Saturday, February 23, 2008

Julian Simon, the limits to growth and infinite resources

The Earth's physical resources are finite. We threaten our future if we try to live beyond those means, so we must build a sustainable society that guarantees our long-term future.
The above quotation comes from a document describing the philosophical basis of the Green Party. The late economist, Professor Julian Simon, rejected this view in his book, The Ultimate Resource 2. To quote from Chapter 3 (entitled "Can the supply of natural resources - especially energy - really be infinite? Yes!"):
Chapter 2 showed that natural resources, properly defined, cannot be measured. Here I draw the logical conclusion: Natural resources are not finite. Yes, you read correctly.
So here we have a deceased but influential economist claiming that resources are infinite! Note the "properly defined" bit above. The following paragraph from the summary of Chapter2, illustrates the thinking here:
Material-technical forecasts of resource exhaustion often go wrong for two reasons. (1) No matter how closely defined, the physical quantity of a resource in the earth is not known at any time, because resources are sought and found only as they are needed; an example is the increase in the known supplies of such resources as copper, as shown in table 2-1 and figure 2-1. (2) Even if the physical quantities of particular closely defined natural resources were known, such measurements would not be economically meaningful, because we have the capacity to develop additional ways to meet our needs - for example, by using fiber optics instead of copper wiring, by developing new ways to exploit low grades of copper ore previously thought not usable, and by developing new energy sources such as nuclear power to help produce copper, perhaps by extracting it from sea water. Thus the existing "inventory" of natural resources is operationally misleading; physical measurements do not define what we will be able to use as future supplies.
What Simon has demonstrated is that it is hard to measure what resources are available in the earth, that we don't know what future means of providing those resources or substituting for them will become available and it is thus hard to define what resources the earth can/will ultimately provide to humanity.

However he has not demonstrated that the earth can provide us with "infinite" resources, merely that we do not know what resources it could ultimately provide us with. However Chapter 3 is where he attempts to demonstrate that resources are in fact "infinite". I shall tackle the reasoning there in my next article.

One might ask why I am bothering with this. The answer is that, whilst Simon is wrong about getting "infinite" resources from the earth, he has sound arguments to make about the economics of resource usage/scarcity and I believe he goes wrong in an "interesting" way. Understanding where he goes wrong can help understand what the real situation is regarding "the limits to growth".

Thursday, February 21, 2008

Blog topics

I'm currently adding labels to old posts produced before labels were added to

The result so far is an increased list of topics in the "Topics" side bar (this used to be labelled "Labels"), plus an increased number of articles indexed by the labels. My aim is to get rid of the (renamed) "Google Searches" side bar that I used a substitute for labels. I won't necessarily catch all articles, but hopefully it will make it easier for readers to look up the material that interests them in this blog.

Wednesday, February 20, 2008

The Commoner-Erhlich Equation

Further to my previous article, on the report from the Optimum Population Trust, I've been doing a bit of digging around on the I=PAT equation. Remember here that I is the measure of the impact of humanity on the environment and P is the population and A is a measure of affluence (or consumption). The question is what is T measuring? The OPT reports talks about T somehow measuring "technology".

Anyway according to Wikipedia, T is in fact humanity's ecological impact per unit of consumption. A is measured as consumption per capita. So by multiplying the population P by the consumption per capita A, you get total consumption, after which you multiply by T the total impact per unit consumption to get I, the total environmental impact of the population and its level of consumption.

Given this, it is clear Tim Worstall's criticism of the I=PAT equation, saying that we should divide by T, not multiply by it, is mis-placed. Mr Worstall is treating T as if it measures technological sophistication. I agree with him that technological advancement reduces our environmental impact, at least for a given standard of living and population size, but that is not what T is measuring here. Technological advancement allows us to e.g. use less energy and resources and/or reduce pollution per unit of consumption. Thus such advancement reduces the value of T. The question then is whether the equation is an adequate description of what's going on. It assumes independence of its variables and it also assumes the variables can be measured reasonably accurately. It seems to me both assumptions are questionable.

For example, there may be feedback loops between the variables that aren't catered for and it's not entirely clear how one would measure either "consumption" or "environmental impact" in a clear, accurate manner.

Technology, Affluence and the Optimum Population Trust

The Optimum Population Trust recently published a study which claims that Britain's optimal population is about 17 million people:

If the UK had to provide for itself from its own resources, it could support a population of only 17 million – 43 million less than its latest official population figure* - according to new research by the Optimum Population Trust.

Even if the UK dramatically improved its sustainability with a 60 per cent cut in carbon emissions by 2050 - the target set by the present Government - UK “overpopulation” would grow from 43 to 50 million, the research shows. This is because projected population growth of 17 million**, taking the country’s population to 77 million by 2050, would cancel out the sustainability benefits of carbon savings.

The sustainability of human populations: How many people can live on Earth? ***, published today (Monday February 18), is based on a new analysis of biological capacity and ecological footprinting data. It suggests that in 2003, the last year for which comprehensive data are available, total world population was 6.3 billion but the sustainable figure was 5.1 billion. Global overpopulation was thus 1.2 billion. (italics in original)

A 9-page report based on this study can be downloaded here. From pages 2 to 3:
Not surprisingly, the impact of this population growth on the environment since 1750 has been extensive. Now, not a day goes by without news of droughts, floods, famines, conflicts over resources, extinctions, and, in the last 20 years, the increasingly evident effects of global warming. This impact has been expressed in what has become known as the Commoner-Ehrlich Equation:

I = P x A x T.

This states that the impact (I) on the environment is directly proportional to the population size (P), the ‘affluence’ (A) (defined as the resources a population consumes and wastes) and technology (T) through which we (1) prolong life, (2) produce things more quickly and cheaply (thus feeding back into consumerism and affluence) and (3) grow food faster which feeds back into ‘population’. This equation thus neatly summarises the impact of humankind on the planet.
Note that it is assumed that technology is multiplicative factor that increases the human impact on the environment. Yet technology mitigates the impact we have on the environment by enabling more efficient use of resources and/or less polluting methods to be used.

It is technology that has enabled us to sustain the large population we currently have on earth, living longer and healthier than at any time in history. Remove the technology and the environment would be devastated as people desparately try to grow food and obtain water using methods that simply cannot sustain us. Indeed, based on similar points to mine above, Tim Worstall argues that we should divide by T rather than multiply. However reading further, it seems that T isn't measuring technological advancement, but rather the impact of technology on the environment:
Politicians, unsure what to do, offer solutions which include suggestions such as: develop fuel-efficient cars; change to efficient light bulbs; fly less; build renewable energy and nuclear power plant; increase mass transit systems; and plant trees. These solutions only address the reduction of the affluence and technology variables of the equation, but never the population variable.

Reducing impact by decreasing affluence (consumption) only partly addresses the problem since populations are growing faster than affluence – for example, in Africa. Technology, meanwhile, tends not to “decrease” at all. Whilst it can be used to reduce the impact of affluence, it is likely that its benefits in energy saving devices will be cancelled out by its disadvantages, as businesses continue to use it to maximise their economic growth via consumerism. So, realistically, impact will continue to rise since economic growth demands it. This is bad news since, as we will now see, human impact on the planet is already unsustainable. (italics in original)
Here the paper acknowledges that technology can in fact reduce the impact of humanity on the environment (though it argues that the drive to economic growth will then cancel this out). To retain T as a multiplicative variable, whilst acknowledging that it can reduce humanity's impact on the environment, one must consider it to be a measure of the impact of our technologies on the environment, rather than a measure of advancement. Technological advancement will thus tend to reduce T, and I'd suggest it has been doing so for centuries whilst increasing population and affluence have offset the reductions in impact it enabled.

An interesting point is that there is no mention in this study of one of the main findings in demography which is that increasing affluence has lead to a fall in birth rates resulting in slow population growth rates or even declining populations in rich countries. This implies that rising affluence may in fact help with the goal of slowing population growth, a finding that is at odds with the arguments presented on the OPT's paper.

I intend to return to other aspects of this paper in later posts.

Thursday, February 07, 2008

Yusuf Al-Qaradawi and freedom of speech

Inayat Bunglawala, writing in the Guardian, claims that the British government's refusal to give Yusuf Al-Qaradawi a visa, thus refusing permission to enter the country, violates Qaradawi's freedom of speech:

Gordon Brown's government has finally caved in to the noisy mob who have been angrily demanding that the elderly Islamic preacher, Yusuf al-Qaradawi, should be refused a visa to come to the UK for medical treatment.

Well, so much for free speech. You will recall that during the Satanic Verses and the Danish Cartoons row, British Muslims were repeatedly lectured to about the need to adapt to western notions of free speech. You may not like what is written or drawn, we were told, but as long as it does not break the law, you need to learn to put up with it.

The problem with this argument is that Mr Qaradawi's freedom of speech has not in fact been curtailed. His words have not been banned from the media or the internet, he can continue giving interviews, making speeches, etc. It's just he's been refused permission to enter the country, which is no more of a violation of his freedom of speech than if I were to refuse him entry to my house.

The point is that freedom of speech is the right to express your views with your own resources, or resources you otherwise have permission to use, to anyone willing to listen. Freedom of speech does not give me the right to enter your house without your permission. Similarly it does not give a non-citizen the right to enter a country, whether he wishes to do so in order to spread his views or simply to have a holiday. The non-citizen must get permission from the country's government to do so (said government exercising this power on behalf of the people of that country).

In practice permission is often granted by default, assuming you apply/arrive through legal channels. But governments have always had the power to refuse permission, a power which the are supposed to exercise in defence of the country concerned (e.g. to repel foreign invaders or anyone else who poses a risk to that country's population). In this case, the British government has decided Al-Qaradawi poses some sort of threat. Whether they are right in that decision is a separate matter from any alleged violation of freedom of speech.

Mr. Bunglawala is confusing freedom of speech with the right to be provided with a platform of one's choice in a location of one's choice. No one has that right.