[I can't get the graph to work. Follow the link for a similar one]
Professor Ehrlich and Professor Emmott are quite right.
World population is likely to increase from its current 7 billion to about 9.5 billion in 2050 and 10 billion in 2100.  This increase will very probably cause significant problems, which need addressing.
Now I’ve got that off my chest, let’s get down to discussing why the ludicrous Emmott and the Loathsome Ehrlich should be opposed and exposed as the dangerous fools they are.
Three events last year brought Malthusianism back into fashion:
- The Royal Society report “People and the planet “ by Sir John Sulston 
- The election of Professor Paul Ehrlich as a fellow of the Royal Society in April 2012, and the publication (Jan 9th 2013) of his paper 
- The success of the lecture / performance “Ten Billion” by Stephen Emmott and Katie Mitchell at the Royal Court Theatre 
All three documents – the official Royal Society Report; the paper by Royal Society Fellow Paul Ehrlich; and the Royal Court show – offer identical analyses of the problems facing the world. In two sentences: Population increase, economic growth and consumption, plus climate change, will lead to resource depletion and catastrophe. Only massive organised behaviour change can save us from disaster.
There the resemblance between the three works ends.
The Sulston report is a thorough and rather dull scientific assessment of the evidence for this thesis – an attempt to update the anonymous thriller “Limits to Growth” which told us, back in 1974, that we must stop getting richer or face catastrophe. What the Royal Society is doing publishing it , Gaia only knows, but it’s worthy enough, and full of useful diuretic statistics, for those who like that sort of thing.
The Emmott/Mitchell work exists only as a Platonic entity in the reports of theatre critics, and in a three minute video   (though it’s due to be published as a book by Penguin in May). It was obviously wildly inaccurate, but possibly amusing in a surrealist sort of way – a sort of Green Ubu for nerds – which is what you’d expect from a performance cobbled together by a trendy London theatre director and an unworldly Cambridge professor who spent six hours on a high speed train together discussing the ecological cost of fucking lettuce. 
In the forty years that Ehrlich has been prophesying doom, his forecasts have gone from the false to the downright peculiar. Apparently, Climate Denial is a manifestation of “..endarkenment – a rapidly growing movement towards religious orthodoxies that reject enlightenment values”.  I’ll leave discussion of that for another time. (Thanks to SunGCR for the links to Ehrlich he provided in comments to my article . I haven’t used them here, but will certainly do so in a future article).
All three works base their prediction of future population trends on this graph (fig. 2.3 in the Sulston report) based on UNPD 2011. http://esa.un.org/unpd/wpp/Analytical-Figures/htm/fig_1.htm
The UNPD 2011 document is an update of the 2004 report which has population peaking at 9 billion in mid-century and then declining. As I said in our fisking of Emmott  there are suspicions that the 2011 update is deliberately designed to be alarming. While the 2004 document is a proper report, with lengthy discussion of its predictions by experts, the 2011 update is simply a number of graphs with a list of FAQs attached. Only an expert can judge whether its pessimistic upgrading of population estimates is valid or not. But let’s accept it anyway.
The “medium variant” in the graph above, based on best estimates of future fertility rates, gives a total population of about 9.3 billion in 2050, and 10 billion in 2100. Slight changes in estimates of fertility rates (adding or subtracting half a child to estimated family size) give huge variations in population estimates for the end of the century, from 16 billion and rising, to 6 billion and falling. (The grey line, which shows a population of 27 billion, is pure fantasy, based on fertility rates staying constant. Emmott apparently mentioned this figure in his show, and was evidently embarrassed when challenged about it in a post show Q&A session) 
Predicting future population trends is not as absurd as it might seem, despite these wide variations. There are good data for over a hundred countries, and what is known as the Demographic Transition is well understood. Briefly: a rise in living standards leads to a fall in infant mortality, a rise in life expectation, and, later, a fall in fertility (average family size). This process is repeated all over the world in countries of differing religions and cultures. The uncertainty in estimates of future population comes from the time lag between lower infant mortality and lower fertility. There’s a period of maximum population expansion, lasting a matter of decades, when life expectancy goes up, infant mortality comes down, yet fertility remains high. Then it drops, and population levels off and start to drop a generation later. Hence population is declining in Europe, levelling off in Asia and Central America, and still rising in Africa, despite the fact that fertility rates are dropping there too, sometimes spectacularly.
All this and much more is brilliantly explained at Professor Hans Rosling’s delightful site Gapminder .
Declining fertility is correlated with economic development, but with a lot of other things too, making identification of cause and effect a delicate business. Countries where fertility remains obstinately high include Afghanistan, the Congo, Palestine, and among the Arab and Jewish Orthodox population of Israel. Professor Emmott’s proposal of universal gun ownership for children as a solution to the population problem is clearly not a good one. War and unresolved political conflict cause population to increase.
Literacy, particularly female literacy, is clearly an important factor, and I’d naively assumed, as I imagine had many other people, that it’s all about women being able to read the instructions on the contraceptive packet.
Then Tim Worstall pointed me to an article from way back in 1994, Lant Pritchett: “Desired Fertility and the Impact of Population Policies” , which overturns everything you thought you knew about population growth. It demonstrates, as clearly as anything can ever be demonstrated in the social sciences, that the key driver of fertility rates is the parents’ optimum desired family size, accounting for 90% of variance. In other words, women have the number of children they want to have. Of course, literacy, economic development, availability of contraception, government health campaigns, etc., have an effect, but not much, or at least, not directly.
The article is a delight to read, and if your reading of scientific papers has been limited to the field of climate science, it’ll be an eye opener. In his quaint old-fashioned way, Pritchett puts forward the evidence for his hypothesis, and then proceeds to look for flaws in it. (For example, how much faith can you put in surveys into ideal family size in a country like Yemen, where 30% of women, when asked: “How many children would you like?” reply “Allah will decide”?) I looked around the net for refutations. As far as I could see, Pritchett’s work has been politely ignored. (Perhaps the fact that he was born in Utah and graduated from Brigham Young University has something to do with it? Surely not.)
This is embarrassing. Demographic research is carried out by or on behalf of governments, UN organisations, and university departments whose financing depends on the discover of problems and their possible solutions. If it turns out that women have kids because they want them, and they stop having them when they don’t want them any more, an awful lot of academics and bureaucrats, not to mention think tank personnel, NGOers and marketing men, are going to find themselves at a loose end. Of course, we still need contraceptives, and nurses and doctors to administer them, and clinics and hospitals and roads to get there and electricity to power them – economic development, in other words. What we clearly don’t need are vast international programmes of education and indoctrination. What we don’t need is the Royal Society and their pontificating Professors. Women will decide. Maybe on the advice of the local nurse, maybe out of a desire to participate more fully in the development which their country is enjoying, maybe inspired by watching DVDs of Desperate Housewives – how would I know? How would you know? How, above all, would a United Nations bureaucrat know?
The neo-Malthusians have a big problem getting over their message. Almost all the coming population growth will be in Africa. How to sell population reduction without raising the spectres of colonialism and racism? The answer, of course, is to link it with global warming, resource depletion, deforestation, and species loss. “It’s not that we’re worried about too many Africans, you understand. Of course not. But what happens when you multiply population increase by increased wealth (which of course we earnestly desire) and subtract the raw materials and agricultural land from what we have? Where will the rhinos go?”
Here’s a table of population for a sample of the major countries of the world, for 1950, 2011 and estimated for 2100. 
Country 1950 2011 2100
Australia 8 22 35
Canada 13 34 48
France 41 63 80
Germany 68 82 70
United Kingdom 50 62 75
United States 157 313 478
Russia 102 142 111
Japan 82 126 91
Brazil 53 196 177
Afghanistan 8 32 110
Bangladesh 37 150 157
China 550 1,347 941
India 371 1,241 1,550
Indonesia 74 242 254
Iran 17 74 62
Iraq 5 32 145
Pakistan 37 176 261
Algeria 8 35 39
Burkina Faso 4 16 96
Congo, Dem Rep 12 67 212
Ethiopia 18 84 150
Kenya 6 41 160
Malawi 2 15 129
Mali 4 15 80
Niger 2 16 139
Nigeria 37 162 729
South Africa 13 50 54
Tanzania 7 46 316
Uganda 5 34 171
You see what I’m driving at. There are countries in Africa you may never have heard of which, sixty years ago, had the populations of an average British county, and which by the end of the century are predicted to be twice the size of the UK. There are Moslem countries like Iran and Algeria, reputed to be centres of obscurantism, where the population explosion is all but over. Fanatical Iran has the same development potential as Europe. Iraq, on the other hand, recently liberated from dictatorship and set on the path of western-style democracy, is suffering a demographic explosion similar to that in the Congo or Afghanistan.
By the end of the century, Europe will be perhaps twice or three times as rich as it is now, with roughly the same population. Africa will be five or ten times as rich, but with four or five times the population. Hence the fantasies about tens of millions of climate refugees.
Professor Sir John Sulston is undoubtedly an immensely civilised chap, and Professor Ehrlich has a vast number of learned references to his paper, and Professor Emmott certainly has a huge brain. But the appeal of their thesis lies elsewhere, in the fantasy view of Africa held by us, their public, the semi-over-educated chattering classes of the Western world. We vaguely perceive a vast safari park full of giraffes and rhinos, with a sprinkling of goldmines, gas fields and tastefully designed motels. And somewhere, just out of sight, several hundred million people living in tin hut cities the size of London.
There are fascinating differences. South Africa, currently about the only sub-Saharan country vaguely familiar to most of us, will be dwarfed in size by Nigeria and Tanzania. Maybe it won’t happen. Maybe other things will happen, possibly some of them terrible, maybe even as terrible as the wars that ravaged Europe during the period of the continent’s alphabetisation – the period we think of as the Enlightenment.
Let’s hope the rhino survives. Let’s hope that Africans manage to surmount the problems they undoubtedly face with a minimum of pain. Let’s forget about the dangers of warmer weather and start thinking seriously about the future of the world.
Take Mali, for example, where the Western world has been plunged into one of its frequent bouts of bedwetting by a few hundred tribesmen in jeeps. Thirty of them turned up on a gas field in Algeria, threatening to blow up a major source of Europe’s energy supply. It was undoubtedly a serious situation, efficiently dealt with by the Algerian Army, whose failure to rescue a score or so out of six hundred hostages is being treated in the Western press as a crime against humanity.
Mali, where the French army (2,000 of them) are efficiently dealing with a few hundred bandits, will see its population go from 4 million to 80 million rather faster than the UK made a similar bound in the past couple of centuries, thanks largely to medical progress. We think of those two centuries during which our population leapt from a few million to its current 62 million as a rather successful time in our history, on the whole. Maybe the inhabitants of Mali feel similarly about the present.
Mali was the centre of a major West African empire in the 13th century, apparently. Until recently it was relatively wealthy because of the flourishing cotton industry, which has been all but destroyed by US protectionism. But it has gold and other resources. The US has been training its army in order to resist possible Islamic disruption. Last year, half the US-trained army staged a military coup in the capital in the south, while the other half deserted to join the Al Qaeda-inspired terrorists in the north. 
I’ve been following coverage of the French intervention in Mali and the Algerian hostage drama on French TV, which, I imagine, has been much like TV coverage around the world - journalists and experts sitting round a table and speculating in front of a large screen with the same images passing in a loop. One of the faces round the table will normally be brown – an Algerian energy expert or a journalist from “Jeune Afrique”. From time to time the French journalists will turn to him, he’ll explain politely that they haven’t the foggiest idea what they’re talking about, they’ll listen politely, then go back to their speculation.
In 2100 the population of Mali will be greater than that of France or the United Kingdom, and they’ll be richer and better educated than we are now. What will that world be like? Maybe it’s time to start speculating about that. Maybe it’s time to forget about Emmott’s dreams of arming his children against the hordes of climate refugees, and Ehrlich’s Royal Society fantasies of Endarkenment, forget about the dangers of warm weather, and start thinking about the world we will be sharing with our intellectual and demographic equals.
 discussed at
and on this blog, passim
Katie Mitchell: “He just looks at the world in a completely different way. So if you have a salad with him, he tells you about all of the processes by which the fucking lettuce got onto your plate. So it’s – you can see now I’m a bit, you know, low. It’s because I did about six hours travelling with him yesterday. So I had to look at the world from his devastatingly depressing point of view.”
 transcript at
Royal Court video no longer available