by Patrick Appel
A reader responds to Manzi's post on his blog. A snippet:
I think Manzi is using his quantitative skills to pound a screw.
For one thing, Manzi brushes the entirity of "social cost of carbon" into the potential decline in world economic product (a loss of approximately 3%). This not only excludes costs which I would deem "social" such as habitat and species loss, land degradation, and changes in local climate, but also aggregates the risk into a global pool, which is assuredly too crude a measure to make a meaningful judgment. To take the extreme case, what if the 3% loss were entirely distributed in 6% of the world's population losing half their economic productivity? The 3% measure looks small on paper, but in this instance 180 million people (over half the population of the US) just had their livelihoods utterly destroyed, to the point that they are now refugees. While this extreme concentration of risk is certainly fiction, it is patently clear to both the casual reader and the sophisticated analyst that the costs of climate change will not be equally distributed. The risks to the majority of the 160 million in Bangladesh should be enough to invalidate such crude aggregation of costs.
For another, in his association of all British driving taxes with "anthropogenic global warming (AGW)," he elides the myriad other costs of driving, including public health, land use, public land preservation, safety and enforcement, etc. Yes, once again these costs are difficult to quantify. This, however, does not mean they do not exist.
After dozens of paragraphs of analytical spinning, Manzi reaches the third to last, and engages in a breathtaking series of theoretical leaps. Costs are impossible to quantify, therefore "It becomes pure power politics," and therefore is a state imposition of economic costs without quantitative justification, and is therefore akin to total state planning of the economy. Excuse me, but WHAT?!?
To put this as simply as I can, there is a vast universe between "inability to sufficiently quantify" and "a different theoretical justification [for socialism]." What Manzi is experiencing is not the unearthing of socialist motives, but the limits of the quantitative revolution of the 20th century. There was a time, as strict Enlightenment rationalism and to a lesser extent, positivism reached their zenith, that we supposed that all complex issues could be solved with sufficient quantitative analysis. Difficult questions such as the costs of action or inaction on climate change demonstrate this as well as anything, but the lesson to take here is not that we have no analytical tools at all and retreat to pristine ideological tropes. (In this, I think Manzi is unintentionally making what I might call the Bachmann move — it's impossible to quantify, and it involves government action, therefore it is the first step towards tyranny.) Rather, it should be a clarion call to dust off analytical methods tossed aside during much of the quantitative revolution, such as informal logic, deep description, dialectics, rigorous observation, ethics, and comparative studies. (One can even retain critical rationalism, just without getting lost in numbers.)
Another reader makes a common criticism
There are usually many reasons to do something, and arguably there are more important reasons to tax carbon, and especially gasoline. Here are two off the top of my head: Decreasing our dependence on imported oil would make the Mideast a heck of a smaller powder keg. And since oil is a finite resource, it makes sense to conserve it if there are viable alternatives available. More electric cars and nuclear power plants, for example, would address these issues as well as those associated with AGW, and why not pay for it (in part) with a tax on gas?
Another reader:
Your argument has several fundamental empirical flaws and at least a few fallacies. First, your assertion that the IPCC's report provides a probability distribution that suggests at most a 3% decline in world GDP based on the most likely scenario is technically accurate, but ignores the data that has emerged since the report was written. In terms of ocean temperature increases, glacial and arctic sea ice melting, and total carbon released into the atmosphere, we've already exceeded the IPCC's most pessimistic trend forecast (remember, their trend forecasts were actually based on the belief that states would at least attempt to abide by the Kyoto Protocol). Updated modeling has placed so-called "tipping point" thresholds, which would result in substantial economic losses, to within 50 to 75 years rather than 100 to 150. In other words, the IPCC's existing probability distributions for "worst case scenarios" are already outdated.
Since the IPCC's report, new evidence has come to light of biological and climactic processes that make it even more likely that a worst-case scenario might emerge before the end of this century. This includes research on ocean acidification, the role of latent methane found in the slowly thawing subarctic tundra and deep within the ocean, and the masking effect of particulate pollution, which, once removed, will drastically increase ocean temperatures. You may be unaware of this research, but all signs seem to point to the unfortunate conclusion that the IPCC report was far too conservative.
This is all important because your argument rests on an assumption that the risk is not high enough based on the available evidence to warrant internalizing the costs of producing carbon. We now know that the risk appears to be rising, along with the potential costs if the problem is left unaddressed. Unlike congestion or noise, where costs are both well-known and hold a linear relationship with policies meant to address them. The costs of accumulating CO2 in the atmosphere are simply not well known and even the best economic models are mere guesses at the actual cost (primarily because, as you rightly point out, the problem involves so many potential counterfactuals). There's a very real possibility that the costs might be so high some time in the near future that eventually any expense will be justified, including your doomsday scenario where we all collectively turn off our cars and shutter the power plants. What we do know is that there is a substantial lag between the release of CO2 and its effect on Earth's climate, which means if we wait to see whether the cost will really materialize we will probably have waited too long to prevent costs from rising exponentially. Thus we may be facing the choice of a small investment now to slow the process versus a very large investment in the future to mitigate its effects.
Finally, by far the weakest part of your argument is the notion that a carbon tax represents anything close to"rapid, aggressive emissions abatement": A carbon tax, or a cap and trade system, will provide only a sliver of relief from CO2 emissions, especially at the weak levels being proposed in legislation before Congress. This is a very modest proposal, similar to laws put in place to limit alcohol or cigarette consumption. In America, as in another other advanced industrialized economy, we tax things that people earn and consume. It's no more fair or unfair than being taxed by the state of New York for registering my vehicle. The vehicle registration is not prohibitive. I still drive my car despite being forced to pay it. And, corporations will still produce the same goods and services, but will hopefully use energy from sources less likely to release CO2.
Your attempt to belittle the carbon tax as ineffective is a bit disingenuous since your real argument is that no effort on the part of the U.S. government justifies the cost of abating what you see as a relatively minor problem that has a very very low probability of becoming catastrophic. Thankfully, that's a position that can be proven or disproven over time as we start to see the actual effects of climate change. As for your view on taxes and socialism, I respect Hayek's argument and the potential that such a tax, implemented poorly or set too high, could lead to a loss of individual freedom, but I'm unaware of any system of government that has provided for the public welfare without a tax, and I do believe that ameliorating the effects of climate change provides a substantial benefit to public welfare, so on this we'll have to disagree.
Another:
Mr. Manzi wrote “In order to set the tax, we don’t just need to know the costs created by [anthropogenic global warming]… but rather all of the social costs and benefits created by the activity, which is far harder.” This is just a mistake. Unless the market is generally defective, prices should naturally incorporate these costs and benefits. It is because there’s a sort of point defect – the market’s inability to price in carbon externalities – that we discuss carbon taxes or whatever. It’s true that determining the actual degree of the externality is controversial and can plausibly be argued to be intractable, but correcting for an externality does not require calculating all downstream effects, and it is that asseveration in Manzi’s post that imports “socialism” into the discussion.
A final reader:
1) Manzi writes: "According to the authoritative U.N. Intergovernmental Panel on Climate Change (IPCC), under a reasonable set of assumptions for global economic and population growth, the world should expect (Table SPM.3) to warm by about 2.8°C over the next century. Also according to the IPCC (page 17), a global increase in temperature of 4°C should cause the world to lose about 3 percent of its economic output. So if we do not take measures to ameliorate global warming, the world should expect to be about 3 percent poorer sometime in the 22nd century than it otherwise would be." – Economics is a system created by humans, and it measures only a very limited part of human life: Productivity. It's precisely a retreat into the economic that allows people to dismiss concerns over things like climate change. Since the Industrial Revolution we have been engaged in a relentless search for 'efficiency', the maximization of productivity and profits at any cost, and it's gotten us a long way. But we are now seeing its limits. How many 'units of social cost' is the existence of polar bears worth? It's not worth any percentage points of productivity on an economic scale, but polar bears (and clean, fresh air, and beautiful natural places, and all the rest of it) sure do seem important.
4) Following off the same quote I pulled, I'd like to make what I consider my most important point. It's a question, a question that I've never really seen asked properly and that I'd love to hear Manzi's answer to: How long are we trying to keep this humanity thing going? He points to the statistic that temperature will rise less than 5 degrees in the next century, and says that means something as if that were the upper boundary of life on earth. Even in terms of human civilization (forgetting geologic time) a hundred years is not very long. So say in a century the earth is 4 degrees hotter, then what? We care about our children and grandchildren, but screw THEIR children and grandchildren? Is that really the attitude that Manzi is suggesting we adopt? We may not get very far down the path towards an uninhabitable earth in the next 100 years, but we're still on that road. Isn't that automatically an emergency?
The Dish 