Australia isn’t doing its part for the global climate …

… Sooner or later we’ll have to pay our share. That’s the headline for my latest piece in The Guardian. The more important message is in the “standfirst” text that runs before the article proper.

The cost of responding to climate change is trivial compared with the benefits

To spell this out, here are the concluding paras of the article

The good news is that the cost of an emergency response, while large compared with an efficient policy, will be very small in relation to an economy with an annual output, by 2030, of $2tn a year or more. To see this, we can turn to the estimates prepared for the government’s election campaign by Brian Fisher of BAEconomics.

These worst-case numbers, higher than the costs of the most radical emergency measures, amount to around $50bn a year, or 2.5% to 3% of national income. That’s a lot of money – like adding a new program on the scale of the NBN or the submarine contract every year for five to 10 years.

At the same time, it’s small enough that it would barely be noticed against the background of the general fluctuations in the economy. The average household has lost far more from the wage stagnation of the last decade. As far as the government budget is concerned, the likely impact is comparable to that of increasing health expenditures arising from our increased life expectancy and the development of new treatments.

More importantly, the cost of an emergency response to climate change is trivial compared with the benefits of stabilising the global climate at a level that is livable for humans and the natural environment. We are currently shirking our contribution to this global public good, and free riding on the efforts of others. But sooner or later we will have to pay our share.

Why “extremely unlikely” climate events matter

I’ve just been advised that my latest article “The importance of ‘extremely unlikely’ events: Tail risk and the costs of climate change” has come out online in The Australian Journal of Agricultural and Resource Economics. For those who can use it, the DOI is 10.1111/1467-8489.12238. For everyone else, here’s a link to a pre-publication version. The main points are

* The IPCC convention is to use the phrase “extremely unlikely” to refer to outcomes (in particular, values of climate sensitivity) in the range of 0–5 per cent.
* Most of the risks against which we act to protect and insure ourselves (for example, car crashes, premature death in any given year) are “extremely unlikely” by this definition
* Around half, or even more, of the expected welfare loss from climate change arises from the worst-case 5 per cent of high values for climate sensitivity.

Nothing really startling here, but it’s the other side of the coin to the contrarian suggestion that since there’s a 5 per cent probability that global warming will turn out not to be a problem, we should do nothing.

Copenhagen commitments

While Australia has been transfixed by the meltdown of the Liberal party, there have been a string of positive developments around the world, which make a positive outcome from Copenhagen, leading over the next year to an intermational agreement to limit greenhouse gas emissions, much more likely than it seemed two years ago, or even six months ago. Among the most important developments

* Obama’s commitment to a 17 per cent (rel 2005) target, which essentially puts the Administration’s credibility behind Waxman-Markey
* China’s acceptance of a quantitative emissions target, based on emissions/GDP ratios, but implying a substantial cut relative to business as usual
* The change of government in Japan, from do-little LDP to activist DPJ
* EU consensus on the need for stronger action
* Acceptance of the principle of compensation for developing countries, and acceptance by countries like India that they should take part in a global agreement and argue for compensation
Read More »


The Great Ute Scandal has been bubbling along for weeks but I ignored it, partly because scandals are rarely interesting and partly because I couldn’t get to the starting point of working out what wrongdoing was supposed to have taken place (compare for example the Manildra business, which involved large sums of public money and provoked no serious concern). But in the last day or two the stakes have been raised dramatically, based on the alleged email from the PM’s office urging a prompt response to the concerns of a car dealer who contributed a car to Rudd’s campaign.

Whatever the significance of the putative email may have been, Rudd’s outright denial that any such email was sent means that it will be a major crisis for him if the email turns up, and possibly a terminal one if it turns out that the email was suppressed. On the other hand, if it can be proved that the email published by the Telegraph and referred to by Turnbull was in fact a fake, the consequences will be dire for Turnbull at least (I don’t suppose the Tele could lose much credibility). As my recent spam crisis demonstrates, I’m no tech expert, but I would have thought that the headers on an email would make it pretty easy to check whether it had been sent and that erasing all trace of an email would be just about impossible. And it would be grossly irresponsible to publish an alleged email if you received it with the identifying info removed.


The news that the email was a fake confirms that the outcome will be bad for Turnbull, and could be catastrophic. The worst case, but a plausible one on the evidence to hand, is that the email was the product of a fraud cooked up between Liberal staffers and one or more corrupt Treasury officials. Even the best case, that the email was fabricated for some personal reason, and passed to the Liberals along with other leaks about the car scheme, doesn’t look good. I guess, given the twists and turns so far, it’s also necessary to consider the Machiavellian possible of a (highly successful) agent provocateur, luring Turnbull into a trap, as happened (IIRC) with Ralph Willis in 1996.

Further update

It now appears that the worst-case scenario is pretty close to the truth. Grech has apparently been working as a source of leaks to the Liberal party for a long period*. Apart from the obvious disastrous implications for the Liberals, this point also casts doubt on what remains of the case against Swan. If Grech was working for the Libs all along, he could easily have generated a large volume of emails, reports and so on, without any particular pressure from the government

* The term “mole” is commonly used in such cases, but the original idea of a mole was one of an agent in place who did nothing but burrow nto the target organisation, waiting for the time to act.

Garnaut draft report released

The Garnaut Review draft report has just come out. The site is clogged, but I’ve managed to get a copy of the report and press release (I’ve attached the latter here.

There’s a lot of discussion of the Murray Darling Basin where the worst-case projections are about as grim as they can possibly be. My UQ research group (Risk and Sustainable Management Group) did the economic modelling that translated the climatic projections into predicted changes in land and water use. There are big adverse impacts under most of the ‘business as usual’ scenarios. On the other hand, in the projections where CO2 concentrations are held to 450 ppm things aren’t bad, and even 550 ppm would still allow irrigation to continue.

More soon on the policy recommendations. Whether or not the government ultimately follows Garnaut’s proposed model, there’s no doubt that the Review has shifted the terms of debate substantially. Those (like the Federal Opposition) who are tempted to play the issue for short-term political gain will pay a big price in the end if they succumb to that temptation.

Looking back at the Club of Rome

A point discussed on the blog recently is whether Limits to Growth actually predicted rapid exhaustion of critical natural resources, or whether this was a misrepresentation by much later critics. The text itself isn’t definitive, since it contains some projections showing rapid exhaustion and others (in which discoveries boost stocks by a factor of five) in which exhaustion takes place over a century or so, and also because the projections were revised in later editions. However, my memory is that both supporters and critics focused on the more extreme projections.

I have a couple of pieces of evidence to support this claim. First, I’ve put over the fold a piece by Matthew Simmons defending the Club of Rome and saying

Nowhere in the book was there any mention about running out of anything by 2000. Instead the book’s concern was entirely focused on what the world might look like 100 years later.

But Simmons’ case is undermined by the dust jacket at the beginning of his article which sells the book as ‘The headline-making report on the imminent global disaster facing humanity’. I think most readers buying a book that was sold like this would focus on the worst-case scenarios.

To support this interpretation, here’s a para from a 1979 book, Economics, environmental policy and the quality of life, by Baumol and Oates who begin their Chapter 7 with a reference to Limits to Growth

Certain recent studies have raised the spectre of complete exhaustion of some of the worlds critical resources. they tell us that in the absence of drastic countermeasures, within a matter of decades mankind is likely to run out of petroleum, natural gas and other vital fuels, to deplete virtually all the sources of various minerals such as mercury, copper and silver and to have cultivated essentially all remaining and still usable land. In brief, the world economy will be brought to the brink of catastrophe by hte exhaustion of natural resources.

Baumol and Oates also present in Chapter 9 a “Standard Run” from the World Model showing catastrophic collapse a little over halfway between 1900 and 2100, that is, right about now. Baumol and Oates, like most economists, are critical of Limits to Growth, but they aren’t rightwing anti-environmentalists by any stretch of the imagination. I think it’s fair to say that most readers at the time, whether they agreed with the Club of Rome or not, focused on predictions of imminent resource exhaustion, and not on what might happen in 2070

Read More »

Less bad news from Iraq

Over the last few months, the volume of bad news from Iraq has diminished. For example, the number of US troops killed in November (about one per day) was the lowest in a couple of years. While it’s much harder to measure Iraqi casualties the number seems to be declining, at least in Baghdad. What does this mean for the policy choices facing the US and its allies?

The short answer is ‘Not much’

Read More »

How much does it cost to save the planet?

There’s been quite a bit of discussion here and elsewhere about the cost of large (60 per cent or more) reductions in CO2 emissions. A lot of people are intuitively convinced that since everything we do uses energy, large reductions in energy use can only be achieved at the cost of large reductions in living standards. Economic analysis says the opposite. Typical estimates of the cost of such reductions are in the range 1-3 per cent of income for the world as a whole. Australia is more energy intensive, and ABARE (by no means biased low on this kind of thing) gives a range from 1.7 to 3.4 per cent for plausible scenarios. Only by rigging the game could ABARE get the high estimate of 10 per cent, quoted by Howard a while back. And even a 10 per cent reduction in income, by 2050, would not actually be noticeable against the background noise of macroeconomic and individual income fluctuations. On plausible projections, it would mean average income would increase by 110 per cent instead of 120 per cent.

Read More »

The Stern Review and the long tail

My first post on the Stern review started with the observation that

the apocalyptic numbers that have dominated early reporting represent the worst-case outcomes for 2100 under business-as-usual policies.

Unfortunately, a lot of responses to the review have been characterized by a failure to understand this point correctly. On the one hand, quite a lot of the popular response has reflected an assumption that these worst-case outcomes are certain (at least in the absence of radical changes in lifestyles and the economy) and that they are going to happen Real Soon Now. On the other hand, quite a few critics of the Review have argued that, since these are low-probability worst cases, we should ignore them.*

But with nonlinear (more precisely strongly convex) damage functions, low-probability events can make a big difference to benefit-cost calculation. Suppose as an illustration that, under BAU there is a 5 per cent probability of outcomes with damage equal to 20 per cent of GDP or more, and that with stabilisation of CO2 emissions this probability falls to zero. Then this component of the probability distribution gives a lower bound for the benefits of stabilisation of at least 1 per cent of GDP (more when risk aversion is taken into account). That exceeds Stern’s cost estimates, without even looking at the other 95 per cent of the distribution.

An important implication is that any reasoning based on picking a most likely projection and ignoring uncertainty around that prediction is likely to be badly wrong, and to understate the likely costs of climate change. Since the distributions are intractable the best approach, adopted by the Stern review, is to take an average over a large number of randomly generated draws from the distribution (this is called the Monte Carlo approach).

To sum up, the suggestion that because bad outcomes are improbable, we should ignore them is wrong. If it were right, insurance companies would be out of business (not coincidentally, insurance companies were the first sector of big business to get behind Kyoto and other climate change initiatives)
Read More »