Science – Page 52 – a sibilant intake of breath

“Coal is the enemy of the human race”

The above wording is blogger David Roberts‘ attempt to summarize the relationship between humanity and coal in the 21st century. While many countries rely on it to produce electrical power and fuel other sorts of industry, there are huge negative externalities associated with it as a power source. These include:

Environmental destruction and contamination from coal mining.
Human health impacts from coal mining
Air pollutant emissions from coal burning, including particulate matter and mercury
Greenhouse gas emissions from coal burning
Toxic coal ash

A report from the US National Research Council found that American coal plants produce $62 billion per year in negative externalities, before climate impacts are taken into account.

Climate change is the biggest danger associated with coal. Firstly, coal produces a lot of CO2 per unit of useful energy. Secondly, coal reserves are so enormous that burning a significant fraction of what is left would essentially guarantee more than 2°C of mean warming globally, the level scientists and policy-makers have generally accepted as ‘dangerous.’

If it can prove safe, cheap, and effective, there may be a future for carbon capture and storage (CCS). Until that is demonstrated, we cannot assume that there is a future for coal as an energy source. Even before you take the climate impacts into consideration, the total costs are unfavourable compared to greener and renewable alternatives. Once climate change is factored in, the case against non-CCS coal becomes conclusive.

[16 February 2010] Now that I have a fuller understanding of the importance of not burning coal and unconventional fossil fuels, because of their cumulative climatic impact, I have launched a group blog on the topic: BuryCoal.com. Please consider having a look or contributing.

Long-lived nuclear waste warnings

In addition to the engineering problems involved in storing radioactive wastes from power plants and weapons programs, there is the additional difficulty of marking the storage sites as dangerous, in a manner that will be comprehensible throughout the period in which the wastes will be a hazard. In 1991, a report considered this question: “Expert Judgment on Markers To Deter Inadvertent Human Intrusion Into the Waste Isolation Pilot Plant.”

As reported in Slate:

“The report’s proposed solution is a layered message—one that conveys not only that the site is dangerous but that there’s a legitimate (nonsuperstitious) reason to think so. It should also emphasize that there’s no buried treasure, just toxic trash. Here’s how the authors phrase the essential talking points: “[T]his place is not a place of honor … no highly esteemed deed is commemorated here.” Finally, the marker system should communicate that the danger—an emanation of energy—is unleashed only if you disturb the place physically, so it’s best left uninhabited.”

They estimate that a system of redundant warning markers for an American nuclear waste dump would cost about $68 million.

The whole issue is a potent demonstration of the challenges contemporary technologies create, when it comes to our moral relationship with future generations. Just as they will be the ones who live with the climate change we produce, they will also have legacies like topsoil erosion and the accumulation of toxic and radioactive wastes to contend with.

Strategy for denier commenters

I am happy to say that traffic to this site has been steadily increasing. Visits are up 138% from last year, and October was our best month ever. Increasingly, a sibilant intake of breath is well ranked by search engines.

One problematic element that accompanies popularity is that I attract ever-more climate change deniers and delayers (those who accept that it is real, but think we should take no action). Ordinarily, I am happy to debate with people and try to provide quality information. That being said, it can take up a lot of time to try to refute those who repeat faulty arguments over and over. These people call themselves ‘skeptics,’ but I think they are mis-applying the term. I have yet to encounter one that is willing to back away from even thoroughly discredited positions. Instead, they just move on to another misleading argument.

The question, then, is how to deal with these commentors without losing all scope for socializing and personal projects. Some of the options:

Briefly assert that their position is incorrect and point to a resource that says why. Ignore further attempts at rebuttal.
Point all such commentors towards pre-existing posts and conversations, without offering specific responses.
Adopt the Zero Carbon Canada approach: “ATTN climate change denier trolls: you are cooking our kids and will be deleted.”
Continue to provide detailed, personalized responses as much as possible.

(1) and (2) are appealing because they reduce the extent to which one person seeking to spread disinformation can waste my time. That said, leaving comments unaddressed could lead readers to believe that the points made therein are valid. (3) is appealing because it would prevent bad information from appearing online, though it is obviously a form of censorship. (4) is the ideal world solution, though I do need to wonder whether refuting deniers and delayers in blog comments is really the best use of my time, even if all I am taking into consideration is whether I am acting effectively on climate change.

Which option do readers think is most suitable? Are there other options I ought to consider?

Debates within society at large, and within the scientific community

Elaborating on work discussed here before, Gavin Schmidt provides some information on what distinguishes the most recently developed sorts of climate models for their predecessors, such as General Circulation Models. The newer Earth System Models:

now include interactive atmospheric chemistry, aerosols (natural and anthropogenic) and sometimes full carbon cycles in the ocean and land surface. This extra machinery allows for new kinds of experiments to be done. Traditionally, in a GCM, one would impose atmospheric composition forcings by changing the concentrations of the species in the atmosphere e.g. the CO2 level could be increased, you could add more sulphate, or adjust the ozone in the stratosphere etc. However, with an ESM you can directly input the emissions (of all of the relevant precursors) and then see what ozone levels or aerosol concentrations you end up with. This allows you to ask more policy-relevant questions regarding the net effects of a particular sector’s emissions or the impact of a specific policy on climate forcing and air pollution.

Atmospheric chemistry is clearly a highly complex field. This makes it all the more strange and troubling that such a vast divide exists between debate between experts in the scientific community and debate within society at large.

That said, I suppose these situations aren’t really all that rare. Serious geologists and biologists continue to work out the minutiae of the history of present status of the Earth, at the same time as laypeople and self-styled ‘experts’ maintain debates about whether the world is 6,000 years old and whether all the creatures on it have existed since the beginning of time. By the same token, no matter how sophisticated scientific modeling of the climate becomes – and how much data accumulates demonstrating human-induced warming – there will still be people willing to baldly assert that climate change isn’t happening / is natural / isn’t a problem / is beneficial / is caused by sunspots, etc.

Wetlands and greenhouse gas emissions

A recent report from Wetlands International provides a global overview of greenhouse gas (GHG) emissions from wetlands. Neither their present state nor their total greenhouse gas holdings are comforting. Indonesia is the world’s most substantial emitter of GHGs from peat, with annual emissions of 500 million tonnes of carbon dioxide (CO2). That is about 2/3 of Canada’s total emissions. When it comes to stock, Canada leads the world with a troubling 155 billion tonnes of CO2 embedded in peat, enough to add 569 billion tonnes of CO2 to the atmosphere. In total, the 0.3% of the world’s land surface covered by drained peat already generates about 6% of global emissions.

This reinforces two points about climate change mitigation:

Firstly, we need to pay attention to land use changes as well as fossil fuel use, when it comes to cutting down the amount of GHGs humanity is adding to the atmosphere, eventually stabilizing at zero net emissions.
Secondly, if we create enough warming, there are huge stocks of carbon that could be released, pushing that process even further. Pushing the climate system to the point where positive feedbacks become dominant would commit us inescapably to significant additional warming, over and above that created through direct human actions.

While policies like a carbon tax to discourage emissions are a critical part of the solution, humanity needs to accept that our overall physical and biological impact on the planet is so large that we need to give serious consideration to how our collective policies and individuals choices are affecting the future of the climate. Recognizing the carbon intensity of drying marshland is a small but important part of that.

Why conservatives should love carbon taxes

The National Post – Canada’s right-leaning daily newspaper – has publicly stated that it believes climate change is real, and also that the current government has the right approach to dealing with it. In particular, it praises Environment Minister Jim Prentice for avoiding the “creation of state-managed “green economies” — socialism with a Gaian face.”

Whether such a creation is possible (and whether it would be desirable or not) are questions that can be set aside for a moment. The irony that seems to be paramount when it comes to the relationship between conservatives and climate change is how they stress a desire to interfere in markets and individual choices as little as possible, while rejecting the mechanism that would do that best: a carbon tax. A carbon tax doesn’t force anyone to drive a small car or, terrifying thought, forgo automobiles all together. It doesn’t force people to choose small pets, give up flying, or make other specific sacrifices. It also doesn’t rely upon the government deciding which energy technologies should succeed, whether that means renewables, nuclear, carbon capture and storage, or something else. It encourages low-carbon technological development in the most hands-off and market-friendly way possible.

All a carbon tax does is take the price imposed on strangers by greenhouse gas emissions and makes it ‘internal’ to the decision-making of individuals and other economic actors throughout society. It comes the closest to retaining the libertarian ideal in a world where interconnectedness forces us to take into consideration the consequences our actions will have on others. I have talked before about the irony of how laissez faire climate policies will inevitably fail and force governments to take employ more coercive measures. That outcome can only be avoided by sending a clear price signal on greenhouse gas emissions, and doing so early and at a meaningful level. Indeed, a carbon tax can be said to be a way of protecting property rights, given that it reduces the degree to which emitters will harm the property and prosperity of other people around the world.

It should be noted that the important policy change here is to put a price on carbon emissions, to represent the harm they cause to other people. The establishment of such a price is more important than the precise mechanism through which it is done, whether that is a carbon tax or a cap-and-trade system in which 100% of the permits are sold at auction. The choice of instrument is less important than moving quickly to put a price on carbon in one way or another.

It is an open question whether conservatives will realize the extent to which they are undermining their own aims and ideals through opposition to carbon pricing. Part of that is the paleoconservative stance that climate change isn’t happening, that it is benign, that it is inevitable, etc. Among conservatives with enough basic awareness about the world to know that those arguments have been discredited, we should hope that support begins to grow for the idea of dealing with the climate problem in the way that involves the least expansion of the state and the least infringement on liberty: a carbon tax.

While there may well be cause for accompanying such a tax with other regulations – such as a ban on coal power – at least gaining conservative support for some kind of carbon action would change the tone of the debate. We would finally stop pretending that we can ignore climate change indefinitely while the economy keeps ticking on just fine, and begin to appreciate and implement the steps required to build a low-carbon future.

Arctic sea ice, in the midst of re-freezing

While 2007 retains the record for the lowest observed mimumum summer Arctic sea ice extent, the level right now is the lowest ever observed for this time of year:

The US National Snow and Ice Data Centre explains the situation with reference to strong winds: “the growth rate slowed for a time in early October, coinciding with strong winds from the south over central Siberia. The winds helped prevent ice from forming along the Siberian coast. At the end of the month, extensive areas of open water regions were still present in the northernmost North Atlantic, and north of Alaska. The ice edge was north of both Svalbard and Franz Josef Land.”

The year-on-year trend, going back more than 30 years, shows that fall ice has been progressively less extensive. Note that, at Canada’s northernmost permanent settlement nautical polar night conditions exist from late November to mid-January. During this time, “no trace of light can be seen anywhere but the sky is not completely dark at midday.” Further north, where the middle of the Arctic icecap is, this period of darkness extends even longer.

Climate science and policy-making

I wrote the following to serve as a one-page introduction, laying out some of the key items for consideration and listing some of the most accessible and reputable sources of information about climate change. For more information on specific subjects, see my climate change index.

The key elements of the general climate science and policy consensus are:

On average, the planet is warming.
Most of this is because of human emissions of greenhouse gases.
Continued warming would be harmful, and perhaps very risky when it comes to human welfare and prosperity. Anticipated changes include melting glaciers and polar ice, more extreme precipitation events, agricultural impacts, wildfires, heat waves, increased incidence of some infectious diseases, sea level rise, ocean acidification, and increased hurricane intensity.
By most accounts, the cost of mitigation is less than the cost of adaptation. Some anticipated changes may overwhelm the capacity of human and natural systems to adapt.

While there is a public perception that there is a lot of scientific disagreement about the fundamentals of climate science, this really is not the case. Back in 2004, a survey of peer-reviewed work on climate science demonstrated this. There is also a notable joint statement from the national science academies of the G8, Brazil, China, South Africa, and India.

To borrow a phrase from William Whewell, there is a ‘consilience of evidence’ when it comes to the science of climate change: multiple, independent lines of evidence converging on a single coherent account. These forms of evidence are both observational (temperature records, ice core samples, etc) and theoretical (thermodynamics, atmospheric physics, etc). Together, these lines of evidence provide a conceptual and scientific backing to the theory of climate change caused by human greenhouse gas emissions that is simply absent for alternative theories, such as that there is no change or that the change is caused by something different.

Readers who are dubious about the validity of mainstream climate science, or unsure of what to think, my page for waverers may be useful.

1) Climatic science and history

There are some good primers available from reputable organizations online. For instance, the United Kingdom’s Met Office has a quick guide.

The Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) is the most authoritative review of the scientific work that has been done on climate change. The summary for policy-makers for the synthesis report is available online.

For detailed information on the physical science of climate change, the technical summary of the IPCC’s Working Group I report is a good resource. Unlike the summaries for policy-makers, which are vetted through a quasi-political process, the technical summaries are prepared exclusively by scientists.

For Canadians who want to read one book about climate science and policy, I recommend University of Victoria Professor Andrew Weaver’s book: Keeping Our Cool: Canada in a Warming World.

For those looking for a concise history of the entire development of climatic science, starting in the late 1800s, I very much recommend Spencer Weart’s The Discovery of Global Warming. In addition to the book form, it is available free online.

For a more specific history of what we have learned about climate from ice core samples, see Richard Alley’s The Two Mile Time Machine. For an excellent (though somewhat technical) discussion of the relationships between the carbon cycle and biological organisms, see Oliver Morton’s Eating the Sun.

2) Climate change mitigation

Ultimately, the only way to keep the concentration of greenhouse gases in the atmosphere constant is to reach the point where humanity has zero net emissions. Getting there fundamentally requires two things: the shifting of the energy basis of the global economy to low- and then zero-carbon sources, and the stabilization of the biosphere through actions like ending net deforestation. It is widely accepted that setting a sufficiently high price for greenhouse gas emissions is a vital way to drive mitigation actions.

Three excellent books that evaluate options for moving to a low-carbon economy are:

George Monbiot’s Heat: How to Stop the Planet from Burning (in which he considers how the UK could achieve truly dramatic rapid reductions in greenhouse gas emissions)
Joseph Romm’s Hell and High Water (focused on the United States)
David Mackay’s Sustainable Energy Without the Hot Air (in which he evaluates renewable and efficiency options from first principles, but in a very accessible way – available free online)
Michael Mann’s Dire Predictions: Understanding Global Warming (accessible summary of the IPCC reports)

On the costs of climate change mitigation, the most comprehensive work is probably that which has been done by Nicholas Stern, beginning with the Stern Review. The review’s executive summary is also accessible online. More recently, he has argued that the costs of inaction are even more significant than those projected at that time.

On the political and ethical side of things, the best short summary may be Stephen Gardiner’s article “Ethics and Global Climate Change,” published in Ethics. Volume 114 (2004), p.555-600. One key idea related to international equity and climate change mitigation is contraction and convergence: an arrangement in which the emissions from all states eventually fall to zero, but where the per-capita emissions of developed and developing states also converge over time.

My fantasy climate change policy combines a moratorium on coal and unconventional fossil fuels with a hard cap on emissions.

3) Other major climate change issues

Other areas relevant to climate change policy-making include:

Abrupt and runaway climate change scenarios
Adaptation to climate change
Carbon sinks (physical, such as the oceans, biological, such as the forests, and geological, such as rocks that erode and form carbonates)
Economics (carbon pricing, risk management, etc)
Emission pathways (and their international breakdown)
Equity issues (historical responsibility, climate change and development, etc)
Global politics and international law
Planning and design (cities, buildings, etc)
Science (climatic equilibria, models and projections, etc)
Sociological and philosophical issues (ethics, communication, political theory, etc)
Targets (stabilization concentrations, temperature change, etc)
Technologies (renewable energy, transport, nuclear, efficiency, etc)

I can recommend resources in all of these areas, if someone has a particular interest.

4) Good sources of climate related news

Probably the best scientific climate change blog is RealClimate.

Good responses to climate ‘skeptic’ arguments can be found in the How to Talk to a Climate Skeptic series. I also keep track of my own arguments with climate change deniers.

Climate coverage in mainstream media sources is often inconsistent in quality. The BBC and The Economist often publish good information, but also sometimes include incorrect or misleading information.

5) A few key graphics

This ice core record of carbon dioxide concentrations illustrates one major reason why we should be more concerned about human-induced climate change than about natural variation. Our use of fossil fuels is generating a spike in greenhouse gas concentrations that is set to rise far above anything in the last 650,000 years, at least.

The above shows how observed warming is inconsistent with climate models that do not incorporate human greenhouse gas emissions, but consistent with those that do.

The wheel on the right depicts researchers’ estimation of the range of probability of potential global temperature change over the next 100 years if no policy change is enacted on curbing greenhouse gas emissions. The wheel on the left assumes that aggressive policy is enacted. (Credit: Image courtesy / MIT Joint Program on the Science and Policy of Global Change)

I would be delighted to answer and questions, or suggest further resources in other areas of interest.

Last updated: 23 January 2012

Octane and gasoline engines

I am learning a lot about hydrocarbon fuels from Morgan Downey’s Oil 101. For instance, that the common understanding of the phrase ‘high octane’ is somewhat misleading. In the context of gasoline-powered internal combustion engines, such as those in cars, the octane rating of a fuel refers to how much it can be compressed along with air before it will spontaneously ignite. In these engines, fuel and air are mixed together and compressed in a cylinder. They are then ignited at a precisely controlled time by a spark plug. Cases where the mixture explodes before then are called ‘engine knock’ and are damaging. As such, engines are designed to use fuel above a certain octane number, in order to be confident that knocking will not occur.

When it comes to choosing fuel to buy, this means it is appropriate to use a grade with an octane rating as high as cited in the operating manual of a vehicle. Going higher, however, may be a waste of money for two independent reasons. Firstly, higher octane fuels are more expensive because they cost more for refineries to produce. Unless your engine is tuned to take advantage of the extra opportunity for compression, no additional power will be generated. Secondly, higher octane fuels often contain less energy per litre, because the hydrocarbons that comprise them have less energy in their chemical bonds. As such, a litre of more-expensive high octane fuel likely will not take a vehicle as far as a cheaper litre of adequate-octane fuel.

Octane numbers are assigned based on how a fuel compares to two specific hydrocarbons: isooctane (which is hard to ignite by compression) and n-heptane (which is easy to ignite that way). 90 octane fuel is thus as resistant to pressure-induced ignition as a mixture of 90% isooctane and 10% n-heptane. Some fuels are even better at resisting pressure-induced ignition than isooctane, and can therefore have octane numbers over 100.

In diesel engines, this is reversed. They do not have spark plugs and rely upon the ability of fuel to ignite spontaneously in the presence of pressurized air. In diesel, the cetane number refers to the propensity of fuel to autoignite on compression. Here, a higher number is more desirable.

One other thing I didn’t know about liquid transport fuels is that the fuel used by piston-driven aircraft, such as small propeller planes, still uses tetra ethyl lead to increase its octane rating. This practice has been discontinued in cars both because it interferes with catalytic converters and because it was massively increasing human exposure to lead – a known cause of brain damage. In aviation gasoline, tetra ethyl lead is used instead of alcohols to boost octane. This is because alcohol-blended fuels are less energy dense, more prone to vapour lock, liable to separate at low temperatures, as vulnerable to corrosion. Such aircraft are a relatively tiny share of the total market for hydrocarbon fuels; still, it isn’t particularly comforting to know that they continuously disperse lead on whatever is below them.

Fighting oil sands emissions by burning natural gas?

According to Morgan Downey’s Oil 101, it actually takes more energy to produce a barrel of synthetic crude oil from the oil sands than the barrel of crude contains. Most of that extra energy comes from natural gas. It is worth paying that energy cost because crude oil is a valuable product that can be turned into gasoline, kerosene, etc, whereas unprocessed bitumen laden sand has no value. Note that even more energy is required to run the refineries that turn synthetic crude into usable fuels.

As a result of this, the economic viability of the oil sands depends on natural gas remaining cheap enough for synthetic crude to compete. As such, it is arguably the case the promoting natural gas as a fuel for vehicles and electricity generation is a smart climatic move. It is a relatively clean fuel in those applications, and using it in that way might keep a larger share of it from being used to upgrade bitumen – thus leaving the carbon contained therein safely buried.

In Scenario A (cheap gas), a lot of Canada’s northern natural gas goes towards liquefying and upgrading bitumen, thus liberating the carbon it contains into the atmosphere, both during upgrading and refining processes and when the resultant fuels are burned.

In Scenario B (expensive gas), the natural gas is used for higher-value purposes like electricity generation, and more of the carbon in the bitumen never ends up in the atmosphere. Other forms of environmental damage associated with the oil sands – including air and water pollution, habitat destruction, etc – are also lessened.