Overpopulation and Climate Catastrophe: An economist view

If you know me or have visited this blog before, you’ll know that my book, The Hydra, is about overpopulation. In it, a scientist decides the world is so full of humans, that he must save the planet by engineering and releasing an infertility virus. I won’t give away too much of the plot, but suffice it to say as a novel it doesn’t really do much hard number crunching. It begs -but perhaps never really comprehensively answers- the crucial question: Is the world so overpopulated that we’ll destroy the planet unless we change our policy direction?

Indeed, when you discuss the issue with most people, you get lots of uninformed opinions, which range from “I think we’re all doomed, unless there’s some major war or something” to “There are definitely not too many people in the world. It’s just a question of sharing out the world’s resources fairly and investing in technology instead of war” I always find it astounding just how convinced both sides can be of their opinions, without the faintest notion of what the hard numbers are saying.

So let’s see if we can do any better. First stop, the databank of the World Bank where, after some data cleaning, we can come up with a list of useful data for the world’s countries, grouped into categories depending on how rich they are. Basically we’re looking at four things: population, Greenhouse Gas (GHG) emissions, GDP and birth/death rates, from 1960 to 2015.

What can we see from the numbers?

The first thing to look at is Greenhouse Gas (GHG) emissions. By 2012 we humans had pumped about 567 gigatonnes of CO2 equivalent (GtCO2) into the atmosphere since the dawn of industrialisation (1870). In 2012 alone we added 52 GtCO2 to this stock, up from an annual total of 27 in 1970. While the data are jumpy, on average, the amount of carbon we release in the atmosphere annually is growing by about 1.3% a year. Even if this pace of annual emissions growth were to fall from 1.3% to 0% a year, that would still mean we would be adding the 2012 payload of 52 GtCO2 into the atmosphere every year. If that level of emissions were to continue until 2050, that would result in an atmosphere laden with 2,572 GtCO2 released by humans. That number is so big, it is literally off the charts, as far as the climate scientists are concerned. To illustrate, I’ve made a simplified version of “the chart”, i.e. the UN’s reckoning of how cumulative emissions will raise temperatures. You can find the full chart on page 54 of this document.

The UN shows what sort of temperature changes we'll get in 2100 for given levels of emissions up to 2050
The UN shows what sort of temperature changes we’ll get in 2100 for given levels of emissions

As you can see, they don’t even consider a scenario in which we keep emitting the level of GHG which we emitted in 2012. What this is telling us is pretty clear: if we continue with business as usual, we’re going to miss the current climate targets by more than a factor of 2, resulting in massive, truly massive, changes to our climate which may well spell disaster for the planet and for us all. Now of course, nobody believes business as usual is an option, which is why we had Kyoto and then Paris and soon Marrakesh.

Linking emissions to income

Money makes the world go round. And it also determines how much GHG we put into the atmosphere. Or more precisely, the things people like to spend money on: heat, bigger houses, clothes, high-protein food, transport. The precise link between income and emissions depends on where a person is on the income scale: For very rich countries, there is already evidence of ‘decoupling’, i.e. as rich people get richer, emissions don’t increase, they actually go down. But because rich countries only account for 15% of the world’s population, that doesn’t really matter. What matters are the middle income countries, places like China and Brazil, who make up 35% of the world’s population. The 2.6 billion people living in these countries have been getting richer since 1990, and whenever they’ve got their extra cash, they’ve burned it and pumped it into the atmosphere. Here’s the chart that shows it:

upper-middle-income
This chart shows growth in GHG emissions and growth in per capita income for “Upper Middle income” countries like China and Brazil

As these countries get to the sort of income levels the rich world has already achieved (and they are well on their way) there is every reason to assume that they too will ‘decouple’ emissions from growth, but for now, they are still hungering for more of the things that make the atmosphere hot: steak, cars, swimming pools and city breaks. And this is set to go on into the foreseeable future.

The real problem, though, is the next wave of countries, the so-called “Lower Middle Income” countries like India, which as a group are home to even more homo sapiens (2.8 billion or 40% of the world’s population). If these countries grow in the same way as China and Brazil have done, it will mean even more pressure to emit.

The power of econometrics can help us to estimate this relationship, which turns out to be very well approximated by the equation [kilograms of emissions / per person] = 1090 + (0.7093)*[GDP/person] – (0.0000047025)*[GDP/person]^2 – (0.00000000010531380)*[GDP/person]^3. If you want the nerdy details of where I got this, click here, but for everyone else I’ll just summarise what this means: If you have zero income, you will still emit about 1,000 kg of CO2 equivalent into the atmosphere every year. Emissions go up at about a rate of 700 grams a year for every dollar of extra income you get, but this slows down as your income approaches $35,000 a year. After that, extra income leads to lower carbon emissions per year. Here’s what the graph looks like:

The graph shows that when incomes grow beyond about $35,000, the link to emissions is broken, i.e. 'decoupling'
The graph shows that when incomes grow beyond about $35,000, the link to emissions is broken, i.e. ‘decoupling’

So what about population?

In 2015, there were 7.3 billion humans on Earth, more than ever before. This population increases about 1.2% a year, and while the rate of increase has been slowing since the late 1960s, it hasn’t been slowing by very much. If the pace of population increase we have observed since 1969 were to continue (i.e. let’s assume it continues slowing a bit every year, like it has been doing) there would be 9.75 billion of us by 2050. This, by the way, is the EXACT baseline estimate for the UN’s own population projects, but more about the UN’s numbers in a bit.

The main driver in the growth of populations is the crude birth rate, which measures how many children are born per 1,000 people. It turns out there’s a pretty stable relationship between birth rates and per capita GDP. Crude birth rates have been going down pretty much everywhere in the world, and it’s because of money. Basically, the richer a country, the fewer babies they make. In very poor countries, crude birth rates are around 35-40; as a country gets richer, the birth rate falls to just under 10. Figure X illustrates the relationship, which mathematically can be approximated by this formula: b = (45 * minY^a)/Y^a, where b = birth rate, Y is per capita GDP, and a is a “shape parameter” which is somewhere in the range of 0.2622 to 0.36487 Again, for the nerds out there, all the details are here.

The other thing that affects population is the death rate (deaths per 1,000 population). This too is ultimately a function of cash, but the relationship’s a little trickier because of demographic effects. (For example, Germany’s death rate is higher than Zimbabwe’s, not because Mugabe has better health policies than Merkel, but because, when you break it down, old age is the single worst thing for your health, no matter how rich you are. And Germany simply has a lot more old people than Zimbabwe.)

But here again, statistics can come to our aid. We can isolate the effect of the demographics and when we do, we get a pretty similar relationship as with per capita income. This is the equation that tells the story: d = (minY^a)/Y^a * (1/AGE^g), where d = the death rate, minY is a constant equal to 1,011, Y is per capita GDP, AGE is the percentage of the population aged over 65 and a and g are shape parameters equal to 1.0144 and -2.0097 respectively. In other words, the richer a country’s people are, the lower its death rate. The more oldies are in a country’s population, the higher the death rate.

So to recap, as people get richer, they have fewer babies, but they also tend to live longer, and we can use statistics to estimate by how much this is so for every extra dollar of income they get.

Putting it all together

Equipped with the three sets of estimations we have done above, we are ready to put the whole picture together. The first step is to make an assumption about how per capita GDP might evolve in the future. Of course we don’t know, but let’s imagine it continues to grow at the same annual rate it has been growing from 1990 to 2015, for the four classes of countries the World Bank identifies: high income (e.g. the US and Europe), upper middle income (e.g. Russia, China and Brazil), lower middle income (e.g. India and Indonesia) and low income (i.e. mostly sub-saharan Africa). This is what we would get:

projected-gdp-capita

The dashed green line illustrates the ‘decoupling’ threshold, i.e. the point beyond which getting richer no longer causes more per capita emissions. As you can see, while the ‘Upper Middle Income’ countries pass this threshold, the ‘Lower Middle Income’ countries – and remember in population terms these are the big guys – won’t even have got there.

Using our equations which we estimated above, let’s now link this assumed GDP/capita path to what we know about birth rates and death rates and see what that gives us for total population:

gdp-driven-population-estimates

Now, there’s an awful lot to say about these “GDP driven” estimates of total population on earth. The first thing is that it gives us an estimate of 11.4 billion for the 2050 population, which is a good 1.7 billion more than the UN’s estimates. When you compare the two sets of projections line by line, you see that the differences are in the two “Middle Income” categories. The UN’s estimates seem to assume that these countries population’s will grow more slowly, driven by a faster decrease in birth rates.

The next major difference is that unlike the UN’s demographic projections, these GDP driven projections show no sign of population levelling off any time soon. Indeed, it seems to imply that for the bulk of countries, there’s a good ways to go until death rates overtake birth rates. (I’m willing to put my hands up and say I’m not a demographer, so maybe there’s things I have missed. For one thing, my modelling takes no account of migration trends. I guess I’m kind of assuming that for the world as a whole, net migration is zero. But as people move from poor to rich countries, their birth rates also change, so it’s possible to argue with my numbers).

Now you might be tempted to say: hang on, you just assumed GDP would grow like that. What if growth levels off? Wouldn’t that solve the problem?

Not really. If we change the model so that there is zero growth in per capita GDP from now until 2050 for all four classes of countries, here’s what we get:

If you believe my model, zero growth means even more humans on the planet
If you believe my model, zero growth means even more humans on the planet

Now the 2050 population is projected at a whopping 13 billion! This is because the lower per capita GDP among the ‘middle income’ countries is driving higher crude birth rates.

Finally, let’s bring this all back to total GHG emissions. If we plug these population numbers into our estimate for per capita GHG emissions by income level, we should be in a good position to tally up the total GHG emissions that this implies, under the two scenarios (no growth and growth at the average).ghg-in-atmosphere-to-2050

As you can see, with zero economic growth, the level of emissions is lower, but still really high. (The reason why it stays so high is because, at zero growth, although lower middle income countries like India are not pumping more GHG into the atmosphere, the rich and upper middle income countries still are. Furthermore, while the per capita emissions of the poor stays low, their numbers are increasing at a faster rate.)

For both graphs, the red line indicates the UN’s uppermost threshold (2,310 Gt CO2) for their most extreme emissions scenario. Therefore, the current projections put us on a path of GHG emissions that would mean temperature increases to 2100 of more than 4 degrees Celsius. Once again, well off the charts!

Can technology save our bacon?

It’s entirely possible that sometime next year, “they” will discover cold fusion, a carbon-less, virtually free and infinitely renewable energy source that will allow us to rapidly decarbonise and merrily turn the planet into some kind of Coruscant. I have no clue whether this is a realistic prospect.

But sadly, neither do the people who seem to be depending on it as a solution. And my instincts tell me it is very bad policy to rely on a solution not yet invented in order to solve a problem so grave that it threatens our species’ very existence.

Maybe the way to save our bacon is simply to stop eating it? Lowering our consumption of meat and other carbon intensive goods will surely help. Yet when we look at the scale of the challenge as outlined above, it is clear to me this can only be a part of the solution.

Given that the underlying problem is that there are a lot of people in the world, birth rates are higher than death rates, and most of the world’s poor are getting richer, it seems to me that – absent Cold Fusion – there are really only two other choices:

1) Keep the poor as they are: poor. Stop them from developing economically, so they can’t burn the CO2 which we, the rich folks, have been torching for decades now. Don’t let them have decent houses, clean water or high protein diets, because these things cost carbon, and we haven’t got it to spare. This solution would likely work but it seems to me to be highly immoral. I would hate to live in squalor, be hungry, or to not have healthcare. So I don’t want to espouse policies that depend on others having to live in a way I would not.

2) Move to a Global Single-child policy: The one-woman, one-child policy is the best way there is of controlling these effects. Policies which shift the birth rate equation down at all income levels are the ones most likely to achieve our environmental aims without having to inflict misery and suffering on our own species, or on others. It would take a policy step-shift in thinking to address these problems, but as far as I am concerned, when I look at the numbers, I am certain that this is the only reasonable policy solution there is. We can start by asking religious leaders like Pope Francis to change their messaging around birth control.

And, of course, we can stop thinking of demographic change in the West as a ‘problem’. It isn’t a problem, it’s the start of the only real solution.

NOTE: I am including the full set of data which I used to do all calculations. I welcome any corrections or suggestions for improving the model.

Social Class in Dublin: the final taboo

Dirty old classism
As I prepare to leave Dublin, I find myself reflecting on the things that make life in this city special. Many are splendid: the quick Dublin wit, the pleasant gift of the gab, the unique blend of international culture and local identity. But some are less worthy of celebration, and in this category I would place social class. I have travelled much in my life, and made it my business to understand a place as well as I could, but nowhere have I observed a social class structure quite like Dublin’s. For an issue that barely gets mentioned, class is everywhere on the streets of the Fair City. The fault lines are so visible that you can determine a Dubliner’s social class by their dress style, by their manner of walking, by the very first syllable of the first word that comes out of their mouths; even by the complexion of their skin. Not to mention the neighbourhood they live in: Even the city’s postcodes are euphemisms for the class of its residents.

By way of example: If you’re 25 and you grew up in Clontarf or Clonskeagh (postcodes 3 and 14, respectively), you went to college – probably either UCD or Trinity. If you grew up in Clonsilla or Clondalkin (15 and 22), you did not. The former ‘Clons’ are non-smokers, they support Leinster rugby, go on holidays to the South of France, shop in Dundrum or Powerscourt and work as accountants or barristers; while the latter Clons smoke, support Celtic or Manchester United soccer teams, go on holidays to Spain, shop in Blanchardstown or Liffey Valley and work as builders, shop assistants or else simply draw the dole.

Inequality of opportunity
That wouldn’t be so bad, if it were simply a case of hard work and merit allowing those who earned it to rise a little higher than others. But the truth is, your postcode has little to do with hard work and merit, and much more to do with who your parents were. You need only look at a Dublin child of 10 for a few short seconds and you will be able to project the course of their future prosperity, to a shocking degree. The ones with poor skin, screaming at the top of their lungs in public, and with their feet up on the opposing seat of the Luas Red Line train which they ride late at night without either a ticket or parental supervision, will not command decent salaries in 20 years’ time. The truth is, they have zero chance of advancing up the social hierarchy. Conversely the 10 year olds you meet in the Luas Green Line train, en route from their fee-paying private school in Milltown to their violin lessons in Ranelagh are almost certain to succeed, economically and socially. No matter how lazy they are in school or how badly the bow screeches across the strings, come 2036 they will probably be doing just fine.

Of course, I am deliberately picking extreme cases, in order to make my point. In reality there is a spectrum of privilege and disadvantage. Class is a fluid concept. But the observation is more than just anecdotal. A recent study shows that Ireland stands out among its European peers as having the highest intergenerational persistence of low educational attainment and the highest wage penalty for having a father with low educational attainment. In other words: if your dad didn’t finish secondary school, you won’t either. And you probably won’t earn very much money. This is a bit true everywhere, but it’s especially true in Ireland, and – though I haven’t got data – I’d be willing to bet it’s even more true in Dublin.

Does social class really matter?
I’ve sometimes been accused by those who know me well of over-focusing on this issue. After all, can’t we just let class be class? Some people read The Sun, others read The Guardian. Some people spend their leisure time in betting shops, others in art galleries. If that’s what makes people happy, why is it a big deal?

Unfortunately, class is more than just a preference in culture and clothing. It determines the quality and length of life, not only for yourself, but for your children and their children. The OECD indicator below shows this Class Mortality Gap in brutally stark terms:
class-mortality-gap
While there is a wide variation across countries, what the chart reveals is that being middle class (i.e. you went to college) adds about 4 – 8 years to your life, depending on whether you are a man or a woman. This makes the Class Mortality Gap almost as bad as the Gender Mortality Gap. Having the misfortune to be born to socially disadvantaged parents is almost as bad for your health as being born with a penis.

De bleedin’ elephant in de roo-um
What makes the social class phenomenon in Dublin all the more eerie is the absence of meaningful discussion of it as an issue. The liberal commentariat are hardly silent on women’s rights, traveller’s rights, abortion rights, gay rights and just about any other social issue you can think of. Rightly so, you may well say. But on social class, their silence is deafening. It’s the last taboo subject in polite Irish politics. Worse: There’s a myth of classlessness in Irish society that seems to be perpetuated whenever you bring the subject up. Class, so the narrative often goes, is something that happens in England. And even then, the Irish of rank and privilege are most comfortable with it when it appears in BBC period dramas. Best to keep the Irish Sea and a hundred years of history between ourselves and the whole messy business!

Riot at the Fringefest in Merrion Square: The excellent rapper Emmet Kirwan sells working class culture to middle class punters at prices only their accents can afford.
Riot at the Fringefest in Merrion Square: The excellent rapper Emmet Kirwan sells working class culture to middle class punters at prices people with his accent could never afford.

Myself and my equally middle class partner recently went to see a show at a pop-up theatre in one of Dublin’s more middle class gated parks: Merrion Square. In the queue for pre-show food (wraps, don’t you know – one had one’s choice between halloumi and falafel) we conversed politely with our fellow show-goers, using rounded vowels and fully enunciated consonants. Then it was time to filter in to our seats. The show was called “Riot”, an eclectic mix of acrobatics, music and political commentary, featuring Ireland’s most famous drag queen, Panti, who since the Marriage Equality Referendum last year has become something of a national treasure. The politics played very much to the crowd. In between slapstick gymnastic routines and sing-songs, there were frequent called to “Abolish the 8th”, a reference to Ireland’s constitutional prohibition on abortion-on-demand.

But the showstopper was a young artist named Emmet Kirwan. He hails from a working class Dublin area known as Tallaght – a suburb built in the 1970s and 1980s to cope with the overflow from crowded inner city neighbourhoods. Kirwan’s unique blend of the Dublin working class vernacular and hip hop was as electrifying as anything I had seen on stage. With such an overtly political tone to the production, his indisputable talent and the obvious power of the medium to convey just such a message, this was surely the perfect opportunity for Kirwan to cast some home truths into the sea of class privilege upon which he gazed. I was waiting for the lyric: “A boy of three / undernourished and weak / Can’t afford to eat / Cause his ma’ don’t take home in a week / what youz are after spendin’ to sit in dah’ fuckin’ seat”

That lyric never came. Kirwan was happy to bang on about poverty, but he kept the teeth of social disadvantage well away from the manicured hands that were feeding him. The audience took it all in politely, letting out a dutiful cheer whenever the politics of the left-leaning middle class were voiced (pro-choice, anti-Catholic church) But nowhere was there an honest recognition of the dissonance between the culture on the stage which they were happy to expropriate, and the social reality of that culture’s roots, which they and their parents not only avoided at all costs, but in fact were the ultimate authors of.

Choose your parents carefully
If class is so present, such a problem, and yet Dubliners are so unwilling to talk about it, can anything be done? Is there anything more concrete we can offer to young people who’ve already made the mistake of not selecting rich parents before they were born? Or is it just too late? I, for one, think there’s quite a lot that could be done. We could start by looking at how (and in which neighbourhoods) social housing quotas are being filled; taking a hard and honest look at how the State is subsidising fee-paying private schools; looking at thresholds for inheritance and gift tax.

But before we get to concrete policies, the discussion has to start by acknowledging de bleedin’ elephant in de roo-um. Here’s my lyrical contribution:

Dublin is a class-riven city,
And the cost of that is shitty.
We bury are heads in de sand
Makin’ like it was all grand.
Wha’ a bleedin’ pity!

The Hillary Fallacy – why the “Kang and Kodos” logic does not appeal to me.

two party system

 

 

 

 

 

 

Despite my better judgement, I have recently found myself getting into social media exchanges with supporters of Hillary Clinton’s presidential bid. These exchanges are often acrimonious and always pointless, because no one ever manages to convince anyone else of their point of view on social media. However, the arguments propounded provide some interesting insights into where this campaign has taken us.

When I express my preference for a third party candidate, Hillary supporters usually begin – not by extolling their candidate’s merits (even they realise this is a claim too far) – but by using the now familiar argument that a vote for Jill Stein or Gary Johnson is a de facto vote for Donald Trump. This argument is of course nothing new. Years ago it was derided in a Simpsons episode in which Bob Dole and Bill Clinton are revealed by Homer to be nothing more than the hideous space aliens Kang and Kodos, bent on enslaving humanity. When a member of the crowd then threatens to vote for a third party candidate, the aliens mock him. “Go ahead, throw your vote away.”

Back to the Social Media exchanges: I usually respond to the Kang and Kodos argument by explaining that although I think Trump is a thoroughly repugnant individual and an awful candidate, at least he won his party’s nomination through a fair and open process, and he did so against the wishes of the party elites. The same, I point out, cannot be said for Clinton; certainly not after the latest Wikileaks revelations. I then note that I believe the price America would pay (i.e. a Trump presidency) in order to punish the DNC for rigging the nomination would possibly be worth it, if the sting to the DNC was so great that it delivered real electoral reform for the next primary process. After all, what is at stake is something greater than 4 years of stupidity. It is the essence of democracy in the United States.

What follows from Hillary supporters is a strange defence of the democratic nomination process being rigged. They often say something like, “Well, the process isn’t intended to be fair.” or “Parties can do what they like. They don’t even have to involve the electorate if they don’t want.” or else even “There’s nothing in the Constitution about how the DNC must organise its nomination process.”

This is of course perfectly true. Except when you combine the two arguments, “the DNC can rig all it likes and choose whomever it pleases” + “a vote which is not for the DNC’s chosen elitist is a vote for the other monster on the podium!” you essentially have an admission that the choice of president is in no way democratic. If the party nomination processes offer no real choice, then the two-party general election certainly doesn’t either.

So if the Constitution does not provide guidance on the fair administration of primary contests, perhaps it is time for Constitutional reform. After all, the current system is so badly broken that even the most ardent supporters of the candidate whom bookies say is going to win in November (let’s call her “Kodos”) can only invoke the Kang and Kodos defence to convince us to vote for her.

In the meantime, I will be using my vote in November to punish Debbie Wasserman Schulz and the DNC for what they have done to Bernie Sanders’ Political Revolution. I will be voting for Jill Stein, and I’ll be encouraging red state voters to choose Gary Johnson.