Archive for October, 2006

New Coal Power Plants in the US

Monday, October 30th, 2006

WeSupportLee provides an excellent look at a variety of energy topics.

One of these, new coal plants, generates disproportionate yawns in the public . Yes, there are protests, but these protests are not proportionate to the harm done by coal. (Part of the reason I think so is because we in California build our coal plants to the east, so they pollute others. Hence, little local discussion. Here CA lists much of its coal power under Energy Imports: Pacific Southwest; here that figure is included, check out the coal use in your state.)

Fortunately, new California regulations and legislation are discouraging the addition of coal power. California Public Utility Commission requires a “Carbon Adder” for planning future power plants; utilities must assume that carbon cap and trade or carbon taxes are being applied and will be increased. Utilities assume a price of $8/ton C in 2005, and increase the assumed price 5%/year. Otherwise, utilities might be making business plans based on an unlikely scenario, that greenhouse gases will not be regulated, and that coal power will continue to be cheap. AB 32 requires California greenhouse gas emissions in 2020 to decrease to 1990 levels.

WeSupportLee looks at less positive decisions: coal plans for Kansas (2,100 MW, eek, approval likely) and for Texas (and includes links to other discussions on TX plans).

The recent Stern report says,

The effects of our actions now on future changes in the climate have long lead times.What we do now can have only a limited effect on the climate over the next 40 or 50 years. On the other hand what we do in the next 10 or 20 years can have a profound effect on the climate in the second half of this century and in the next.

Countries with huge coal supplies will insist on using them. However we must require no new coal plants without carbon capture and storage technologies. Basically, instead of using air, a coal power plant uses a different (and much less polluting) design, and oxygen instead of air, producing only 1/5 as much waste gas. The waste gas is then injected into permanent storage, in a coal mine or oil well.

The less polluting part is important: coal particulates alone kill 30,000 Americans each year from heart and respiratory disease. Pennsylvania has the largest number of coal deaths per year (2,250), and Kentucky (1,000) the largest per capita coal deaths. See the effect of coal power on your state in the appendix. It is not good of us to ignore this kind of pollution: excepting second hand smoke, fossil fuel particulates kill more Americans each year than all other pollutants combined.

There is an additional benefit of increasing the price of electricity, a lot. This encourages much more rapid increases in energy efficiency, doing the same with less energy.

The current path is immoral, and not economically prudent, and decisions being made in Texas and Kansas to increase coal use will have enormous negative implications for the rest of the United States and the rest of the world.

Object. Let your legislators know that you would like to see greenhouse gas cap and trade policies enacted immediately. These should be significant enough to make current designs for coal power plant unfeasible. Additionally, pilot tests must be done to give more information and to minimize problems. The current Department of Energy policies lack a sense of urgency.

Object. Currently few Americans list the environment as an important reason for our vote, and our legislators are acting accordingly.

Nuclear Proliferation—International Treaties

Saturday, October 28th, 2006

More from David Bodansky’s Nuclear Energy (second edition), again, read it yourself for more details. Recommended readings include Richard Garwin and Georges Charpak’s Megawatts and Megatons, and Robert Mozley’s The Politics and Technology of Nuclear Proliferation.

Eisenhower began the Atoms for Peace program in 1953. The first successful international agreement led to the creation of the International Atomic Energy Agency (IAEA) in 1957. The IAEA reports to the United Nations but is not part of the UN. All countries with nuclear activities, excepting North Korea, which withdrew in 1994, are among the 136 members.

The Non-Proliferation Treaty (NPT) was next, going into force in 1970. Its motivating purposes were to

• Prevent the wider dissemination of nuclear weapons,
• Make peaceful applications of nuclear technology widely available.
• Achieve cessation of the nuclear arms race and move toward nuclear disarmament.
• Seek to achieve discontinuance of test explosions of test explosions of nuclear weapons.

There has always been an asymmetry between nuclear-weapon states (NWS, those with nuclear weapons before 1967: China, France, the USSR, the United Kingdom, and the United States) and non-nuclear-weapon states. A NWS is obligated not to aid weapons development in a non-NWS. Each non-NWS is committed to not receive or build nuclear weapons, and to accept safeguards against the diversion of nuclear activities from peaceful to weapons purposes. A conference was to be held in 1995, to determine whether to continue the treaty indefinitely, or to extend it for additional purposes.

Inducements for the non-NWS include the commitment by NWS to “pursue negotiations in good faith on effective measures relating to the cessation of the nuclear arms race at an early date and to nuclear disarmament”. The parties also agree to share fully the peaceful uses of nuclear energy. The most important holdouts are India, Israel, and Pakistan. North Korea withdrew in 2003.

The NPT was extended indefinitely in 1995, though many of the non-NWSs felt that nuclear disarmament should be more rapid, and Arab states objected to Israel’s absence. Among 20 principles and objectives adopted were these:

• A call for a comprehensive test ban treaty by 1996 and a universal ban on production of fissile materials for weapons. NWSs were called to make “systematic and progressive efforts to reduce nuclear weapons globally” with an eventual goal of eliminating them.
• A call to encourage “the development of nuclear-weapon-free zones, especially in regions of tension, such as in the Middle East”.
• An affirmation that the peaceful use of nuclear energy is an “inalienable right of all parties to the treaty”.

An every 5-year review to monitor progress in 2000 showed continuing tensions between NWSs and non-NWSs, but also pointed a finger at countries which had not adhered to the treaty: Cuba, India, Israel, and Pakistan for not signing, and India and Pakistan for weapons test. The NWSs agreed to an “unequivocal undertaking” toward “total elimination of their nuclear arsenals”, but without a deadline or timetable.

Comprehensive Nuclear Test Ban Treaty

The CTBT, adopted by the UN in 1996, commits the parties to not carry out nuclear weapon test explosions or any other nuclear explosion. By the end of 2003, it was signed by all the NWSs and 170 out of 193 states, and ratified by 108. It will only go into effect if all 44 states with nuclear power or research reactors (Annex 2 states) sign and ratify the treaty. India, North Korea, and Pakistan have not signed. Another nine of these 44 states have not ratified it, including the US.

While it would be more effective if it had been ratified by all Annex 2 states, it may serve to inhibit some countries, including the US. The CTBT led to a large network of seismic observation points; these detected the 1998 nuclear weapons tests in India and Pakistan.

The NPT and CTBT do not command the universal adherence that a fully effective nonproliferation regime should have. Nonetheless, they are taken seriously.

One problem can be lack of a strong response due to sympathy for the country arming, such as India threatened by China and Pakistan or Pakistan threatened by India or Israel threatened by the Arab world. Some countries are unwilling to condemn, or may even help, allies: the USSR provided political and technical help to India, and the US has tolerated Pakistani and Israeli nuclear weapons programs.

There have been NPT failures with signatories as well: Iraq in 1991, though it had a full safeguards agreement with the IAEA. However, NPT provided the legal basis after the first Iraq war for weapons inspections.

Forms of Proliferation

Proliferation includes increases in the number of nuclear weapons, or the means of making them, whether the country already has weapons or not.

These range from obtaining technical advice to obtaining weapons-grade uranium or plutonium. The barrier against proliferation is substantially lowered if a country possesses facilities for enriching uranium or reprocessing spent fuel to extract plutonium, and the development of such facilities is taken as a danger signal, however much the country involved professes a peaceful intent.

Proliferation includes, but is not limited to, the following:

• Increases in the number of effectiveness of weapons in a state with nuclear weapons.
• Public transfer of weapons to another state, though the example transfer of weapons from Ukraine, Belarus, and Kazakhstan reduced proliferation dangers.
• A state with advanced nuclear capabilities openly working on obtaining a nuclear weapons program, perhaps Japan reacting to North Korea.
• Utilizing equipment for ostensibly peaceful purposes to facilitate weapons development (India, Israel, and North Korea)
• Transferring weapons material from states with weapons to states without, with the aid of a government or dissident officials, or by theft. The former Soviet Union and Pakistan have been thought to be particularly vulnerable as sources for such transfers.
• Transfer of technology, including designs and specialized equipment, by states, private companies, or individuals. Pakistan shared designs and equipment for centrifuges with Iran, Libya, and North Korea. China may have forwarded instructions on bomb construction through Pakistan.
• Purchase of theft of a weapon or fissile material by subnational groups or individual terrorists.

The original nuclear weapons concern was use of nuclear weapons by one of the original NWSs. Now concern has shifted to the spread of nuclear weapons to other states and terrorists. Moreover, numerous reports of small-scale nuclear materials thefts may indicate other, undiscovered thefts.

It is unlikely that any attempt to classify and rank the specific threats can be fully satisfactory. Detailed information on nuclear technology is now held by many countries, commercial enterprises, and individual scientists, and the industrial capability to manufacture specialized components is widespread. The prospect remains that additional countries or subnational groups may seek to obtain weapons. Given the variety of avenues for obtaining fissile uranium or plutonium, the many sources of technical knowledge and equipment, and the potentially large array of aspirants, nuclear weapons proliferation may appear in unexpected places and forms.

How many nuclear weapons exist? As of 2002 the US had 10,600 warheads, down from 31,700 in 1966. Russia had 8,600, down from 40,700 in 1986. China had 400, down from 435 in 1991. France had 350, down from 540 in 1991. The UK had 200, down from 350 in 1975. Among non-signatories of the NPT, in 1999, India was thought to have 30 weapons, Israel 100, Pakistan 40, and North Korea 1 – 2.

Each of the NWSs achieved nuclear power after nuclear weapons. The United States produced nuclear power in 1957 (weapon 1945), the former USSR in 1958 (weapon 1949), the UK in 1956 (weapon 1952), France in 1964 (weapon in 1960), and China in 1992 (weapon in 1964).

The next post will look in some detail at the history of weapons programs in other countries.

Also in this series
Part 1 Nuclear Bombs, Nuclear Energy, and Terrorism
Part 2 Today’s Bombs, Making a Bomb
Part 3 Making Bombs from Nuclear Waste
Part 4 Terrorist Targets
Part 6 The Bomb Spreads
Part 7 Nuclear Power and the Weapons Threat
Part 8 Wrapup on Nuclear Power Series

CA Propositions 1A and 1B

Friday, October 27th, 2006

Proposition 1A, another constitutional amendment, would require that sales tax on gasoline and other fuels go to transportation needs. Proposition 1B is another bond issue—“improvements in every corner of the state without raising taxes.” Italics in the ballot measure summary. Typical bond measure in California, projects are chosen partly for geography and we are told that we can get bonds today without taxes tomorrow. This one advocates spending $39 million over 30 years, $19 billion interest on a principal of $20 billion.

According to the Official Voter Information Guide, the state 18 cent/gallon tax on gasoline and diesel generates $3.4 billion annually, and sales tax on fuels brings in another $2 billion per year. There are also weight fees on commercial vehicles. Since 1990, $5 billion in general obligation bonds have helped fund transportation.

There is another path. Not only could drivers fund all transportation costs without resorting to state bonds, but higher fuel taxes could displace inevitable increases in general taxes. Some believe all sales tax should go the general fund – what makes sales tax on fuels so special that it should be spent in just one way?

Am I wrong? Do you have another take?

Terrorist Targets

Friday, October 27th, 2006

More from David Bodansky’s Nuclear Energy (second edition), again, check out this readable book for more information.

There are any number of targets and tools terrorists, people targeting civilians, might consider. A partial list:

• places where people assemble, such as theaters, sports stadia, and cruise ships.
• choke points in transportation routes, such as bridges and tunnels.
• symbolic targets, such as the Statue of Liberty.
• national energy carriers: electric transmission lines, gas pipelines, and oil tankers [and refineries].
• food and water supplies: introducing poisons into food and water supplies on a large scale or in a seemingly random local manner.
• weapons of mass destruction: introducing biological, chemical, or nuclear materials into the environment quietly or using violent explosions. [This includes direct attacks on chemical plants.] The casualties might range from tens to tens of thousands, and conceivably much more.

Given the options, it is not clear how high a place nuclear terrorism occupies in planning by terrorist groups.

The following will consider threats involving nuclear weapons and materials, not because these are the most likely or most dangerous terrorist targets, but because they are important, and because there is widespread interest.

In the US, the threats will be of three kinds:

• nuclear bombs,
• radiological dispersion devices or dirty bombs, radioactive material spread into the environment by a conventional bomb, and
• attacks on nuclear power plants, either the reactors or the spent fuel.

A bomb could be stolen or built abroad, and delivered intact or in pieces, or could be constructed where it will be used. Drug smuggling gives an indication as to how easy getting uranium or plutonium (neither of which is very radioactive) into the country. According to a report issued jointly by the Project on Managing the Atom (Harvard’s Kennedy School of Government) and by the Nuclear Threat Initiative, a 10-kt bomb would

create a circle of near-total destruction perhaps 2 miles in diameter. Even a [one thousand ton] “fizzle”from a badly executed terrorist bomb would have a diameter of destruction nearly half as big. If parked at the site of the World Trade Center, such a truck-bomb would level every building in the Wall Street financial area and destroy much of lower Manhattan.

Terrorists could steal or receive as a gift a government-built bomb. There is not much worry about bombs in the US, Britain, China, France, and Israel because these weapons are well protected, and except for the US, inventories are small. The level of threat is “medium” for Pakistan and India, with their unstable political situation, and for Russia, with its large inventory and poor inventory controls. See Making the Nation Safer for more on this subject.

A moderately large and technically capable group that can’t get a bomb could make one if they could obtain enough fissionable material by theft or gift.

The Center for International Security and Cooperation compiles information on illicit traffic in nuclear materials. There are worries that undetected thefts have occurred, because so many incidents are known about: 3 kg of weapons grade uranium offered for sale in St. Petersburg in 1994, 2 kg disappearing in the Republic of Georgia, a fuel rod containing 0.19 kg enriched to 19.9% which the Italian mafia intended for an undisclosed buyer in the Middle East. The detected traffic in material from the former Soviet Union began westward into Europe, then switched to southward (Iraq, Iran, and Afghanistan) during 1999 – 2000.

To reduce the availability of nuclear weapons material:

• Ensure that weapons and weapons-grade material are protected in all countries with them, particularly the countries with the most, the US and Russia.
• Secure stocks of plutonium removed from dismantled weapons (intended for Yucca Mountain in the US and commercial reactors in Russia).
• dilute stocks of highly enriched uranium by diluting with natural or depleted uranium, and then using in nuclear power plants. [See WeSupportLee for more on this.]
• Improve security or remove plutonium and enriched uranium from vulnerable facilities.

Bomb delivery

For the immediate future, it seems unlikely that any terrorist group will have the missile capabilities to deliver a bomb to the United States. Further, if the missile were sent from a land base, its point of origin would likely become known, giving the potential host country a powerful incentive to prevent the activity.

[On the other hand, Castro was said not to worry about this problem during the Cuban missile crisis.]

Smuggling the bomb in should not be too hard, because bombs emit little radiation that would trigger a detection device. Methods to detect devices include the following:
• direct detection of radiation, primarily gamma rays or neutrons,
• radiography, passing the container or vehicle through a machine which makes elements with high atomic numbers (uranium or plutonium) stand out,
• induced fission, irradiating the bomb with neutrons and examining what is emitted, and
• muon radiography, now considered speculative, monitoring the path of cosmic rays through the vehicle to detect dense atoms, even in the presence of lead shielding. [See Los Alamos thinking on this possibility.]

The first method is simplest, but is probably not adequate, especially for the more likely uranium bombs. This is because the half-life of U-235 is 704 million years, so there isn’t much radioactivity to detect. Plutonium has a much shorter half-life, and would be easier to detect.

Radiological Dispersion Devices (RDD), or “Dirty Bombs”

Dirty bombs could be built easily by anyone with access to radioactive materials. Radionuclides from industry or medicine, such as radioactive cesium, cobalt, or strontium, could be dispersed by a conventional explosive.

What kind of government reaction is appropriate? How will the public respond to actions by the government? From Making the Nation Safer:

[T]he likely aim of an RDD attack would be to spread fear and panic and cause disruption. Recovery would therefore depend on how such an attack is handled by first responders, political leaders, the media, and general members of the public.

In general, public fear of radiation and radioactive materials appears to be disproportionate to the actual hazards. Although hazardous at high doses, ionizing radiation is a weak carcinogen, and its effects on biological systems are better known than those of most, if not all, toxic chemicals. Federal standards that limit human exposure to environmental ionizing radiation, which are based on the linear, nonthreshold dose-response relationship, are conservative and protective, and the government continues to fund R&D to improve scientific understanding of radiation effects on biological materials.


Attacks on Nuclear Power Plants

Nuclear power plants were designed to withstand the impact of a small plane [I’m sure that design requirements will change for new plants]. Even so, it is a difficult target for a 9/11-type attack because of the low height and small target. Alternatively, armed intruders could attempt to disable the normal and emergency cooling systems (presumably, the plant can be shut down at first sign of attack with no option for restarting), but the chance of success is poor.

Another target is the spent fuel in the cooling pool, but it is thought to be easy to restore cooling, and difficult to create an explosion that would cause a wide dispersal of the uranium pellets. If the fuel is densely packed, the fuel could melt and release Cs-137. The policy suggestion is to transfer 5-year old waste to dry storage. According to Making the Nation Safer,

these are very robust and would probably stand up to aircraft attacks as well.

Of course, nuclear power plants are not unique as targets. Again, from Making the Nation Safer,

The potential vulnerabilities of [nuclear power plants] to terrorist attack seem to have captured the imagination of the public and the media, perhaps because of a perception that a successful attack could harm large populations and have severe economic and environmental consequences. There are, however, many other types of large industrial facilities that are potentially vulnerable to attack, for example, petroleum refineries, chemical plants, and oil and liquefied natural gas supertankers. Their facilities do not have the robust construction and security features characteristic of [nuclear power plants], and many are located near highly populated urban areas. The committee has not performed a detailed examination of the vulnerabilities of these other types of industrial facilities and does not know how they compare to the vulnerabilities of [nuclear power plants]. It is not clear whether the vulnerabilities of [nuclear power plants] constitute a higher risk to society than the vulnerabilities of other industrial facilities.

Indeed, the attention paid to nuclear power plants may make other industrial targets and football stadia more attractive targets.

Also in this series
Part 1 Nuclear Bombs, Nuclear Energy, and Terrorism
Part 2 Today’s Bombs, Making a Bomb
Part 3 Making Bombs from Nuclear Waste
Part 5 Nuclear Proliferation—International Treaties
Part 6 The Bomb Spreads
Part 7 Nuclear Power and the Weapons Threat
Part 8 Wrapup on Nuclear Power Series

Visalia MM Looks at Climate Change

Thursday, October 26th, 2006

Visalia, CA, near Sequoia National Park, is the urban center (pop. 100,000) of Tulare County, a rural, agricultural region with a population of nearly 400,000 people. Transportation is a major issue in this region. People typically drive long distances on a daily basis at high speeds on 2-lane farm roads. The Visalia Friends Meeting (Quaker) is on property donated by the generous (and very friendly) Lovetts, Bill and Beth. Adjacent to the Lovett farm is an experimental community with a decidedly “green” attitude. One home is made with thick straw bales, another with adobe, and another with rammed Earth walls which make air conditioning unnecessary – or less necessary – in the hot summers. (Since nights are relatively cool in the dry Central Valley, windows and attic vents opened in the evening help overcome daytime summer temperatures that frequently rise into triple digits.

The retreat met from Saturday morning through Sunday noon. We started with a PowerPoint presentation and discussion covering the basic facts of Global Warming. In the afternoon we divided into small groups and looked at the questions “What is Mine to Do?” as related to educating oneself and others, changing our personal behavior, and laboring with politicians and environmental groups, to move climate change higher on their lists. (Even environmental groups often ignore Global Warming in favor of issues more popular with their donor base.)

The retreat was long enough that attitudes had a chance to shift. One person made statements early on suggesting that the real work had to be in the policy arena and anything we as individuals could do, which might help us feel good, wouldn’t accomplish much. By the end of the retreat, he was recalling how the personal practice of early Friends refusing to doff their hats to royalty actually helped lay the foundation for more egalitarian attitudes in society. In the end there was a general feeling that witnessing to deeply held beliefs on the individual level can have significant effects on the society as a whole.

Others tapped into emotional obstacles to shifting behavior. Does living a consciously different lifestyle make one feel like a freak? Does it give us a sense of joy in the midst of crisis? Exploring feelings like these is a necessary part of changing consciousness. Almost no one, in this rural area, talked about giving up the car, but people did consider the witness, and concrete conservation implications of driving the speed limit, or even slower, and bicycling short distances. Many saw that exploring their feelings towards change, and teaching others what they learned, is an important part of the solution.

The members of the Visalia Friends Meeting sensed that it was important to make a once-per-month commitment to meet and discuss aspects of climate change. Several short books were mentioned as possible discussion starters, such as Elizabeth Kolbert’s Field Notes from a Catastrophe and Brower and Leon’s The Consumer’s Guide to Effective Environmental Choices: Practical Advice from the Union of Concerned Scientists. (There was a request for a useful guide to making choices after someone in the group complained about the set of suggestions being distributed that included everything including the kitchen sink, with no sense as to which changes are most important. There are many such lists available, not all useful.)

There was also interest in looking at their own behavior, and at least one small group talked of committing to a 10% personal reduction. The starting point for this kind of commitment is a questionnaire to assess greenhouse gas emission implications of current travel and household practices. This questionnaire was circulated beforehand, but few responded before the retreat. With the heightened consciousness of the retreat there was renewed interest in this exercise.

For me, the discussions were rewarding. Most participants searched for changes they could make personally and actions they could take that might make a real impact, rather than focusing on pie-in-the-sky technological fixes. Two teenagers met with me to give feedback on how young people might respond the PowerPoint presentation and what changes would make it more accessible to young people (Many thanks!).

During the weekend I visited old friends and made new ones. This retreat brought together a committed group of people around a topic they had previously considered interesting, if somewhat distant, and resulted in an elevated sense of urgency for this issue. The results were far different from what would have been possible after a one or two hour talk. In the retreat setting they had the time, and took the time, to make climate change part of their own work. I hope that Friends in Visalia Monthly Meeting keep us informed about what they are working on, their successes and difficulties.

Making Bombs from Nuclear Waste

Wednesday, October 25th, 2006

Uranium

Bombs use weapons grade uranium enriched to 90% or more U-235. Lower enrichments are possible, but the bomb is technically more difficult.

Terrorists or nations could obtain uranium bombs by steal one. Alternatively, they can stealing enriched uranium, or enrich uranium to weapons grade from natural or lightly enriched uranium, and make their own bomb. Enriching uranium to weapons grade is complicated enough that it requires government leadership or sanction, so Iran could do it, Al Qaeda can’t.

It is much easier to dispose of weapons grade uranium than plutonium (Pu will be addressed in future post). It only requires diluting the weapons material with natural or depleted uranium (the U-238 left over from the enrichment process), the Megatons to Megawatts program.

Uranium bombs are not made from commercial reactor waste.

Plutonium

Plutonium-239 is the isotope used for weapons. Pu-240, with a half-life of 6,564 years, is a contaminant. It usually decays by alpha decay (emitting two neutrons and two protons), but can also spontaneously fission (break into two much smaller nuclei, emitting neutrons at the same time). These neutrons can start a chain reaction (predetonate) before the plutonium is fully compressed. Predetonation causes a fizzle, a smaller explosion than the bomb was designed for.

Pu-239 is made when U-238 captures a neutron to become U-239. This decays without any neutron release to become Pu-239. If the fuel is left in the reactor, some of the Pu-239 captures a neutron to become Pu-240. Taking the fuel out before long exposure minimizes the amount of Pu-240 formed.

Supergrade plutonium is 98% Pu-239, or more; the rest is Pu-240. Regular weapons grade is 94% Pu-239, 6% Pu-240, and 0.4% other. Reactor grade plutonium is 60%Pu-239, 24% Pu-240, 9% Pu-241, 5% Pu-242, and 1% Pu-238. Weapons grade produces a little over 3 times as many neutrons by spontaneous fission as does supergrade; reactor grade emits 18 times as many. While no military uses reactor grade plutonium, sophisticated bomb designers could make some sort of weapon.

Predetonation is guaranteed in a weapons using reactor grade plutonium; there is a 70% chance that the yield will be less than 10% of what the bomb was designed for. Even weapons grade plutonium has only a 50% chance of a yield more than 40% of design. Supergrade plutonium with only 1% Pu-240 has an 80% chance of exploding at full design yield.

An authoritative National Academy of Sciences report says,

[E]ven with relatively simple designs such as that used in the Nagasaki weapon—which are within the capabilities of many nations and possibly some subnational groups—nuclear explosives could be constructed that would be assured of having yields of at least 1 or 2 kilotons. Using more sophisticated designs, reactor-grade plutonium could be used for weapons having considerably higher minimum yields.

Bodansky says that it is clear that

reactor grade plutonium can be used to make an explosive device that would release a substantial amount of energy. This would be enough to create an explosion that would do great damage due to the blast itself, the heat and radiation produced in the chain reaction, and the radionuclides dispersed in its aftermath.

A national government is more likely to make a reactor particularly to irradiate the uranium for a shorter time. This is simpler, and the bomb is more likely to meet the needs of a government. A terrorist organization might take whatever is available, and worry less about uncertainties in yield.

Once reactor grade plutonium is obtained, there are several obstacles to making a bomb:

• The reactor fuel must be reprocessed to separate out the plutonium.
• The plutonium must be carefully machined, shaped, and assembled. A mistake could kill the workmen.
• The explosives must be arranged for a rapid, symmetric explosion and warm reactor grade plutonium must not overheat the explosives.

One argument against reprocessing reactor fuel is that reprocessing removes the self-protecting element of reactor fuel: fission products which are so radioactive that no one can steal it. Remote handling equipment and reprocessing could work for a national government; again, creating weapons grade plutonium would be simpler.

Some oppose reprocessing of commercial reactor fuel both because nations could make a bomb somewhat faster from reprocessed reactor fuel then from scratch and because theft is now possible. These considerations, along with the relatively high price of reprocessing, led President Carter in 1977 to forego reprocessing. This was not out of fear that the US could develop the bomb, but to discourage reprocessing elsewhere. The good example has not been completely successful. When Carter acted, France, India, Japan, and the UK reprocessed nuclear fuel. Each of these countries has expanded its reprocessing capability since then, and Russia and China have begun reprocessing.

It appears improbable that processing will be abandoned in these countries… [I]t is uncertain for how long Japan will be content to be protected by a U.S. nuclear umbrella…Although a plutonium stockpile would speed the pace of a program to develop weapons, even with no prior stockpile Japan has the personnel and facilities to develop nuclear weapons quite quickly, should it choose to do so.

While it is unlikely that the famed high school student could make a plutonium weapon, a well-organized terrorist group could acquire expertise and equipment.

It might be argued that even for such a group, it would be irrational to proceed with a plutonium bomb when there are simpler alternatives for major destruction and terror. However, it is not prudent to rely on the rationality of terrorist groups.

So good security is a must.

Also in this series
Part 1 Nuclear Bombs, Nuclear Energy, and Terrorism
Part 2 Today’s Bombs, Making a Bomb
Part 4 Terrorist Targets
Part 5 Nuclear Proliferation—International Treaties
Part 6 The Bomb Spreads
Part 7 Nuclear Power and the Weapons Threat
Part 8 Wrapup on Nuclear Power Series

Today’s Bombs, Making a Bomb

Tuesday, October 24th, 2006

Detour

Bombs are bigger today.

One kiloton was originally defined as the explosive equivalent of 1000 tons of TNT. This definition was found to be imprecise and so the term was redefined to be the release of 10^12 calories of explosive energy. The largest weapon ever tested was a 50 megaton (Mt) (1 megaton = 1000 kilotons) weapon that the Soviets exploded 3.5 kilometers above Novaya Zemlya on October 30, 1961. For comparison, the total tonnage of bombs dropped during World War II was approximately two Mt, and during the Vietnam War it was approximately 6.3 Mt.

Both the US and Russia have bombs in the Mt range, Pakistan and India have bombs in the 15 – 20 kT range.

Although nuclear weapons are radioactive and this will eventually cause cancers later, the important issue is the size of the bombs that one plane can carry. For example, the bombing of Dresden involved les than 3 kt of bombs, and many, many planes.

Nuclear Winter

A few decades back, nuclear winter was considered to be a possible result of a superpower nuclear war. So much dust is kicked into the air, it’s like being hit by a major meteorite (such as occurred 65 million years ago, killing the dinosaurs and a whole bunch of other species). The original assumption was thousands of Mt in nuclear weapons leading to a dramatic decrease in the Earth’s temperature. However, the people involved in the original calculations were not bomb experts, they also assumed a flat Earth, and generally, it is now believed that a nuclear war of this magnitude would produce some cooling of the Earth during the day due to all the dust, a warming during the night because the heat can’t escape, for a short period of time. It is no longer thought to be a major consequence of an all out nuclear war.

Terrorists and the bomb

Back to Bodansky:

Currently nuclear war between the major nuclear powers (the US and Russia) and the intermittently threats of an India-Pakistan both appear remote.

The most imminent threat for the United States, and perhaps for the world as a whole, appears to be from the possible use of single weapons by terrorist groups.

A 1-kt bomb could kill half of people from thermal burns within 610 meters (0.4 miles). Additionally, people as far away as 790 meters (0.5 miles) could receive an absorbed dose of 4 grays (Gy). Of 23 Chernobyl victims receiving doses between 4 and 6 Gy, 7 died. A ground level explosion could create heavy local fallout: up to 4 Gy for a distance of 5.5 km (3.4 miles) downwind.

Because much of the dose is due to very short-lived radionuclides, the rate falls very rapidly with time–by approximately a factor 10 when the time increases by a factor of 7. Thus, at 7 h, the dose rate is 10% of the 1-h level, at 49 h, it is 1% of the 1-h level.

Preferences on bomb designs are shifting.

It is considerably easier to make a bomb using enriched uranium than to make one using with plutonium, and uranium may be becoming the material of choice for countries or groups that want to build a bomb with minimal effort and chance of detection.

This is because the spontaneous fission rates for Pu is larger, so a more complicated means is needed to combine the subcritical masses to make a supercritical mass. More on this in the next post.

Also in this series
Part 1 Nuclear Bombs, Nuclear Energy, and Terrorism
Part 3 Making Bombs from Nuclear Waste
Part 4 Terrorist Targets
Part 5 Nuclear Proliferation—International Treaties
Part 6 The Bomb Spreads
Part 7 Nuclear Power and the Weapons Threat
Part 8 Wrapup on Nuclear Power Series

Searching for Information on Climate Change?

Tuesday, October 24th, 2006

RealClimate, a site run by climatologists, has expanded its search function to include IPCC, goverment labs, research institutes etc.

RealClimate provides (sometimes technical) analyses of climate change topics, and often has a good discussion, including questions and answers, in the comments.

Nuclear Bombs, Nuclear Energy, and Terrorism

Monday, October 23rd, 2006

Many observes believe that the most profound problem with using nuclear energy for electricity generation is the connection between nuclear power and nuclear weapons. In this view, the threat of nuclear weapons proliferation increases if the world relies on nuclear power, because nuclear power capabilities could be translated into nuclear weapons capabilities. The relative merits of renewable energy and nuclear fission energy (omitting fusion as still speculative) as eventual substitutes for fossil fuels are highly controversial, with unresolved arguments over relative economic costs, environmental impacts, practicality, and safety. However, the weapons connection is unique to nuclear fission energy and constitutes, for some people, a reason to limit or abandon it.

Giving up nuclear power would obviously avert the danger that nuclear power facilities might be diverted to weapons purposes. However, it would not avert all dangers of weapons development. It is quite possible to have nuclear weapons without nuclear power as well as nuclear power without nuclear weapons. In fact, most countries that have nuclear weapons had those weapons well before they had civilian nuclear power. Other countries that have made substantial use of nuclear power, such as Sweden and Canada, are rarely perceived to be potential nuclear weapons threats.

Nonetheless, a program in one area can aid a program in the other.

From David Bodansky’s Nuclear Energy (second edition), the beginning of two chapters examining these links. I will be summarizing these chapters over a number of posts, and providing some background. Obviously, you would get more detail reading the book!

Both nuclear power and nuclear weapons use U-235. Power reactors use lightly enriched uranium (LEU), natural uranium (0.7% U-235) enriched to 2 – 5% levels. Weapons grade has been enriched to 90%+ U-235. U-235 is the active ingredient in both not because it is more radioactive than the much more common isotope, U-238, but because U-235 plus a neutron does interesting stuff: it becomes U-236 which fissions, releasing lots of heat (the reason nuclear or fossil fuel or geothermal power is used) and lots of neutrons to continue the process. U-238 plus a neutron becomes U-239, which decays into Pu-239; this gives off very little heat and releases no neutrons.

Atomic bombs (using U-235 or Pu-239) depend on an explosion pushing together two sub-critical masses (not sufficient to provide chain reaction) to make a super-critical mass. With a super-critical mass, enough neutrons are generated fast enough to irradiate all of the U-235 atoms in a small fraction of a section.

The Hiroshima bomb used U-235. It killed perhaps 100,000 people immediately or within a few weeks, and had an energy yield equivalent to 15 thousand tons (kt) of TNT. The 21 kt Nagasaki bomb, using Pu-239, killed somewhat fewer people. Additionally, from 1950 – 1990, there have been 421 excess cancer deaths(above that expected). No genetic effects have been observed. [I heard several years ago that with improvements in bio-assays, a study was intended for Nagasaki victims to find otherwise undetectable genetic effects. I also heard that residents of Nagasaki were not lining up to participate. I don’t know whether the study was done and whether the results were positive or negative.]

Atom bomb victims receive treatment under a Red Cross flag on the outskirts of Nagasaki following the attack.

Atom bomb victims receive treatment under a Red Cross flag on the outskirts of Nagasaki following the attack.

Also in this series
Part 2 Today’s Bombs, Making a Bomb
Part 3 Making Bombs from Nuclear Waste
Part 4 Terrorist Targets
Part 5 Nuclear Proliferation—International Treaties
Part 6 The Bomb Spreads
Part 7 Nuclear Power and the Weapons Threat
Part 8 Wrapup on Nuclear Power Series

WeSupportLee Looks at Proliferation Issues

Monday, October 23rd, 2006

I asked a pro-nuclear blogger, WeSupportLee, to address nuclear proliferation issues.

She looks at a program that converts Russian military weapons material to commercial power reactor fuels (Americans think that it’s just cheaper to throw away the weapons materials, but another solution needed to be found for what Russians consider a resource). Also discussed are shifting research reactor fuel away from highly enriched uranium and proliferation-resistant fuel for nuclear power.

However, TVA commercial power reactors are involved in maintenance of US nuclear weapons—creating tritium (hydrogen with 2 neutrons) to replace the tritium that decays at a rate of 5.5%/year. This blurs the line between nuclear power and nuclear weapons, and many pro-nuclear power, anti-nuclear weapons people want TVA to discontinue this project.

Check out WeSupportLee for her take on other topics, mostly climate change, North Carolina events, and the Prius. I appreciate her work: reliable, methodical, and no wasted time defending dumb comments: “Climate change isn’t happening and nuclear power is the best way to address climate change.”

I will begin addressing proliferation issues by summarizing two chapters in David Bodansky’s Nuclear Energy (second edition) over several posts. Bodansky (professor at University of Washington) has written an excellent and readable book on nuclear power. I also want to describe my trip to the Friends Meeting in Visalia, CA, to participate in their climate change retreat. Good work Visalia!

Let me know if you have particular proliferation issues you would like to see addressed. I am not an expert, but will try to find answers.

Pollinators’ Decline Called Threat to Crops

Thursday, October 19th, 2006

Today’s Washington Post has an article on pollinators, in rapid decline in many areas of the world.

Birds, bees, bats and other species that pollinate North American plant life are losing population, according to a study released yesterday by the National Research Council. This “demonstrably downward” trend could damage dozens of commercially important crops, scientists warned, since three-quarters of all flowering plants depend on pollinators for fertilization.

Important to both farmers and ecosystems:

“Canadian black bears need blueberries, and the blueberries need bees” for pollination, [Peter] Kevan [professor at the University of Guelph, Ontario] said. “Without the bees you don’t have blueberries, and without the blueberries you don’t have black bears.”

The article suggested some reasons for the plummeting levels of pollinators:

A number of factors have cut pollinators’ numbers in recent decades, the researchers said. Introduced parasites such as the varroa mite have hurt the honeybee population, and pesticides have also taken a toll. Bats, which carry pollen to a variety of crops, have declined as vandalism and development have destroyed some of their key cave roosts.

There are other problems I’ve seen in various articles: one prediction of global warming models is that the climate will change to fewer seasons/days we call normal (normal is changing) and more we call extreme. Many insects cannot adapt to the increase in extremes now occurring, whether from global warming or other causes.

The NRC report looks at aspects of climate change impacts:

Declines in many pollinator groups are associated with habitat loss, fragmentation, and deterioration … Changes in phenological synchrony and in distributions of pollinators and plants result from global climate change could lead to a decline in interactions between flowers and pollinators. Disruption of migratory routes is evident in hummingbirds, nectar-feeding bats, and some butterflies.

The report also looks at the effect on honeybees from pesticides used on crops and from mosquito control. Other causes include monoculture and other agricultural methods such as “loss of field margins” and replacing crop rotations involving legumes with fertilizer.

The deterioration in the ozone layer is a humongous problem — after all, life could not come onto land until there was sufficient stratospheric ozone to protect plants and animals from UV. But the solutions are relatively simple. The problems leading to pollinator decline are harder to find solutions to. See the NRC report for some suggestions.

8 Week Carbon Diet

Thursday, October 19th, 2006

Visiting Doonesbury, I saw the Slate Green Challenge: beginning October 23, we are invited to reduce our carbon emissions 20% over an 8 week period, from our current level. This includes the Thanksgiving holiday, so some of us will need to use mass transit to get to our holiday feast.

The numbers Slate uses are not correct, but the concept is — let us know if you take the Challenge, your successes and difficulties, and whether the feelings tend to joy or resentment. If you don’t want to take the Challenge, why? Share what you learn about yourself and the process with the rest of us.

We have as much to learn from your feelings as your tips on how to reduce emissions fast.

My answer: my big reductions in greenhouse gas emissions need to be made during summer travel, so the timing is wrong.

A large set of interesting comments on Reducing Our Own Emissions 10%, including Wendy’s on the big changes in attitudes and behaviors in her Quaker Meeting.

Changing Our Behavior

Monday, October 9th, 2006

There was a good discussion on the post Reducing Our Own Emissions 10%.

Before I get to what these and other Friends (and some non-Friends) are saying about changing our greenhouse gas behavior, the origin of the discussion:

I wrote If We Could Move Like Centipedes in part to address people’s sense that “there is nothing I can do” because “I am just one person”. If enough of us could move, we could get out of danger, and this post suggests several ways for us to act. One of these is to reduce our own emissions 10% in the coming year. I took these ideas to Friends General Conference, to both a workshop and an interest group, and the ideas made it into an epistle for Friends everywhere. Then two California Friends Meetings in Pacific Yearly Meeting began considering committing to 10% reductions in GHG emissions in the coming year for all Friends in the Monthly Meeting.

There are several other actions that count as motion: educating ourselves about the science, impacts, policies, and the emotional and spiritual aspects of what will happen — from negative emotions like guilt to positive ones like responsibility for the solutions — and behavior change. Educating ourselves about how to communicate on climate change. Laboring with legislators, and if that is unsuccessful, replacing them.

It would not have occurred to me to ask all Friends to change our GHG behavior. Now that the question is being asked, I am interested in the discussion. It is useful to ask hard questions of one’s self, even if today’s answer is “not now”, because it is important that we try to walk in God’s path consciously.

Positives (from the comments, and what I’ve been hearing – what have you been hearing? Let us know):

• Don exudes pride and enthusiasm. (He deserves to feel this way!) This is typical: changing our lives, so we are happier with who we are, feels really, really good. I don’t know how much time Don put into these changes, but most of us spend much longer thinking we should do something than the something actually takes. There are several suggestions in these comments on how to reduce greenhouse gas emissions. Bob and another Don point out there are numerous easy changes in the house.

• Those who have already changed the most are better able to see how to make more changes. It often doesn’t feel like an obligation, more like walking further on the path. Many still use the word joy months or years later.

Others I know are taking the bus locally even when they own a car, or taking trains short distances (24 hours), particularly to Friends events.

• Liz, Pam, and Gretchen discuss psychological and family conflicts: travel feels different when it’s to visit sick family members (and so rules about whether the airplane is OK are different). The family/housemate likes warmer winter temperatures, cooler summer temperatures, short flights over long bus trips, and no clothes line. (Gretchen’s comments include many more details.) It’s much harder when the desire to fly long distances for vacations is more vital than, or at least strongly competing with, the desire to reduce GHG emissions. Chris also talks about the difficulties – he’s created a life where he accepts jobs and committee meetings far from mass transit and then needs a car.

Chris also discusses the benefits of community efforts, like the “One Less Car Day!” October 4. It must be a trend, because I bicycled by an elementary school 20 miles east of SF, where a big sign announced October 2 – 6 is “Walk to School Week”. (As teachers know, students who get to school by a combination of muscle power and bus arrive more settled and ready to study.)

• Anonymous says record-keeping, ugh. He (or she) also faces the family member/tenant/housemate challenge, but sees working with housemates as a behavior to change – from not at all to more often. Instead of cutting back 10%, he suggests a 20% reduction from however much you consider necessary (what is necessary for a typical American or Canadian? others?). He walks and bicycles more than he flies and drives (I’m assuming that the actual numbers given were typos, walking 1/10 as many hours as one flies is a lot of flying!)

• Several people point out that much can be accomplished by higher efficiency in distribution power, switching away from coal, etc, We need to work with our legislators to mandate improvements. And taxing GHG emissions (through a cap and trade program), and taxing ourselves to pay for third world improvements.

OK –here’s the question – are people actually working with their legislators, other than signing those petitions no one reads? Personal visits to legislators from a group are more likely to be effective, particularly if you are prepared. If not, we shouldn’t list this under behavior change.

Gretchen’s new bike is inspiring her to help with local bike transportation issues.

• Others like the idea of planting trees or buying carbon offsets. This can help, as can working for nuclear power instead of coal (or solar or wind power, but at this point, they are not ready to displace an entire large coal power plant.) (For the question on replacing your car with a more fuel-efficient model, see post on how airplanes and cars compare. But don’t trash your inefficient car, as it may be an improvement for someone else – one person told me that he makes sure each car he buys gets at least 5 mpg better than the previous one.)

Negatives:

• We find it easier to talk about changing light bulbs than changing behavior, beyond turning off lights in empty rooms.

Transportation is particularly difficult: many see no alternative to current choices. Alternatives do exist, but we have trouble seeing them. Sort of like the days of slavery, when so many could not imagine cooking their own meal or planting their own crops. Life can change – but we can’t see it, even if it leads to a way of living that makes us happier with who we are.

It is hard, but relatively easier, to personally buy more efficient bulbs, shift electricity away from high GHG emitting sources, mandate better buildings and more efficient appliances and cars, and decrease industrial GHG emissions. Low GHG substitutes for fuels will be harder to come by (some can be replaced by cellulosic biofuels, but we will also be burning lots of coal to liquids, or synfuel, soon). Most of us find the roundtrip flight once or several times/year, or long car trips at high speeds, hard to reflect on. Most of us find it hard to shift toward a world (in the US anyway, worldwide some are already there) where people live and work near good mass transit, and use it, or to restrict ourselves to activities accessible by muscle or mass transit. Where we schedule longer vacation and work trips to accommodate the extra time required for bus and train. Where we make longer trips, because we will schedule many fewer of them.

• While some cities/towns both have good transit and are affordable, this is often not the case in the US. It is important that our cities be places where the poor (and middle class) are welcome, and where they can get around.

• Some appear to be relying strongly on the effectiveness of offset programs. Some say they’ve cut back as much as possible, but still must make that trip once/year, but others talk about buying GHG offsets in the same way people in the Middle Ages purchased indulgences, possibly to equal effect.

• This discussion on behavior change is not occurring in most Friends Meetings yet (I hope this statement is not correct, that in a future post I will be able to say that lots of Friends have taken the call from the Friends General Conference epistle to heart).

Comparing Driving and Flying

Sunday, October 8th, 2006

Updated — it turns out EPA provides GHG emissions for cars!
Second update — two examples added at end.

In the previous post, the greenhouse gas cost per airplane mile is calculated at 2 – 4 times the cost of the fuel alone, anywhere from 1 – 1.9 pounds carbon dioxide equivalent per mile, a little more for people who don’t walk to the airport. How do cars compare?

Go to EPA to find GHG emissions for cars – you may want to divide their fuel economy and multiply by your own FE (typically 20 – 30% lower than EPA indicates). You can add the cost of manufacturing the car, see examples below*.

In the particular examples chosen, the Toyota Prius (assume 45 mpg) pollutes 0.62 pound carbon dioxide equivalent/mile, and the Dodge Durango (12 mpg) 2.1 pounds.

It appears that the airplane is worse than the Prius and a better choice than the Durango, at least for one person. Although the fuel economy of airplanes is actually about the same as a Prius, airplanes deposit water vapor, etc high in the atmosphere, so create about 2 – 4 times as much damage as would be expected from the amount of oil used.

However, the typical person makes choices based on time rather than distance: both commutes and vacations are determined by travel time. Many opt for some combination of more trips and longer trips. (Ditto for convenience cooking equipment – fancier meals, not reduced cooking time. Computers for easier word processing – nicer layouts, not faster turnaround.)

What figures into your decision on whether to fly or take slower transportation? Is the environment a part of your calculation?

*Separate GHG costs into two portions, the cost of manufacturing the car and the cost of using the fuel.

First, the car. The US Department of Transportation says that the average car lasts 125,000 miles.

Find the weight of your car. On the Road in 2020 (pdf) provides GHG costs of material: assuming that your car is made from mostly recycled materials and will be recycled in turn, multiply the weight in pounds or tons by 2.5 to get the amount of carbon dioxide released in manufacture in pounds or tons (note: if your car is extra light because it’s heavy on the aluminum, the GHG emissions for manufacture are higher per pound, sigh).

A Prius weighs 2,890 pounds, a Durango 6,600 pounds. Multiply by 2.5 –the Prius manufacture GHG cost is 7,200 pounds carbon dioxide equivalent, the Durango is 17,000 pounds. Assuming that the car lasts 125,000 miles, this comes to 0.058 pounds/mile for the Prius, 0.14 pound/mile for the Durango.

EPA says the Durango gets 15 mpg, emitting 12.0 tons GHG in 15,000 miles, so most drivers get 12 mpg or worse. EPA says the Prius gets 55 mpg, emitting 3.4 tons in 15,000 miles, so most drivers get 44 mpg or worse (actually, Prius drivers tend to drive more efficiently, so perhaps the Durango real driver penalty should be higher).

Divide by 0.8 to get more realistic driver emissions, and then divide by 15,000 miles and multiply by 2,000 pounds to get the per mile emissions: 2 pounds carbon dioxide equivalent/mile for the Durango, and the Prius 0.57 pounds. The greenhouse gas cost of manufacturing the Prius adds another 10% to the fuel cost (just over 0.05 pounds), 7% more for the Durango.

You can add your two figures to get total greenhouse gas/mile. For the Prius, this will be 0.62 pounds/mile. The Durango comes in at 2.1 pounds/mile.

If you don’t want to do weight separately, add 10% to your fuel GHG emissions for a high fuel economy car, and 7% for one with low fuel economy.

If you want to pay GHG tax on your car, say $20 – $50/ton (see previous post), multiply pounds carbon dioxide equivalent/mile by the number of miles/year, and divide by 2,000 pounds in a ton to get GHG emissions in tons. Then multiply by the tax/ton. Note: this ignores GHG from other pollutants, which are relatively small unless you always drive your car short trips – your car is much more polluting cold than warm. If most of your trips are less than 5 miles, round up in calculating GHG costs.

Example 1:
Prius. You get about 44 mpg, and your total emissions, car plus fuel, are about 0.62 pounds/mile. You choose to charge yourself a $35/ton tax. You drive 8,000 miles/year.

GHG emissions = 12,000 miles * 0.62 pounds CO2e/mile = 7,500 pounds carbon dioxide equivalent

Tax = $35/ton * 1 ton/2,000 pounds * 7,500 pounds = $130. This doesn’t add much to your yearly costs. At $3/gallon, you’re paying $800 for gasoline. Donate the money to improving your insulation, or someone else’s, and ask your legislator to add this tax to everyone.

More expensive example:
Durango. You get 12 miles/gallon, and your total emissions, car plus fuel, are 2.1 pounds carbon dioxide equivalent/mile. You drive 12,000 miles/year, and charge yourself $50/ton.

GHG emissions = 12,000 miles * 2.1 pounds CO2e/mile = 25,000 pounds carbon dioxide equivalent

Tax = $50/ton * 1 ton/2,000 pounds * 25,000 pounds = $630. This adds more to your yearly costs, but at $3/gallon, you’re paying $3,000 for the gasoline. Donate the money to funding a new car, and ask your legislator to add this tax to everyone.

What Should We Add to the Airplane Ticket Price?

Monday, October 2nd, 2006

How much should we be paying for airplane flights? It’s a frequently asked question, at least I’ve been asked often.

Surprisingly, people who fly pay no sales tax on flights that leave the state, nor do they pay the fuel taxes required of car and truck drivers. Flight taxes (partially?) cover security costs and air traffic control, rather than contributing to the common good. This means that those who don’t fly subsidize those who fly often.

Industry reports that airlines now get 46.8 passenger miles/gallon. The Intergovernmental Panel on Climate Change (IPCC) Special Report Aviation and the Global Atmosphere suggests that the radiative forcing is 2 to 4 times higher than the carbon dioxide emitted predicts, in part because of aerosols, NOx, water vapor, and other gases released in the upper troposphere.

Let’s use an example of a one-way trip from Los Angeles to New York to London, paying American fuel tax on the first leg, British fuel tax on the second, and greenhouse gas taxes of $20 (expected tax in the next decade or two) or $50 (further along) per (American) ton of carbon dioxide.

This analysis will ignore sales tax for tickets. You may wish to pay your share of living in society by paying extra for your ticket: sales tax is 8.25% in Los Angeles, higher in New York City, and much higher in London.

Fuel tax is currently not applied to commercial airlines. Californians pay 18.4 cent/gallon federal plus 45.9 cent/gallon state for fuels. This is intended to cover road construction and some mass transit. On a $2/gallon base price, add 16.5 cent for sales tax. British fuel tax is about $4/gallon.

The leg from Los Angeles to New York is 2,500 miles. Assuming 46.8 passenger miles/gallon, one person’s share is 53 gallons of fuel. CA and federal fuel taxes, if applied, would add $34 to ticket price; sales tax adds $9.

On the New York to London leg (3,500 miles), the British fuel tax on the 74 gallons you are responsible for adds $296 one way, if applied.

Assume an initial greenhouse gas tax of $20 per (American) ton carbon dioxide equivalent*, and just over 0.5 pounds carbon dioxide eq/passenger mile, including upstream costs.** But the actual GHG effect is much greater, as if we added between 1 and 1.9 pounds carbon dioxide/passenger mile to the atmosphere, using the 2 – 4 x factor recommended by IPCC. For the LA – NY leg, this comes to 1.2 – 2.4 tons carbon dioxide equivalent. Add between $25 and $48 GHG tax for a one-way trip between coasts.

The leg between New York and London adds between 1.7 and 3.3 tons carbon dioxide equivalent, using the 2 – 4 x factor, and the $20/ton greenhouse gas tax adds between $35 and $65. Total for both legs: $60 – $110, one way.

This is the price of an early greenhouse gas tax. If the tax increases to $50/ton, the LA-NY leg should include a greenhouse gas tax of somewhere between $62 and $111. The NY-London leg adds between $88 and $166. Remember, these price increases are not for the round trip. Total for both legs, $150 – $280.

A longer answer for all those who have been bugging me about greenhouse gas offsets for flying. Please let me know if this analysis could be improved.

To do this yourself:

Find air miles for one way or round trip at some calculator such as WebFlyer.

Multiply number of miles by $0.01 – $0.019/mile (accounts for IPCC fudge factor on extra greenhouse gas effects of airplanes) for a greenhouse gas tax of $20/ton carbon dioxide equivalent.

Multiply miles by $0.025 – $0.048/mile (accounts for IPCC fudge factor) for a greenhouse gas tax of $50/ton carbon dioxide equivalent.

Divide number of miles by 46.8 to get gallons of fuel per passenger, then calculate fuel and sales taxes for your state.

Add sales tax to ticket cost (optional).

Invest the money in reducing your own emissions, or someone else’s. You can buy compact fluorescent bulbs, for example, and ask the local food bank to distribute them, perhaps 3 per family.

Note: I’ve changed assumptions about greenhouse gas tax since first posting.

*Sometime in the next decade or two, greenhouse cap and trade policies will create an effective greenhouse tax of about $20/ton carbon dioxide. People in policy differ on how fast technological change and policy implementation will reduce emissions, how much can be accomplished by mandate (better fuel economy for cars and air conditioners) rather than capping emissions, etc. Some people in policy believe that cap and trade policies will create a tax of more than $100/ton carbon dioxide, others that it will never go over $50. Failure to address climate change seriously today will lead to much higher costs tomorrow.

** This assumes 21.1 pounds CO2eq/gallon jet fuel, plus 16% for upstream costs of discovery, refining, and transportation. Greenhouse gases for building the airplane are not counted, and are relatively small compared to the GHG cost of the fuel.

Talking with Family

Monday, October 2nd, 2006

Lots of good comments and questions to the previous post on cutting our own greenhouse gas emissions, and I will address a couple of the points raised soon.

Several people have talked to me recently about the frustration of communicating with family members about the importance of climate change. What are your experiences, and do you have recommendations?

in talking with your own children, and with your generation and older…