With still more to come after that.
For quite a while it has been expected that global numbers would stabilise just above 9 billion in the middle of this century. However, the UN is now projecting the total to reach about 10.1 billion by the year 2100.
While the world would be better off without those additions, nonetheless, it's not so much the projected global increase that's the worry.
The danger in the demographics is that the bulk of the increase is going to occur in countries least capable of handling it - where population pressures are already clearly apparent. Of the 2.4 billion projected to be added by 2050, all but 3% will probably be in less developed countries.
Just concentrating on the 15-year period through to 2025 - as projections for that relatively short time frame can be viewed with greater confidence than those for the longer horizon of mid-century or beyond - reveals 13 countries that are projected to see their populations grow by 50% or more and another 21 where growth is anticipated to be between 40% and 50%.
All up, 24 countries are pinpointed as probably adding 10 million or more people to their populations in the short space of the decade and a-half. With only one exception (the United States), all of these 24 nations are less developed countries.
While significant falls have occurred in birth rates in most less developed countries, "wanted fertility" still remains well above replacement level in many. In turn, even where fertility has fallen close to or below replacement level, the young age structures resulting from previous decades of high birth rates mean substantial built-in momentum for further population growth.
In absolute numbers, the already demographic billionaire India is picked to increase the most, being projected to add nearly a quarter of a billion people by 2025. The country is on an impressive economic growth trajectory and will probably be able to handle those numbers.
But with well over 200 million citizens undernourished and a quarter of the population living under the global poverty line of $US1 ($NZ1.25) per day, the population increase will make things considerably more difficult than if the demographics were not so daunting. Likewise with what will ultimately be necessary efforts on its part to reduce aggregate greenhouse emissions significantly.
The greater worries, however, relate to other places. One has to wonder how Pakistan, for instance, already under enormous social, economic, environmental and political stress, might handle 47 million extra people being added by 2025, which is what the UN projections are pointing towards.
Or Nigeria, gaining a further 71 million in the same period. Democratic Republic of the Congo, 29 million? Ethiopia and Bangladesh, 27 million each? What prospects for Afghanistan, Iraq, Somalia, Yemen, the Gaza/West Bank Palestinian Territories, East Timor, etc being able comfortably to accommodate 50% or larger increases in this short time?
A different concern is the projected 39 million increase to the United States' population by 2025, and then a possible 53 million more in the following quarter century. The worry in this case is the ecological boot-print these additional likely heavy-order consumers will place on the planet.
Unless there are substantial moderating changes to US production and consumption patterns, these additions will make a far greater impost on the global environment than those of Pakistan, Nigeria, Ethiopia, Bangladesh and the Democratic Republic of the Congo combined.
Besides environmental and humanitarian concerns, these demographics have major national and international political and security ramifications through the prolongation of potentially volatile "youth-bulge" population structures in many less developed countries.
A variety of studies have shown that countries with large youth bulges (usually defined as where people aged 15-29 make up 40% or more of the adult population) are especially prone to civil unrest and armed conflict. At present, more than 80 countries around the world have such age structures, and in many these will persist for several decades.
Youth bulges in themselves do not make unrest and conflict inevitable. If a nation's economy can meet the demographic pressure for productive job creation, a two- to three-decades-long youth bulge can be an asset, providing the foundation for sustained economic growth: a workforce "demographic dividend".
But when mixed with high levels of young adult un(der)employment, poverty and frustration at the lack of opportunities for advancement, youth bulges can form a volatile recipe.
Hotspots Afghanistan, Pakistan, Iraq, the Palestinian Territories, Yemen and Somalia are all unfortunately excellent examples.
We are repeatedly shown those conflicts through political, military, religious and ethnic lenses, but no long-term peace and stability will be found in any of those countries until the underlying structural demographics and parallel economic development deficiencies are addressed.
Those countries, though, are by no means the end of the list. There is a whole range of sub-Saharan nations where demographic youth bulges will almost certainly be powerful destabilising forces in the years ahead. Some already have been.
In our own regional neighbourhood, East Timor, Papua New Guinea and several Pacific island states are likewise of concern. We ignore these demographics at our peril.
- Dr Kevin McCracken is an Otago geography graduate. He is a former dean of environmental and life sciences and now an honorary fellow at Macquarie University, Sydney.