This is just a sneak peek from Klaus’ feature in SCENARIO 06:2015. If you are not a current subscriber to SCENARIO or a member of The Copenhagen Institute for Futures Studies, then subscribe or get in touch with us here.
According to the UN’s latest prognosis, the world’s population will grow to 9.8 billion by 2050 and 11.2 billion by 2100. This is a worrisome development, but how worried should we really be?
A few months ago, the UN published its latest world population prognosis for the rest of the century. The prognosis predicts higher population growth than hitherto expected, and this may be a cause for concern. The middle scenario – the one that the UN considers the most realistic – now says that the world’s population will grow by a billion towards 2028 and continue to grow to 9.8 billion by 2050 and 11.2 billion by 2100. The growth is expected to decline towards the end of the century, but not to stop entirely. Half the growth is expected to take place in Africa, which will more than double its population towards 2050 to 2.5 billion. On the other hand, populations are expected to decline slightly in Europe and Japan.
One thing is that there will be more people in the world; another is that the population also grows older. Where today about 900 million people in the world are 60 or older, the UN expects this to grow to 2.1 billion by 2050, corresponding to almost half the overall population growth. This is because the growth in world population is almost as much a result of people living longer as of more people being born. In fact, fertility is expected to decline from ca. 2.5 today to ca. 2.0 by 2050 in developing countries as well as developed countries – a level that all else being equal would mean a stable population. After this, global population growth will solely reflect that each generation lives longer than the previous one.
Even in developed countries, life expectancy increases about two years every decade. In the least developed countries, which today are characterised by high mortality rates among children and youths, expected improvement in living standards will lead to a significantly higher gain in life expectancy. A joker in this development is if scientists manage to break the riddle of old age, hence allowing dramatic increases in life expectancy through drugs, gene therapy or other means. If the majority of the world’s population gets access to such means, it can lead to far higher population growth than in the UN’s middle scenario.
Is it a problem that we have an ageing world population? Probably not. If the older people remain productive longer as they live longer, it may in fact turn out to be a huge advantage to the world economy. Normally, people are a net expense for society for the first 15 and last 10 years of their lives. If life expectancy is 75, this means that only two thirds of a life is productive. If life expectancy is increased to 100 without leading to more unproductive years, three quarters of life will be productive – a relative growth of 50 percent. Even if only half the gain in age is productive, the benefit will be considerable.
Resources for all?
So, we can expect the world’s population to grow by two to three billion over the next 35 years. This raises the question: Will there be enough essential resources – drinking water, food, energy – for all? In 2014, PEW Research asked scientists from the American Association for the Advancement of Science (AAAS) whether a lack of resources would be a problem for the growing world population, and 82 percent responded that it would.
If they are right, there is a morbid self-regulating mechanism in population growth: If a growing population leads to more hunger, unrest and fighting over resources, it will lead to massive losses of human life, which will directly reduce population growth. In 1798, Thomas Malthus predicted in his book Essay on the Principle of Population that precisely these mechanisms would limit the population of our planet if it rose beyond a certain level. However, Malthus’ doomsday prophecies have not come true yet – nor are they likely to any time soon. The real problem will probably not be a true lack of resources, but rather a too unequal distribution of resources – for new technology will by all accounts ensure plenty of resources for a long time to come…