Category: The environment

Atmosphere, biosphere, lithosphere, hydrosphere, etc – everything about life and the state of this planet

Abbreviation confusion

Signal that you spend too much time thinking about climate change: you see a teenager wearing a shirt that says ‘THC’ and assume he is expressing concern about the integrity of the thermohaline circulation.

Incidentally, it is worth remembering the difference between acronyms (which use the first letters in a phrase to produce a word you can speak) and abbreviations, which are spoken letter by letter. As such, ‘self contained underwater breathing apparatus’ becomes the acronym SCUBA while ‘United Nations Framework Convention on Climate Change’ becomes the abbreviation UNFCCC.

Climate change impacts, ranking severity

These are summer days and the blogging is slow. In the spirit of audience participation, here is a quick poll.

Which three of the following climate change impacts do you expect to be the most severe? Please answer first for 2050 and again for 2100. You can interpret ‘severity’ however you like: economic cost, number of deaths, total damage to ecosystems, etc.

  1. Sea level rise
  2. Droughts and floods
  3. Extreme weather events
  4. Ocean acidification
  5. Ecosystem changes (such as invasive species)
  6. Effects on pathogens (such as malaria)
  7. Agricultural impacts
  8. Impacts on fresh water quantity and quality
  9. Other (please specify)

Clearly, there is some overlap between the options. There are also second-order effects to be considered, like the impact of agricultural changes on inter- and intra-state conflict.

The media and climate change ‘dissent’

This Ron Rosenbaum article in Slate argues that it is inappropriate for journalists to portray “the anthropogenic theory of global warming” as an undisputed fact. It cites the importance of considering dissenting views, and asserts that the history of science shows that a consensus held by most of the scientific community can be wrong. While there is some value to both arguments, I think they are weaker than the counter-arguments, in this case.

Starting with dissent, we need to appreciate the character of the consensus on climate change and the character of opposition to it. As discussed here before, there are areas of greater and lesser certainty, when it comes to climate change. What is absolutely certain is that we are increasing the concentration of greenhouse gasses in the atmosphere and that, in turn, causes more energy from the sun to be absorbed. The precise consequences of that overall warming are not known with certainty, but we do know enough to have very good reason to be worried. Arguably, those dissenting from this view are a combination of the self-interested (industrial groups reliant upon heavy emissions, conservative ideologues opposed to government regulation) and conspiracy theorists. The doubts of legitimate scientists establish the areas of uncertainty within climatic science, including questions about the strength of feedback mechanisms, the effects of planetary warming on regional weather, and so forth.

On the matter of scientific consensus, the article argues that a “lone dissenting voice of that crazy guy in the Swiss patent office” overthrew the Newtonian conception of gravity. This is a relatively absurd claim. Firstly, relativistic physics essentially includes Newtonian physics as a special case, in situations where velocities are not close to the speed of light and massive objects are not close at hand. Secondly, the process through which Relativity became an established scientific theory was largely focused on the collection of empirical evidence (demonstrations of gravitational lensing, for instance) and the refinement of the theory within the scientific community. Newtonian physics, for its part, is still completely adequate for planning space voyages within our solar system – the basic relationships posited within it are close to correct in most cases. If we have done so well with our climate models, we have engineered them effectively indeed.

Relations between science and the media will always be challenging. The media generally doesn’t have the time, expertise, or interest to deal with nuance. It also lacks an audience interested in cautious and non-confrontational assessments of fact. In short, the kind of story that is demanded of the media is one in which the scientific process and the character of scientific conclusions cannot always be presented effectively. Moderating some of the incentives to distort that are inherent to the contemporary practice of journalism is thus an undertaking with some merit. It is not as though we should forbid any mention of opposition to our general understanding of climate change; rather, journalists should strive to make clear that the evidence on one side is overwhelmingly stronger than that on the other. A defendant who was seen to stab someone in the middle of the field at the Super Bowl, viewed by millions of people, surely has the right to make a defence at his trial. He does not have the right to media coverage that gives equal weight to claims that he had nothing to do with the death.

Temperature and extreme weather

A new article in Science provides observational evidence of the link between rising temperatures and extreme weather events:

These observations reveal a distinct link between rainfall extremes and temperature, with heavy rain events increasing during warm periods and decreasing during cold periods. Furthermore, the observed amplification of rainfall extremes is found to be larger than predicted by models, implying that projections of future changes in rainfall extremes due to anthropogenic global warming may be underestimated.

Of all the impacts of climate change, extreme weather seems especially likely to help spur mitigation action, especially when that weather occurs in rich states. Reasons for that include the visibility and newsworthiness of floods, droughts, hurricanes, and so forth. Another major factor is the importance of the insurance industry, especially insofar as their professional estimations of risk affect the cost and feasibility of different projects. That is, so long as policy-makers do not establish incentives for risky behaviour.

Nanomaterial safety

When it comes to geological periods of time, our intuitions about how things work cannot be trusted. This is a reflection of the parochial character of many of the heuristic shortcuts in our minds. The same thing applies to the behaviour of objects at a minute scale. For instance, sufficiently tiny machinery is hampered enormously more by friction and surface tension than a larger equivalent would be. Because they have more surface area relative to their volume, they also tend to be much more reactive.

Indeed, asymmetries of behaviour at different scale raise serious concerns about the safety of newly developed nanotechnologies. Just as our brains are calibrated to deal with the kind of experiences that have been normal to human lives for thousands of years, our regulatory procedures are calibrated to respond to known risks like toxicity or corrosiveness.

There have certainly been serious problems that arose from regulation lagging innovation in the past. Think of ozone-destroying chlorofluorocarbons, or mesotheliomas caused by chrysotile asbestos. Balancing safety concerns with the desire not to stifle innovation is extremely challenging, especially when the entities with the most sophistication in relation to a new technology are its commercial backers.

In some cases, nanomaterials have almost completely escaped regulation because it has been assumed they behave like their non-nanoscale equivalents. That said, nanoscale titanium dioxide is not the same as a macroscopic bar of the stuff. The same is true for carbon nanotubes, silver nanoparticles, and so forth. Indeed, if the substances were equivalent, there would be no promise in nanotechnology itself. Especially when it comes to the exposure of nanoparticles to human beings (though food, cosmetics, etc), it makes sense for the nano-versions to be regulated as new substances, with the onus on the manufacturers to demonstrate safety.

Long-term natural climatic variation

One thing that only seems to be understood to a limited extent in most quarters is the degree to which humanity faces very serious long-term climatic challenges, even in the absence of human greenhouse gas emissions. This is simply because there is no reason to believe that the kind of climate that has existed for most of human history is one that is uniquely probable and likely to persist. Ongoing forces like plate tectonics, the development of carbon-rich rock through the weathering of mountains, and orbital variations (Milankovitch cycles) all have marked and overlapping effects in the long term. Paleoclimatological evidence shows a world that has differed considerably in temperatures, weather patterns, and continental layouts. Oxygen only emerged in the atmosphere 1.7 billion years after the Earth formed (though because of biological developments, rather than climatic ones). During the late Precambrian period, Earth was essentially a giant snowball. At times, evidence suggests that Antarctica hosted deciduous forests rather than an ice sheet. It seems that sometimes the forces that caused transitions from one state to another were relatively minor in and of themselves: they just pushed the overall climate system in a self-sustaining direction.

Of course, long-term natural climatic variation on the scale of hundreds of thousands or millions of years is a much less immediate concern than the consequences of humanity’s continued use of the atmosphere as a carbon dioxide dump. The latter is a real and massive immediate threat, while the latter is more of an academic consideration for the moment. That being said, it does seem important to understand that our present conditions are not some robust preference emergent from the fundamentals of the climate system; rather, it is one equilibrium among many. In a manner somewhat akin to learning that our planet/solar system/galaxy is just one of a vast multitude, this should prompt humanity to re-examine some of our beliefs about our own importance and about the stability and habitability of the planet we inhabit.

McKinsey ranks mitigation technologies

In the past, I have mentioned both marginal abatement cost curves for greenhouse gasses (curves that describe the cost of eliminating each successive tonne of greenhouse gas) and the economic analyses done by McKinsey. Recently, a friend reminded me of an informative graphic from one of their reports:

The whole report is available online. All the options listed on the left hand side, below the horizontal line, are actually projected to save money as well as reduce greenhouse emissions. Those to the right are progressively more expensive, up to about 50 Euros a tonne.

The graphic is quite interesting because it shows a ranking of the cost at which different technologies can achieve emission reductions. It’s also interesting that they projected how many technologies need to be implemented – and to what degree – to achieve stabilization of greenhouse gas levels at 550, 450, and 400 parts per million of CO2 equivalent.

Put on a graphic like this, it all looks very achievable.

Shifting baselines, oil and ice

One of the more interesting environmental blogs I read is Shifting Baselines: a fisheries focused site that concentrates on how our changing expectations about life in the sea conceal from us the gradual emergence of long-term changes. A couple of other shifting baselines have caught my attention recently. They have to do with the long term trends of Arctic sea ice depletion and increasing oil scarcity. In both cases, exceptional shifts in the recent past have given way to what look like temporary reprieves.

Last summer’s Arctic sea ice minimum was a major record-breaker. It sparked serious thinking about whether the Arctic summer could be ice-free within a decade. This summer’s melt now seems likely to be less severe. Does this mean our level of worry should diminish, or is this simply oscillation around a worrying downward trend? It certainly gives ammunition to those who would like to deny that there is a trend at all. In the long run, it probably doesn’t matter enormously whether the Arctic melts in ten years or thirty. Where it may matter considerably is insofar as awareness of Arctic melting either prompts the emergence of strong climatic policies or provides fodder for those who want to continue to delay.

The same might be said about the recent slip in the price of gasoline. That being said, the nature of the causal factors at work there seems more straightforward. Prices do not seem to be falling because supply constraints have been lifted. Rather, they are falling because people are cutting back on usage: both as a result of general economic weakness and as a result of high energy prices themselves. High gasoline prices are something of a double-edged sword for environmentalists. On the one hand, they do help to encourage investments in efficiency. On the other, they encourage the development of truly filthy alternative sources of fuel (like the oil sands), encourage the development of false solutions (like corn ethanol), as well as making it more challenging politically to support sound environmental policies.

Whether it is ice or energy under consideration, the general lesson of shifting baselines is pertinent. We need to see past short term trends and our focus on how the recent past and the present compare, looking onwards to fundamental forces and long-term developments. Of course, when it comes to systems as massive and complex as the global climatic and economic systems, doing so is enormously difficult.

Honey and veganism

This Slate article on honey and veganism makes some good points: most notably about the inconsistency between refusing honey on ethical grounds and accepting fruit that is pollinated by domesticated bees. Not eating anything that requires bee labour for production rules out “almonds, avocados, broccoli, canola, cherries, cucumbers, lettuce, peaches, pears, plums, sunflowers, and tomatoes.” In theory, one might be able to find some of these things grown only with the assistance of naturally occurring pollinators, but I doubt it is something most honey-shunning vegans have even considered.

My personal position, as described before, is that there is no fundamental problem with using animals for food. The problems arise when it is done in an environmentally unsustainable, unhygienic, or morally unacceptable way. The latter condition means that, when animals above a certain threshold of sentience are involved, they cannot be treated in a way fundamentally contrary to their nature. In the case of bees, I would argue that they fall below the sentience threshold. While it is impossible to determine, at this time, whether they are capable of experiencing suffering, forming complex thoughts, and so forth, it seems plausible to conclude that they generally cannot, and are thus more on par with protozoans, plants, and fungi than with complex animals. I don’t claim that this moral code is entirely comprehensive or internally consistent, but it presently strikes an acceptable balance between my level of concern and the amount of time I am willing to spend pondering such questions and taking actions required in order to not contravene them.

In addition to honey, I generally disagree with the vegan objection to wool. There doesn’t seem to be any fundamental cruelty or desecration involved in the shearing of sheep, though I should probably investigate the conditions in which sheep used for wool production are raised and live.

More on food, ethics, and the environment:

There are many more, but that list should get the curious reader started.