Month: September 2008

A Wikipedia paradox

The site is most useful when you know either absolutely nothing about something, or a great deal about it. It permits those utterly unaware of a topic to get some essential facts – probably true – very quickly and easily. It also allows real experts to track down something they once knew, can remember, but had forgotten very quickly.

Wikipedia is least useful for those in the middle zone. These are people who know more than the minimum, but not enough to really judge the credibility of complex arguments in the subject area.

Nonetheless, it is a wonderful resource. I use it at least twenty times a day.

How much carbon dioxide can we release?

Climate sensitivity is the amount of warming that would arise from doubling the concentration of carbon dioxide in the atmosphere. The IPCC estimates that it is between 2.0˚C and 4.5˚C, with 3.0˚C as the most likely value. They also warn that, because of feedback effects, “values substantially higher than 4.5˚C cannot be excluded.” Basically, this number refers to how many degrees of warming would arise from raising the concentration of CO2 in the atmosphere from the pre-Industrial level of 290 parts per million (ppm) to 580 ppm: 50% above today’s level of 385 ppm. The higher the number, the worse the consequences from any particular level of emissions.

We can combine that figure with the maximum amount of warming we are willing to tolerate and come up with a figure for how much more carbon dioxide humanity can release, all told. Using the 2˚C ceiling adopted by the European Union and endorsed by 200 of the world’s top climate scientists, Andrew Weaver worked out what those limits would be for different climatic sensitivities:

  • 2.0˚C sensitivity – 1314 billion tonnes (gigatonnes) of carbon – 4822 gigatonnes of CO2
  • 3.6˚C sensitivity – 661 billion tonnes (gigatonnes) of carbon – 2426 gigatonnes of CO2
  • 4.5˚C sensitivity – 484 billion tonnes (gigatonnes) of carbon – 1776 gigatonnes of CO2
  • 8.0˚C sensitivity – 163 billion tonnes (gigatonnes) of carbon – 598 gigatonnes of CO2

The 2˚C and 4.5C figures are the top and bottom of the IPCC’s probable range. The 3.6˚C figure is the one considered most probable by those running the University of Victoria climate model. The 8˚C figure illustrates the impact of much higher sensitivities on how much can be emitted.

Current annual carbon dioxide emissions about ten gigatonnes of carbon (36.7 gigatonnes of CO2) per year. Note that the figures above are how much CO2 can be emitted in total before the whole world becomes carbon neutral – certainly not about how much can be emitted before we need to begin cutting. Those totals need to include all future emissions from developed and developing states alike, between this year and whichever year the world achieves carbon neutrality.

The 4.5˚C scenario implies a peak concentration of 445 ppm – slightly lower than a commonly cited ‘safe’ level. Some people – notably James Hansen – have argued that an even lower stabilization concentration is necessary to avoid runaway climate change.

Unreliable Sylvania

The two selling features of compact fluorescent bulbs are higher efficiency (more light produced per unit energy) and longer lifespan, when compared to incandescent bulbs. We have already established that the first isn’t a concern for people actively heating their homes. My recent experience with the second is also rather negative. I recently replaced as many bulbs in my house as possible with fluorescents. In the month and a half that followed, four of the bulbs failed: those in my kitchen, on my back porch, and in my front hallway.

I have never had incandescent lights fail so quickly. It’s not clear what caused these ones to die so abruptly (A manufacturing defect? Problems with my power supply?), but it will definitely prevent me from buying Sylvania brand bulbs in the future.

Ethics embedded in economics

I recently attended a presentation on economic modeling, climate change, and the social cost of carbon. Initially, this was presented as a process where we took our best scientific information, fed it into our best economic models, and ended up with our best projections about how much harm climate change would do, and thus what the ‘social cost’ of carbon really is. The point I raised was that this approach is in no way divorced from ethical assumptions. Indeed, they are deeply ingrained in the economic models and have profound effects on how they turn out.

Here are a few of the most important aspects of that:

1) The discount rate: Nicholas Stern took a lot of flak for setting this value so low. Basically, it pertains to how much we value the welfare of future generations. The lower you set it, the more the welfare of future generations will affect your calculations. In financial planning, discount rates are often in the neighbourhood of 8%. That means we would be indifferent to having $X today or $X + 8% in one year. The trouble is, with a value that high the welfare of distant future generations becomes almost completely unimportant in your calculations. If we knew that climate change would instantly kill everyone alive in 100 years, using an 8% discount rate would make this fact largely unimportant in terms of working out what the ‘social cost’ of one tonne of carbon is today.

Of course, there are problems with using a very low discount rate as well. If we care as much about all future generations as about our own, we are compelled to put all of our wealth towards investments for them. After all, current spending only benefits us, whereas investment could increase the welfare of a potentially infinite chain of future generations.

In any case, the discount rate selected has a massive effect on what social price for carbon you end up with. Stern worked it out as about $85 per tonne. William Nordhaus, another economist, came up with a figure of $7, largely because he used a higher discount rate. This one choice has the power to massively affect any economic analysis of climate change.

2) The marginal utility of income Take $100 per year from Bill Gates and he will never notice. Take it from everyone living in Sub-Saharran Africa, and you would probably kill millions. Despite this, most economic models assume that a dollar is a dollar is a dollar. If melting permafrost makes us abandon a northern community, at a cost of $20 million, but the cost to Canadian industry of avoiding the emissions that caused it would have been $21 million, the economically optimal outcome would be to allow the community to be destroyed.

To some extent, this can be built into economic models. We can create a mathematical function for how useful each extra dollar a person gets is. If we use that ‘utility’ measure in place of a dollars measure, the impact of different choices on the least well off becomes more important. Actually doing so on climate change would almost certainly hugely increase the social cost of carbon, since the welfare of those threatened by sea level rise in Bangladesh and drought in Sudan would be considered on more equal terms to wealthy Floridians with property threatened by hurricanes and oil company employees hoping to exploit new fields in the Arctic.

In addition to having economic importance, this has massive ethical importance. An approach based on potential Pareto optimality supports any move that improves overall welfare. It doesn’t matter if the people gaining are residents of suburban Toronto while those losing live in villages in Ghana. In everyday life, we recognize that we cannot go around harming people just because we gain more from doing so than they lose.

3) Valuing catastrophic risks If we manage to turn the world’s carbon sinks into net sources, we will have created self-sustaining climate change. If that occurs at an accelerating rate, we will be facing runaway climate change, which threatens to cause enormous physical changes and mass extinctions – possibly including humanity itself. Integrating such possibilities into economic models requires a number of ethical assumptions. Even a very small possibility of such an outcome can have a giant influence on certain kinds of models; likewise, choosing to ignore such outcomes has highly ethically relevant effects.

In short, we cannot combine scientific and economic models and produce a technocratic answer about how much climate change should be permitted. We need to acknowledge and consider the ethical implications built into and arising from those models, we need to choose what kind of world we want to hand over to future generations, we need to consider how important we think responsibility for the problem is when allocating costs, we need to consider the special circumstances of the very poor, and we need to consider how big a risk of catastrophe we should really tolerate.

I think an honest examination of those issues, alongside the best climatic science we have, creates a powerful and immediate ethical and economic argument for change. It is virtually certain that – if they could speak to us – people fifty or one hundred years in the future would be screaming at us to do dramatically more than we are doing now.

Am I a ‘conservative?’

The other day, a friend of mine somewhat surprised me by referring to me as a ‘conservative.’ Pressed to define myself, I would say that I am a pragmatic libertarian who is willing to recognize that our freedoms need to be constrained in many ways in order to live decently together.

The Political Compass test categorizes me as follows: moderately left wing on economics (-3.00) and strongly slanted towards libertarianism rather than authoritarianism (-6.67).

I do object to some of the questions they pose. For instance:

  1. If economic globalisation is inevitable, it should primarily serve humanity rather than the interests of trans-national corporations – It is a bit silly to say that globalization serves one or the other, or that corporations are purely abstract entities whose welfare has nothing to do with individual people.
  2. The only social responsibility of a company should be to deliver a profit to its shareholders – This seems like an oversimplification of a complex question. Clearly, corporations have a general obligation to obey the law (though those in them may sometimes be morally obliged to break unjust laws). It certainly isn’t clear that the directors of corporations should undertake charity using shareholder wealth.
  3. First-generation immigrants can never be fully integrated within their new country – This clearly depends on what constitutes integration. For instance, when there are societies that have multiculturalism and inclusiveness as important features, people can be integrated without being assimilated.

The test also features a number of confusingly worded multiple-negative items. “Is X not true? No.” There are also a few questions seemingly designed to establish whether you are a racist. It seems to me that there have probably been racists of all possible political affiliations.

Personally, I would say my political philosophy is a combination of some classically liberal ways of viewing the world coupled with a libertarian concern for the individual and a utilitarian concern for group welfare. I would say that I am also unusually aware of the extent to which seemingly private decisions (what to eat, how to travel, etc) have significant and morally relevant impacts on other people.

May on the train

Kudos to Green Party leader Elizabeth May for using her campaign to draw attention to the unsustainable character of air travel. Rather than fly all over the country to court voters, she has opted for a far less carbon-intensive train based approach. One round-trip journey from Toronto to Vancouver emits about 1,700 kilos of carbon dioxide equivalent. A train journey emits about 730kg: about 60% less. That is not enough of a reduction for trail travel as presently undertaken to be genuinely sustainable, but it is a significant step in the right direction. People would also probably think more about long-distance transport if it took a few days rather than six or seven hours.

The linked CBC article does get one thing wrong, however. It says: “Other observers have pointed out it is probably cheaper than flying, too.” As discussed here before, taking the train seems to be more expensive. At present, a return ticket between Toronto and Vancouver is running for $1,390.20 plus taxes. WestJet provide the round-trip transport for $439.25 after taxes.

Spore tip: species for terraforming

There is no quicker way to make money than to develop a bunch of T3 planets that are close to one another and which produce valuable forms of spice. Getting planets to T3 can be a pain, however. This is largely because you will need three species of small, medium, and large plants; six species of herbivores; and three carnivores or omnivores.

The easiest way to get them all – and avoid repeats – is to dump all the species you are carrying, visit an existing T3 planet (like your homeworld) and collect a dozen or so of each species present. You will then have a hold full of terraforming goodness.

Temperature, humidity, and precipitation

The amount of water that can be dissolved in air changes as a function of the temperature. In general, this means that increasing the temperature of air by 1˚C increases how much water can be dissolved in it by 7%. The precise values for any temperature change can be calculated using the Clausius-Clapeyron equation.

This is relevant to climate change for two reasons. Firstly, water vapour is a powerful greenhouse gas. Higher temperatures cause more evaporation and allow air to be more water-saturated, thus permitting further warming. Secondly, increased temperatures affect precipitation patterns through changes in the water capacity of air. The general trend is towards more extreme precipitation, more drought, greater annually averaged precipitation in middle and high latitude locations, and decreased precipitation in the tropics.

Forget targets

The big picture on climate change is one of the composition of the atmosphere and the thermodynamic balance of the planet. It is a very complex and long-term story, some of which requires considerable scientific knowledge to grasp. The basics of it come out to this:

  • Humans are changing the climate.
  • Further change is profoundly threatening for humanity.
  • We need to stabilize how much greenhouse gas is in the atmosphere, and do so at a safe level.
  • This requires fast, deep cuts.

A lot of attention has rightly focused on emission targets and timelines: where we need to be by when to achieve the kind of outcomes we want. The trouble with this debate is that it is largely artificial. Candidate X might say: “Cut to 50% below 2000 levels by 2050” and Candidate Y might say: “Cut to 65% below 2000 levels by 2050.” The difference between the two outcomes would be important for the climate. At the same time, the difference between the candidates is actually much less about the targets and much more about the means of implementing them. Candidate Y might say: “Voluntary measures, technological progress, and magical future technologies will do the job” while Candidate X might say: “We will limit total emissions from our economy to 3% below this year’s level next year. We will charge firms for the right to emit this much. We will use that money to foster a transition towards a low-carbon economy.” Needless to say, the results of each plan will differ significantly by the time you get to 2050.

The critical thing right now is to bend the path of global emissions. Rather than moving ever-upward, it needs to turn downward and start the long decline towards a low-carbon economy. Achieving that is all about immediate measures, not about emission projections that delay most of the reductions for decades. While it is certainly cheaper to cut a notional tonne of emissions ten years out, it is also the case that starting the transition will be more difficult than maintaining it. As such, it would be good to see states and political parties competing over who will cut emissions more in the immediate future, rather than across timespans during which today’s leaders will be enjoying their retirements.

Of course, the political risks of cutting emissions now are comparatively large. When it becomes evident what that will involve, it might prove expensive and politically unpopular. Protecting the welfare of present and future generations might evoke the wrath of voters during the next election. Unfortunately but honestly, no politician can be expected to show such bravery. Even so, there is an opportunity to recast the narrative. Firstly, we need to stress that this transition simply needs to occur. The alternative to acting now is simply delaying to the point where the transition will cost more and the impacts of climate change will be more severe. Secondly, this is an epic opportunity for humanity and for individual states. We can finally move beyond a post-Industrial Revolution economy based on constantly borrowing from the welfare of future generations. We can create states and a global society than run on sustainably produced climate-neutral energy.

The action required to start doing so is needed immediately. Choose someone who promises to change something by next year, and turf them out if they don’t.

Comments? Counter-arguments?

Summer has passed

Some facts for the autumnal equinox:

  • The Earth has seasons because it orbits the sun while tilted 23.44˚ off the vertical axis.
  • This tilt varies with time, following a 41,000 year cycle.
  • At the maximum, the tilt is 24.5˚. At the minimum, it is 22.1˚. When there is more tilt, the difference between summer and winter increases. When there is less tilt, the seasons are more similar.
  • Along with the changes in the shape of Earth’s orbit (eccentricity – 100,000 year cycle) and the way the planet wobbles around the pole (precession – 26,000 year cycle), axial tilt (obliquity) contributes to the Milankovitch cycles – one of the major long-term drivers of natural climate change.
  • To learn more, look up Dansgaard-Oeschger events and Heinrich events.

Disclaimer: Yes, orbital and solar variations affect the planet’s climate. That doesn’t mean human greenhouse gas emissions don’t, nor that they aren’t the primary cause of the climate change presently taking place!