January 2008 – Page 2 – a sibilant intake of breath

But why drives on that ship so fast / Without or wave or wind?

A company called SkySails is hoping to reduce fuel usage by large shipping vessels by supplementing their fossil fuel engines with wind power. They estimate that a kite of 160 square metres could, when tethered to a ship, reduce fuel usage by 20%. The company has a video explaining the idea.

It would be very interesting to know (a) what proportion of a time such a system could be used during real-world shipping and (b) how long it would take to pay back the total cost of the system through lower fuel bills.

Earth Flotilla

The 1997 and 1998 LIFEboat Flotillas were exceptional undertakings that I was privileged to participate in. Organized by Leadership Initiative for Earth, each centred around a week-long sailing experience in the Gulf Islands of British Columbia, intended to help make young people more aware of environmental issues and better connected with those similarly interested.

In March of this year, a smaller but similar expedition is taking place, organized by the World Wildlife Fund, in cooperation with some of the people involved in the original flotillas. Applicants must be residents of British Columbia between 13 and 17. They must be interested in environmental issues and willing to put in the time required.

As someone lucky enough to do something similar in the past, I recommend the opportunity wholeheartedly. If any readers of this blog match the description – or know people who do – application information is online.

[Update: 11 February 2008] I am pleased to report that Tristan’s brother will be participating in the Earth Flotilla, and because his family found out about it from this site, no less.

Radiation types and units

Types of radiation

Radiation is categorized in several different ways. One is on the basis of energy levels: ionizing radiation is sufficiently energetic that it can cause an atom or molecule to be stripped of an electron, turning it into an ion. This depends on the energy level of the individual particles or waves and has nothing to do with the total number of them. Non-ionizing radiation is simply that which doesn’t have enough energy to liberate an electron.

Another way to classify radiation is in terms of whether it is electromagnetic (consisting of photons) or particle radiation. There are three types of particle radiation: alpha decay, based on the emission of two protons and neutrons bound together in a helium nucleus, beta decay, wherein the particle emitted is an electron, and neutron radiation, where atoms release neutrons. Alpha particles are not generally very dangerous, because they are unable to penetrate much of substance. Even a few centimetres of air can have a strong protective effect. That said, ingestion can still be highly dangerous. The Polonium-210 that killed Alexander Litvinenko is an alpha emitter. Beta particles can usually be shielded from using a few milimetres of lead. Neutron radiation is unusual insofar as it is capable of producing radioactivity in the atoms it encounters. Shielding consists of a large mass of hydrogen rich materials.

Electromagnetic radiation with sufficient energy to be ionizing cosists of x-rays and gamma rays. Both consist of high-energy photons (those with short wavelengths), with gamma rays having shorter wavelengths than x-rays (10^(-12)m rather than 10^(-10)m). Shielding, especially for gamma rays, must be dense and fairly extensive.

Measuring radiation

Radiation is also measured in a variety of ways: important ones being Roentgens, rads, rems (Roentgen equivalent in man), Curies, Becquerels, and Sieverts.

Becquerels are a unit of radioactive decay based only on the number of decays per second. A Curie is equal to 3.7 x 10^10 Becquerels, and is approximately equivalent to the activity of 1 gram of Radium isotope. These units reflect the number of emissions only – not their physical or biological effects.

A Roentgen is a measure of ionizing radiation based on the ratio between charge and unit mass. Rads are a largely obselete unit of radiation dose, equal to 100 ergs of energy being absorbed by one gram of matter. Rems are the product of the number of Roentgens absorbed, multiplied by the biological efficiency of the radiation. Rems are also considered highly dated as a measure of radiation. 450 rems is an approximate lethal dose (LD50), for those who do not receive prompt treatment.

Sieverts are the recommended replacemend, “found by multiplying the absorbed dose, in grays, by a dimensionless “quality factor” Q, dependent upon radiation type, and by another dimensionless factor N, dependent on all other pertinent factors.” The LD50 for ionizing radiation is about 5 grays or about 3-5 Sieverts. If the biological efficiency used to calculate rems equals one, one Sievert is 100 rems.

Water and nuclear power

Once the heat generated by nuclear fission has finished spinning the turbines in nuclear power plants, it must somehow be dissipated into the wider environment. Almost invariably, this is done using large amounts of water drawn from nearby rivers and lakes. Now, for plants located in drought-struck regions such as the southeast United States, possible water scarcity threatens to shut down plants, forcing the costly purchase of energy from other jurisdictions.

The Associated Press estimates that 24 of America’s 104 nuclear reactors are located in areas currently experiencing severe drought. On reactor outside Raleigh, North Carolina will need to be shut down if water levels in the lake fall by another 3 1/2 feet. In total, nuclear power provides about 10% of the American supply of electricity. All but two American nuclear plants are cooled using water from lakes and rivers. Some plants evaporate large amounts of water from cooling towers, while others are designed to return the warmed water to the body that originally provided it. Immersing collection pipes at lower levels risks being costly, as well as increasing problems from sediment intake into the cooling system.

All this demonstrates the degree to which many forms of low-carbon energy generation are themselves vulnerable to climate change. Concern about water being a limiting factor in energy production is already acute in Australia. Dams face risks from both drought and the loss of snowpack in mountain ranges (leading to too much water at some times of year and not enough at others). Even wind turbines may be vulnerable to changes in dominant patterns of air circulation. Designing future infrastructure with possible climate changes in mind is essential, if we are not to find ourselves with a lot of expensive hardware rendered useless by changed conditions.

Mastercard and RFID

I got a replacement Mastercard in the mail today and was slightly surprised to learn that it has an embedded radio frequency identification (RFID) tag in it. The idea is that it will let merchants bill you card by having you put it near a reader, rather than swipe it though a magnetic strip reader. The existence of the RFID tag does raise a couple of issues, however.

First, it has been shown that such tags can be activated using inexpensive directional transmitters from relatively long ranges. The way they work is by using the energy in the incoming radio signal to power the circuitry that produces a response. I don’t know if the tag in my card simply has a unique identifier, or whether it actually performs a challenge-response authentication. Either way, it is likely that the presence of the card, and the fact that it is a Mastercard, can be determined at a distance of several tens of metres at least, using information and equipment fairly easily acquired.

Secondly, I don’t know about the liability associated with such cards. I know that if I lose my Mastercard and report it promptly, I am only liable or $50 at the most. I am not sure about a situation where somebody clones the RFID tag and uses it to make purchases.

Overall, I see little value in contact-free payment systems. I would rather have a traditional card without new features and vulnerabilities. Unfotunately, Mastercard says that RFID-free cards are no longer available.

You must do the heaviest / So many shall do none

When it comes to reducing personal environmental impact in any sphere (pollution, climate change, resource depletion, etc), there comes a point where each individual says: “That is too great a sacrifice.” Some people would refuse to give up incandescent bulbs; some, eating meat; some, driving their cars; some, flying in jets. The question arises of what to do when there is a fundamental conflict between an ethical requirement and a person’s will. In the modern world, this applies perhaps most harshly to air travel.

We know that very substantial emissions are associated with flying. We also know that substantial emissions will definitely cause human suffering and death in the future. One flight emits significantly more than a single person can sustainably emit in a year. Every year emissions are above sustainable levels, the concentration of greenhouse gases rises; each year in which that happens, the mean energy absorbed by the planet increases. At some point in the future, it is inevitable that this process would cause massive harm to human beings and non-human living things. It is also plausible that positive feedbacks could create abrupt or runaway climate change, either of which could cause human extinction or the end of humanity as a species with civilization. In the face of that, it is difficult to say that flying isn’t morally wrong.

At the same time, it is impossible for most people to say it is. Partly, this is because of a failure of imagination. They cannot imagine a world where people don’t fly. Mostly, though, it is reflective of the powerful kind of denial that lets people continue to live as they do, even when convincing evidence of the wrongness of their behaviour is revealed. Rationalizations are myriad: (a) Why should I stop when others will just continue? (b) There has to be a balance between acting ethically and getting what I want. Neither of these has any ethical strength in the face of a known and significant wrong. At the same time, it is implausible that people will abandon their self-deception or that external forces will constrain their behaviour effectively. If that is true, our future really isn’t in our hands. We are slaves to fate, in terms of what technological innovation might bring and in terms of how sensitive the climate really is to greenhouse gasses.

Comprehensible art

Perhaps my favourite thing about Vladimir Nabokov is how he never sacrifices clarity for the impression of brilliance. So many great modern authors seem to take delight in baffling their readers, whether with torturous sentences, incomprehensible plots, or surrealism. James Joyce is especially guilty, but hardly alone, in his use of such approaches. While such writing can push the boundaries of language, it is likely to try one’s patience as well. As such, it is especially pleasant to see genius expressed in a straightforward form: excellence in a fairly traditional format.

It’s rather like the different kinds of modern art. There may be some profound idea in the mind of the artist who has splattered a crumpled canvas with Burger King condiments, but I have a lot more respect for the one who made the elegant sculpture in wood or marble or bronze.

Fishing should never be subsidized

The economic case for government subsidies can be made in one of two ways. The first is the argument based on externalities: the idea being that one person’s behaviour creates benefits for others, but that those others do not compensate the actor. An example might be a landowner who refrains from cutting down trees uphill from rivers. All river users benefit from the flood control and lack of silt. In this case, it might make sense for the government to pay the landowner to save the trees – in providing the subsidy, the government encourages a more socially optimal behaviour. This justification doesn’t work for fisheries. Fisheries are a common property resource and, as such, tend towards over-exploitation. Having fishers catch more does not provide anyone else with benefits; indeed, it harms the ability of everyone else to use marine resources. Subsidizing fishing pushes fishers to continue catching fish even beyond the point where it would normally be unprofitable, leading to further depletion.

The second argument for subsidies is the ‘infant industries’ argument. The idea here is that it can take a while for a new business to reach the level of existing businesses in the field. A brand new textile industry in an African state may not initially be able to produce goods at a cost and level of quality competitive with existing industries in Asia. In such cases, you can justify a temporary program of subsidy, intended to get the industry running. Once again, this doesn’t apply to fisheries. If anything, there is too much fishing capacity in the states that subsidize heavily (North America, Europe, and Japan). Excess fishing capacity is being exported into developing states, depleting the resources there.

The one form of subsidy that can be justified in relation to the fishing industry is subsidized training to get out of it. We can recognize that fishers are having an increasingly difficult time making a living, while also recognizing that subsidizing their fuel or equipment will just batter fish stocks further. The solution is to help people to transition into other industries where they can sustain themselves without depleting pools of resources common to everyone. It is always hard for politicians to say that an industry should be smaller, or should not exist at all, but, in the case of fisheries, that is probably the only position that makes economic and ecological sense.

Good information on space militarization

This briefing on the militarization of space is very interesting. It is especially good insofar as it describes the special situation of the United States in relation to space and warfare, the consequences of the recent Chinese test of an anti-satellite missile, and some of the practicalities involved in tracking space debris and keeping satellites away from it.

Cycling in the freezer

Every time I descend into my unheated basement to do laundry, I note the presence of my shiny hybrid bike over in the corner. Partly on the basis of a tumble early in the season, I have generally been of the opinion that winter cycling in Ottawa is simply too treacherous. Even on bright sunny days, cycling through Centretown is a big pain, likely to involve dangerous confrontations with drivers largely unaware of cyclists near them. In the winter, when bike paths go unplowed and unused, such interactions would necessarily be more frequent, as well as more perilous.

That said, there are some who brave the elements and endure as cycle commuters throughout the bitter winter. While I doubt I will ever acquire their level of commitment, I would consider getting studded tyres and other winter gear if it seemed highly likely that I was going to spend more than a few winters in these conditions.