Saturday, March 27, 2010

Why are so many climate scientists Neo-Malthusians?

Ever since Ehrlich's Population Bomb and the Club of Rome reports, there is concern about the size of human population on Earth. Following the observation of Malthus that there were more births than funerals in his parish, 20th century thinkers have warned about the limits of the carrying capacity of Nature. More people means more problems. In a climate change context it seems obvious that more people mean more GHG emissions. However, this simple thought neglects the fact that it is relative wealth of a given population which impacts on emissions. 300 million in developing countries are not the same as in the energy hungry North.

I quote from an insightful article (copied from another thread, we have been here before...
Paul Wapner and John Willoughby (2006) ‘The irony of environmentalism: the ecological futility and economic necessity of lifestyle change’, Ethics and International Affairs, 19(3): 77-89):

"Many environmentalists call for reducing family size and consuming less because they see these as ways to decrease the total amount of spending within an economy. Reduced spending limits the demand for resources and the production of waste, and thus contributes to environmental wellbeing. As we will demonstrate, however, while less spending within an economy may, in fact, minimize environmental harm, it is not the case that cutting back on individual consumption or having a smaller family will reduce overall spending. In most cases, such actions will simply shift the locus of spending. If a family, for example, continues to receive the same amount of income but decides to buy fewer products or have fewer children (and thus forgo the consumption associated with additional family members), they have more savings at their disposal. In fact, much of the literature advocating less consumption and greater consumer simplicity emphasizes the bonus of extra savings. It is crucial to recognize, however, that savings do not simply sit in banks or other financial portfolios; rather, they are deployed by financial institutions to fund investment projects. Consequently, because purchasing power is fungible, it makes little difference ecologically if one saves or invests money rather than spends it. For, aside from placing money under one’s mattress, it will most likely be used by investors to create more economic wealth, and this will be done primarily by funding practices that use resources and create waste."


Rob Maris said...

It looks like two things are a bit mixed here. Separated:
1. Wapner and Willoughby surely meant a situation where population has a certain (constant) figure and part of this population decides to reduce their consume. BTW: very interesting to notify their ideas about shifting and to get aware about it.
2. The overall load on our environment is surely heavily dependent on population (or, more precise: population and production/person). So I think it is fully plausible wenn many climate scientists are "Neo-Malthusians.

Tobias W said...

Why are so many climate scientists neo-Malthusians?

I think the answer is quite simple; because many climate scientists - like old Uncle Scrooge himself - simply doesn't like people. Most of them seem to be environmentalists (certainly the Hockey team and the CRU-bunchs association with Greenpeace et al is shown in the Climategate-letters, and makes them look more like activists than scientists), and as such sees humans as the destroyers of "pure" mother nature.

As Malthusianists have always been wrong and always will be wrong, it doesn't surpise me that many climate scientists holds these dystopic beliefs. Somehow it seems represented in their work...

J. Zimmermann said...

I don't see any evidence that climate scientists, whoever this term relates to, are indeed "Neo-Malthusians". Usually climate science deals with forcings, not with population. In the short run indeed a minority on earth makes the climate problem by its excessive life-style. In the long run it is population that matters, if nobody wants to advocate that we artificially keep a large part of the global population poor. So it looks like a distraction. Either we find a life-style that is sustainable when adopted by everyone or we are running into costly problems no matter how long it takes until everyone on earth can claim the western life-style.

Duke said...

As to the economics and savings, I agree that for one generation it might not make much difference in per capita consumption and ecological impact, but the next generation will be of the same size or smaller, and that will help keep the total ecological impact manageable.

Anonymous said...

A couple points here:

1. This post conflates climate scientists with environmentalists, which is a common mistake I see repeated in many venues featuring the great climate debate. There may be substantial overlap between the two groups, but they are not the same thing.

2. It is not entirely clear that more people mean more GHG emissions. With current technologies, yes, but not necessarily with new and different energy production technologies.

3. Ehrlichian/Malthusian ideas are widely derided because of Ehrlich's famous incorrect prediction. However, statements such as that of Tobias W ("As Malthusianists have always been wrong and always will be wrong...") also seem misguided and born of a certainty that I would suggest merits some introspection. Just because Ehrlich got the time period wrong does not mean that there are not limits to the level of resource use the planet can sustain. Absent substantial innovation, Ehrlich could well be proven right in the coming century.

I myself am agnostic about that. We have substantial capability to innovate and overcome resource limitations, and this innovation might cause such worries to be unfounded. However, there might well be an asymptote to our ability to innovate our way out of resource limitations. And, on the way to that asymptote, we could well find ourselves living on a planet (or even on other planets) that bears little resemblance to the one we currently live on, one that is instead entirely given over to serving human direct consumption needs.

Thanks, M

Werner Krauss said...

I tried my best, but I don't get the Wapner / Willoughby quote. What is wrong in not buying energy-intensive crap? And where do they know from that the saved money is not invested in alternative energies? And what is their interest in judging other people's lifestyle decisions?

AnonyMoose said...

300 million who are cooking with burning dung have a different effect upon the environment than 300 million who are powered by nuclear fission.

Unknown said...

What Wapner and Willoughby don't get is the simple correlation between wealth and environment: As soon as people have enough to eat and a safe place where to live, they start worrying about the environment they live in. More wealth creates hence a better environment by freeing up the capacity to deal with environmental issues. It is poverty that is the single most damaging factor to forests, soils, groundwate, rivers and the air.

There are many empirical examples to prove this correlation and only one counter-example: If one believes that CO2 harms the environment, there are currently no mechanisms in place to price the hypothetical damage to the climate. It is there, where more wealth will transiently create more emissions until the time that renewables have catched up in cost efficiency.

Tobias W said...


Hear, hear!


Malthusian ideas about finite resources, population rises and their impacts on society have been around for nearly 2000 years. They have all been wrong up to this point. To me that suggests they have no idea of what the drivers of human civilisation actually are and how they perform. To you it suggests that it just hasn't happened yet. I can't invalidate that statement, but as it's correlation with reality has beeen zero - I would think it highly unlikely that their dystopian predictions will ever come true!

Zajko said...

Bjorn said: "More wealth creates hence a better environment by freeing up the capacity to deal with environmental issues. It is poverty that is the single most damaging factor to forests, soils, groundwate, rivers and the air."

This is a good point, but it is only true up to an extent - I think the relationship depends on a number of other factors. First, there are numerous cultures with little wealth (what could technically be defined as poverty) that have historically had low environmental impact. Granted the idea that "primitive" cultures all lived in harmony with their environment is a myth, but the correlation between wealth and environmental exploitation is not straightforward. I would say the market incentives for environmental destruction are more important than poverty. Also, wealthy countries vary in their approach to the environment, and while they can certainly afford such "luxuries" as national parks, this still requires a value judgment. For example, the discourse in the US and Canada has frequently stated that the environment cannot come at the cost of the economy, and as an economy currently dependent on natural resource extraction we here in Canada are not about to stop carving up our landscape just because we're wealthy. Rather, we are able to do so on an even-greater scale (although with the luxury of "impact assessments" and the like).

As for overpopulation: I see it as pretty plain that this it can be considered a serious problem, and given the way a certain society is set up there are certainly limits to growth - but this does tend to mask some of the other relevant issues that have already been brought up, and enters into a moral minefield. I wouldn't call it a "root" problem, but it can compound others.

A couple of other points of view:

Population: The elephant in the room

Overpopulation: Maybe we actually need more people? (this one is short on details)

Unknown said...


For all practical purposes, we can neglect the few stone-age cultures that still survive in this discussion. For the environment, there is certainly a U shape on the wealth axis but we can consider all economies as emerging markets that have surpassed the initial environmental decline.

The primacy of the economy over the environment in the US and Canada is not really a counter-example: Compare the Canadian environment with that in Burma or Bangladesh. It is not only the "luxury" national parks that count. It is basic pollution protection in cars, every-day waste management and product safety for toys and in-house colours, to name a few, that add to life quality in richer countries.

And overpopulation is very relative. 100 years ago, 7 billion people on Earth would have been impossible to feed. The nice thing with human ingenuity is that it keeps pace with the biggest challenges. In 2050, 9 billion people will be 'easily' fed at a comfortable level. You take my bet?

Zajko said...

To say that overpopulation is relative does nothing to dispute it as a real concern, it just focuses our attention on the ways in which capacity varies. I don't think 9 billion people is at all an unreasonable number for the future, but this would assume certain things about land use, agricultural practices and climate, none of which I feel confident enough to bet on. Finally, up until today the ability of people to be fed has not been limited by (global) supply. This may change in the future, but I'm willing to bet that hunger will continue to be caused by factors other than a global food shortage for a long time to come (if ever).

Going back to wealth and the environment: Using certain metrics it is easy to argue that many things have improved through development, namely as you state - regulations affecting quality of life. But as long as the market favors certain forms of environmental exploitation, an increase in wealth will not limit such economic activity but actually intensify it. Wealthy countries certainly seem better able to regulate such behavior, but whether they actually do or not is very conditional. Particularly where environmental impacts do not threaten a population's quality of life, or where these costs are hidden, it seems government regulation is typically willing to step aside and let industry profit (again I'm using Canada as my main example, since that's what I'm familiar with). Even in cases where the costs seem pretty obvious (I'm thinking overfishing) it seems regulation is often unable to challenge increasingly sophisticated and large-scale industrial activity. Using the metrics of land area (and ocean) altered by human development, I think I could give you a nice correlation based on some cases where increased wealth = greater environmental destruction.

Anonymous said...

Coming back to Malthusianism, I think it is an unjustifiably robust claim to suggest that the past 2000 years have disproven the concept of finity in natural resources. It really depends on what scale you look at the issue. True, there has never been a worldwide human population collapse caused by over-exploitation of natural resources, but one can point to many examples of resources at local or regional scales being depleted and leading to societal hardship or even collapse. Look at the cod fishery of Newfoundland as one local example.

Also, there have never before been 6+ billion people on the planet before. A global calamity may never happen, a la Malthus, but I would say that there is a rising chance that there will be an increasing number of local to regional scale resource depletions as our population hits 9 bn, that will, in aggregate, cause large socio-political and economic problems.

Addressing Bjorn's point about more wealth=better environment. Sure, if you are only looking at the wealthy society's immediate environment. It is true that America and Europe have more forest and cleaner air than 50-100 years ago. But our cleaner and greener backyards come at the expense of large environmental impacts shifted elsewhere (the greater amount of resources we consume must come from somewhere). Let's forget carbon for the moment, and think of the direct impacts of our appetites, which lead to the clearing of forest and cerrado in Brazil for soybean production, extensive salmon farming in Chilean fjords, clearing of mangroves for prawn aquaculture in many tropical coastal countries, just to name a few. The 20+ kg of catalogs that each American receives annually comes from pulp supplied in part by boreal forest clearcuts, as does much of our toilet paper. And of course there is China's dirty air and water, which is directly related to all the manufacturing of low cost goods that go to satisfy wealthy markets.

Wealth does indeed lead to local greenery, but arguably results in greater, albeit more diffuse, environmental impacts.

Best, M.

Unknown said...

Mazibuko: I believe that Zajko and me are actually discussing Malthusianism, i.e. the question, whether the environment is deteriorating to such a level that Nautre is not able to feed humankind.

I acknowledge and know both your counter-examples to my thesis that more wealth is good for the environment. However, I believe that these display transitional effects and suggest us looking at the environmental impact of wealth on the long run.

Over the long run, "we" (in the industrialized countries in the Western hemisphere)
+ are abolishing child labour even in China and other poor and emerging market;
+ are setting production standards even for imports in terms of the materials used, there source and production processes;
+ are supporting water and air pollution in emerging markets (we export them and can make money from clean tech);
+ are over time getting better and better informed about pollution in remote areas and use our consumer power to solicit environmental-friendly corporate governance.

On the other side, we dramatically fail to solve trans-national environmental issues such as over-fishing, so I take your point there. The truth is probably in the middle, as always.

@ReinerGrundmann said...

"Over the long run, "we" (in the industrialized countries in the Western hemisphere)
+ are ...
+ are ..."

-- this says it all

" ...abolishing child labour even in China and other poor and emerging market;
Do you know what child labour on the country side looks like?

+ are setting production standards even for imports in terms of the materials used, there source and production processes;

so you are happy to deny them 'the right to development' as long as we can continue with our lifestyle?

+ are over time getting better and better informed about pollution in remote areas and use our consumer power to solicit environmental-friendly corporate governance.

--in order to keep the cheaply produced stuff out of our pleasant Western countries??

Sorry to bother you with these direct questions.