This post follows from a previous thread The Myth of Sustainable Growth, which centred around a video/presentation by Prof Albert Bartlett on the simple maths of growth. There was some email correspondence about this as well as many comments.
It is really just an excuse to play with Gapminder, which is curiously addictive. Basically I’m just looking at factors that influence population and need to be considered in how we would reach “a sustainable population”. Unlike ‘sustainable growth’ (which IMO is logical fallacy if by ‘sustainable’ you do really mean ‘for a very long time’) this is something that likely will happen, and without the predicted doom and gloom. Or perhaps I’m just an optimist.
First, what is Gapminder and how does it display the information?
If you click on the image below it will take you to the interactive version. By sliding the date bar at the bottom, below the x-axis, you can vary the data by date. By doing so you can see that for most countries prosperity, as measured by income per person, has increased. Population growth tends to drop as countries become more prosperous. From around 1970, several European countries drop into negative population growth – some permanently others bounce up and down. Clearly many factors are at play.
A brief look at Ireland’s population changes
Near neighbour to the UK, Ireland is one of the countries that bounces up and down and we can look at the causes, in fact we may be quite familiar with them.
The birth rate was >20 births per 1000 up to 1984 after which it fell steadily – why? In the UK we’ve grown up with stories of Irish girls travelling to the UK for abortions. Contraception was illegal in Ireland from 1935-1980, after which it was available but with strict controls that gradually relaxed. Younger generations have embraced contraception while their parents had fallen in line with the teachings of Catholicism that artificial contraception was immoral, so from 1980 we see a gradual drop in birth rate to about 14 per 1000 today.
Other factors generally affecting population growth are life expectancy (health), availability of resources (food, water) and immigration or emigration rates.
Ireland suffered net emigration in the 1960s for economic reasons. Again the migration of Irish workers to the UK is firmly established in both cultures (the link provided gives a fascinating account). Going back further we can see how emigration has dominated Irish culture for the last >100 years, starting with the Irish Potato Famine. In fact it is quite shocking to note that the population in the 1960s was half that before the famine:
The 1841 census showed that there were 8,175,124 people living in the four provinces of Connacht, Leinster, Munster and Ulster. Only 40 years later, this figure had fallen by over 3 million to 5,174,836 at the 1881 census, 63% of the former value. This figure continued to fall to a recorded historical low of 4,228,553 by 1926.
The population increased slowly to a figure today of about 5,602,603, this is made up from 3,917,336 in the Republic of Ireland (Census 28 April 2002) and 1,685,267 (Census 29 April 2001) in Northern Ireland. Source: Ireland’s Population in the mid 1800′s
IN more recent times it is economic forces that are at play again. With economic boom, from 2004–2006 Ireland had one of the fastest growing populations in Europe, with annual growth rates exceeding 2%. This can be attributed to low death rates, high birth rates and immigration, notably from Eastern Europe. In fact if you visit Ireland (as we did on a family holiday this summer) you’ll find the hospitality industry awash with slavic accents. This work tends to be seasonal, as does agricultural work, but many are staying. Then there is the issue of asylum seekers, many of whom arrive pregnant (Ireland automatically grants citizenship to children born in there). Overall this creates a huge dilemma for the country.
Many Irish people believe the country’s history of migration means they have a duty to extend a warm welcome to people coming to settle here. Read more: Ireland struggles with immigration issue (2004)
The birth rate is currently more than double the death rate, which is highly unusual among Western European countries.
Overall in Ireland we see a number of social and economic factors at play in a country where food, water and major disease or health issues are no longer primary causative factors in population growth or decline.
What about elsewhere?
Crop failure and famine decimated Ireland’s population in the distant past, and we see the same – mass emigration – in some areas today. This is notable for example in Sudan, Ethiopia and other areas in East Africa which periodically suffer famine. However, nutrition has generally improved over the last fifty years, even in developing nations.
If we take a look at population growth in terms of birth rate and life expectancy, the birth rate is falling and people are living longer in most places. This is true of Ireland too; the graph below however, also shows the tragedy of AIDS in Africa.
Taking Swaziland and South Africa as examples we certainly see a dramatic fall in birth rate; life expectancy increased from just over 40 years in the 1950s to >60 years in 1990 before falling back due to AIDS. Better health provision in South Africa may account for the less dramatic fall in South Africa.
War too shows up sometimes in its effects. We can see the sudden, dramatic effects in the economy of Rwanda of the genocide in 1994. More surprising is the temporary baby boom in Luxembourg just after WWII. This isn’t apparent in neighbouring Belgium or Netherlands – anyone know the causes?
Anteros in previous comments posted a link to an article in the Washington Post entitled Five myths about the world’s population posted in las week of October with the world population reaching 7 billion:
Sure, 7 billion is a big number. But most serious demographers, economists and population specialists rarely use the term “overpopulation” — because there is no clear demographic definition.
It goes on:
…if population density is the correct yardstick, then Monaco, with more than 16,000 people per square kilometer, has a far greater problem than, say, Bangladesh and its 1,000 people per square kilometer.
Below we can see Monaco, Bangladesh and many others. The traces indicate the change in population density since 1961. Interestingly Russia has had both increases and decreases and Brazil, proportionally has seen a greater increase than China.
If we look at urbanisation we see how Hong Kong, Brazil and Bangladesh in particular really take off. China too.
But is urbanisation really something to worry about or is it just an inevitable consequence of human development?
Back to Bartlett
His presentation asserts that we should be very concerned about population growth. When I first sent it to a few people, Max Anacker responded at length and managed to express very well what I was thinking but had not managed to put into words:
The underlying message (for the young students in the audience, as well as others watching the video clip) was that we must stop growing our world population and per capita consumption (viz. affluence, GDP, etc.), especially in the USA.
Improving efficiency, eliminating waste and real pollution all make sense (and will happen largely by themselves for economic reasons), without any draconian “top-down” measures, but I saw between the lines on Bartlett’s arithmetic a call for controls on growth to ensure sustainability.
I personally think this is silly.
First of all, we see that it cannot be justified based on global warming fears.
Can it be justified based on fears of overpopulation and a drastic reduction in quality of life.resulting from this?
Or do we live in a self-correcting world, that is driven by market forces?
Isn’t the worst thing that could happen to us a drastic reduction in our affluence (or per capita GDP) some day in the future (maybe) if growth remains unbridled and exceeds our capacity to create more wealth? And the “solution” to the “problem” is to take that cut in affluence today, in order to avert it (maybe) some day in the distant future? Seems silly.
Sustaining the World Population
Optimism favours Max’s ‘self-correcting world’. We can see in individual countries what drives population dynamics. The answer should not be to limit population but to work on the positive drivers for reducing increases. We know what those are – access to adequate food, clean water, better healthcare and reduced disease, increased prosperity and choice in family planning. We’ve achieved amazing technological feats and great understanding has given us the means to grow more food and fight disease. We are in the process of using that knowledge to help the developing world develop. It is our prosperity and humanity that drives that. Perhaps what some need is not more eco-zeal, but more patience.
[P.S. Huge thanks to Kevin for originally introducing me to Gapminder. We've fantasized about what surface temperature would look like on in this format, especially if there was a way to interface it with growth, urbanisation and the quality of the station data. I guess we can dream. ]