So, with the government moving to implement a carbon tax, the issue of climate change and attempts to mitigate it are once again a big deal here in Australia.
Inspired by a friend's comment comparing carbon taxes with fines for littering, along with a few of the responses to that comment, I started pondering the similarities and differences between the current attempts to deal with carbon dioxide emissions, and the effective cost internalisation schemes created in the 1990's that severely reduced industrial sulphur dioxide emissions, as well as various current laws that prohibit dumping of toxic waste in developed nations (and their unintended side effects).
(Fair warning before I wade in: I've simplified quite a few things, particularly on the acid rain front. This post is long enough as it is, without making it even longer with all the relevant caveats about other causes of acid rain and any other details I've glossed over as being irrelevant to the main point of the article. It's a general overview, not a peer reviewed scientific paper)
A tale of two gases
The key similarity between sulphur dioxide induced acid rain and carbon dioxide induced global warming is hopefully fairly obvious: they both represent a classic economic "externality", a cost borne by someone other than the person responsible for causing it. The industries and individuals emitting these pollutants don't suffer any immediate harmful consequence through the normal action of nature.
In situations like that, regulation in one form or another is the only effective tool we have to ensure that at least some portion of those external costs is reflected back on the responsible individuals. As noted in the link above, this approach proved extraordinarily effective in reducing acid rain in the US, drastically cutting sulphur emissions at a fraction of the originally predicted cost.
However, there are a few key differences that have contributed to the discussion over carbon dioxide taking a rather different path to that over sulphur dioxide:
- It's hard to deny the harmful effects of sulphur dioxide emissions when plants, fish and insects are dying due to the excessive levels of acidity in rain and ground water. By contrast, it is very hard to convey clearly why a small rise in average global temperatures is going to be such a bad thing, or even how human carbon dioxide emissions contribute to that happening.
- Acid rain from sulphur emissions is generally a local problem with local causes (from a continental perspective, anyway). Stop emitting sulphur dioxide in the US and acid rain stops falling in the US. Significantly reduce carbon dioxide emissions in Australia (or even the US) though, and we're likely still screwed if other countries don't follow suit.
- The "sulphur" cycle (how long it takes for the sulphur emissions to be deposited back on the ground as acid rain) is significantly shorter than that of carbon, so efforts to reduce emissions will have an effect on water acidity levels in a reasonably short time frame
Manufacturing doubt and exploiting the "Grey Fallacy"
Acid rain is an easy problem to sell: the acid damages plants and objects directly, so the harm can be easily conveyed through pictures and videos. The problem of climate change, though is far, far harder to illustrate simply, since it is a signal buried in some very noisy weather patterns.
A fundamental issue is the fact that people don't really experience climate, but instead experience weather. The day to day and seasonal variations in the weather massively exceed the scale of the underlying trends being discussed by climate scientists. The fact that predicting the weather in a few days time is harder than predicting long term climate trends is actually massively counterintuitive, even though almost all scientists and engineers are familiar with the fact that random fluctuations at a small scale may average out to something almost perfectly predictable at a large scale (compare the unpredictable nature of quantum physics with the straightforward determinism of classical Newtonian mechanics).
We're also not really used to the idea of directly affecting the balance of the planet on a global scale. In absolute terms, the effects of the sun, the oceans and the plants on the carbon cycle all dwarf the human contribution. The idea that the non-human forcings were actually largely in balance with each other, and that the comparatively small human contribution is enough to tip that balance to the point of producing more carbon than can be absorbed by natural mechanisms is really quite a subtle one.
The scientific background needed to truly understand and come to grips with the hows and the whys of the IPCC predictions reminds me of this comic regarding the knowledge needed to even begin to understand the vagaries of string theory (make sure to click through on the comic itself to see the whole chain of images).
If there wasn't anyone around with a vested interest in maintaining the status quo (at least for a while longer), this likely wouldn't be a problem. Scientists, politicians, economists and engineers could proceed with the development of mitigation strategies, while also attempting to educate the general populace as to the reasons behind any actions taken. Since such vested interests do exist, however, their opposition makes it significantly harder to convince the lay public that there is a real problem here.
Because climate science is such a complex topic, it is actually quite hard to explain to a non-scientist just why the scientific consensus is as strong as it is. If you oversimplify, you veer into territory where statements are so oversimplified that they border on being false. However, if you're coming from the other angle and want to persuade people that the science "isn't settled", then you're no longer constrained by the need to be accurate and can just go with whatever sounds more intuitively plausible and/or better caters to people's natural inclinations and prejudices.
Sites like Skeptical Science do their best to clearly explain why the oft-repeated "skeptic" arguments are basically BS (and do it well), but to someone only following the Cliff Notes mainstream media version of the debate, the temptation is still very, very strong to just assume the truth lies somewhere between the two positions being debated.
Telling people to "do their own research" doesn't really help all that much in practice. Telling the BS from the valid science is itself a fine art that takes a great deal of skill and experience. Being a veteran of arguments with creationists (and even intelligent design advocates) is actually quite beneficial, since the global warming "skeptics" use many of the same rhetorical tricks as creationists do when attempting to deny the fact of evolution (incessant use of such deceptive tactics is actually one of the major hints that someone is trying to sell you a line rather than just stating the truth as they see it). The most common tactic used by both groups is to drag out a thoroughly rebutted argument for each new audience, in hopes that they aren't aware of the existence of a rebuttal.
For example, just as most people can't answer "How could a bombardier beetle possibly evolve?" off the top of their heads - I've actually forgotten all of the plausible answers myself - neither can they answer questions like "If the climate is supposed to be warming, why is it colder now than it was during the Middle Ages?". While that one is actually fairly straightforward to answer (ice cores and other data shows that the medieval warming was likely localised to Europe due to various currents in the Atlantic, but this merely shifted heat around, so that other parts of the world were correspondingly colder), there are dozens of other oft-repeated thoroughly debunked arguments, and it's basically impossible for a mere interested observer to remember them all. As it turns out, I had actually misremembered the correct explanation for the Medieval warm period, so the point above isn't quite right and invites an attack on the grounds that I don't know what I'm what I'm talking about. To some extent that's actually true - my opinion on climate science issues is based on a meta-analysis of the trustworthiness of various information sources (including the full IPCC reports), since I'm not inclined to spend a few decades studying up and redoing all the science myself. Fortunately, Skeptical Science has the full story for this question and many others (the MWP was actually colder than the latter half of this century, despite higher solar activity and lower volcanic activity), so correcting my error is the task of a few moments. And if you're still wondering about the bombardier beetle thing, TalkOrigins has the full story for that, too.
Fortunately, at the decision making level here in Australia, this part of the debate seems to be coming to a close, with even Toby Abbott (the leader of the opposition) at least paying lip service to the fact that human-induced increases in average global temperatures are now a fact of life. However, the mainstream media is still happy to "teach the controversy" in the hopes of picking up a few more eyeballs (or ears) to sell to their advertisers.
But the problem is so much bigger than us!
However, even once you get agreement that human-induced global warming due to excessive carbon dioxide emissions is a genuine problem, you then run into the "But we can't do anything about it!" attitude.
Many Australians (including some elected members of our Federal parliament) go "Oh, but the US/Europe/Brazil/Russia/India/China have a much bigger impact than we do. Doing anything will hurt our international competitiveness without really achieving anything, so we shouldn't bother."
Even the higher emission countries point fingers at each other. The US won't budge until China does. The BRIC countries are waiting for the US to make a move, and use US inaction as justification for similarly doing nothing in the meantime.
An absolutely textbook "Tragedy of the Commons" reaction. And we know how that story ends, don't we? In the long run everybody loses, nobody wins.
How do you fix it? Rules, regulations and social pressure. The "community of nations" isn't just words. The complex web of interdependencies that spans the world gives countries real power to exert influence on each other. Once some countries start to make a move towards serious carbon emission control strategies, then that becomes a bargaining chip to use in international negotiations. Will it work? Who knows. The only thing we know for sure is that the more carbon we pump into the atmosphere over the next few decades, the higher the impact from global warming will be (it's now guaranteed that there will be some impact - the carbon cycle is too long for us to prevent that at this late stage of the game).
Ideally you would want to adopt an emissions trading scheme along the lines of that used to curb sulfur emissions, but the wholehearted embrace of dodgy pseudoscience by far too many members of our Federal Opposition party spiked that particular barrel.
So a carbon tax it is (for now, anyway). The hysterical cries of "Oh my god, you've doomed the country!" ring loudly from those that will bear most of the direct costs of actually internalising the negative effects their carbon emissions have on the wider environment. Their motives are, to say the least, a little bit suspect. The political opportunism involved in our Federal Opposition leader backing them is disappointing, but unsurprising.
In the PM's words
There's a nice summary of the current situation in a Fairfax opinion piece that went out over Gillard's byline:
The longer we leave it the harder action on climate change gets. This reform road is a hard one to walk. Just as doing nothing is not an option, we need to be careful to ensure that we do not make decisions that will cost our economy and jobs.There's a definite risk that the government's plans won't live up to their ambitions. However, the world's past experience with the sulfur dioxide doomsayers should arouse some deep skepticism and not directed towards those wanting to press forward with plans to curb carbon emissions.