Archive for September, 2006

Reducing Our Own Emissions 10%

Friday, September 22nd, 2006

Two Quaker Monthly Meetings in California (Pacific Yearly Meeting) will be looking at a proposal to commit to reducing our own greenhouse gas emissions by 10% in the coming year. What will it take?

For people who fly, one tenth of the miles (or more) shifted to mass transit. For people who drive, some combination of driving less, driving more efficiently (a car with higher fuel economy, no more than 55 mph, etc), driving with others rather than alone. In the house, most people can cut back 10% easily by switching to more efficient light bulbs, replacing old appliances if not efficient with new ones, turning off the computer if you won’t be using it for a while, heating and lighting only rooms you are in. During the California electric crisis, we cut back 10% on electric use – when interviewed for local TV, everyone said, “I didn’t do anything really, just…”

Caveat: there will be a major improvement in energy efficiency soon, due to California’s new regulations. For example, vampire power — the energy sucked up by electronics and appliances not being used — will be more carefully regulated in coming years. For many microwave ovens, more electricity is consumed by the clock and keypad than by the oven!

For the first year of changing our behavior, it may make sense to ignore greenhouse gas emissions from mass transit, and concentrate on reducing use of the car, airplane, and motorized boats.

Comments? Is this a good goal for the first year, impossible goal?

Nuclear Reactor Safety

Tuesday, September 19th, 2006

An important theme in Jared Diamond’s Collapse is how often people won’t change behavior that gives status; the Easter Island example is cutting down trees for statues. There are many examples today, such as how and how often we drive and fly.

Another way we can get into trouble is by not changing our views with changing realities. Union of Concerned Scientists has just produced a report on the dangers of nuclear power. The report is new, but the data are mostly old, except for the Davis-Besse plant.

From David Bodansky’s Nuclear Energy (Second Edition), chapter 14:

The historical record of nuclear reactor performance can be interpreted as showing that they are very safe or that they are very dangerous. The former conclusion follows if one limits consideration to plants outside the former Soviet Union (FSU). The latter conclusion follows if one focuses on the Chernobyl accident and takes it as a broadly applicable indicator.

As of 2003, commercial reactors outside the FSU have a cumulative operating experience of more than 10,000 reactor years (by now it’s 11,000 reactor years). No one has died from an accident from radiation exposure, neither worker nor public. [Two people died in a Japanese reprocessing accident.] Military reactors in the West have had problems: in 1961, three army technicians died.

No reactor has a zero chance of accident. Accidents range from release of radionuclides (Chernobyl) to incredibly expensive damage to the reactor core (Three Mile Island, TMI) to near misses to harmless breakdowns. The latter two categories can be expensive if remedial measures and lost time add up.

Potential major accidents are of two types:

Criticality accidents, where the chain reaction becomes uncontrolled. In light water reactors, negative feedbacks (feedbacks which work in opposition to whatever is happening) make this event improbable.

Loss-of-coolant accidents, where the reactor becomes so hot that melting of the fuel cladding and the fuel can occur. Radioactive materials could possibly escape from the reactor vessel and perhaps the outer reactor containment. The TMI accident resulted in substantial core melt, but no large loss of radioactivity from containment.

Criticality accidents are essentially impossible in Western reactors, but loss of coolant remains a concern.

Achieving Reactor Safety—Changes in Design

• Emphasize passive safety systems even more. Active systems depend on proper responses from pumps or valves, for example, while a passive system might depend on gravity or that warm metal expands.

• Improve redundancy, either more of identical units or more than one way to respond in an emergency.

Multiple barriers or defense-in-depth to prevent radionuclide release: zircaloy cladding of fuel, pressure vessel and closed primary cooling loop, and heavy outer reactor containment. The reactor containment was successful for TMI, but no containment system existed in the Chernobyl reactor.

• [One academic told me that current design assumes a malicious operator, because there is no essential difference between a malicious operator and one who puts paper over warning lights. This is a subset of passive systems changes.]

• Do probabilistic risk assessments on each design. While this does not provide an accurate risk assessment, they suggest areas of relatively high risk.

Post-TMI Safety Developments

The accident at Three Mile Island showed that efforts by government and industry up to 1979 were inadequate. The nuclear reactors themselves, operator training, and inter-utility communication needed improvement.

One consequence of improving reactor design, a very expensive delay post-1979 of new construction and retrofit of old reactors, was a general improvement in capacity (90% today for nuclear power plants, 73% for coal); both accidents and refueling take time. Output dropped between 1979 and 1982, began to rise substantially in the mid-1980s, and reached a high in 2002, six years after the last American nuclear power plant went into operation.

The Institute of Nuclear Power Operations was established to improve communication. The Nuclear Regulatory Commission (NRC) intensified its watchdog role.

Their data show a decrease in unplanned scrams, automatic shutdowns of a reactor following failure. The rates were 7.3 per 7,000 hours of reactor operation in 1980, 1.2 in 1990, and under 0.1 in 2001. One result was the improved capacity factor, referred to earlier.

The rate of industrial accidents (this has nothing to do with radiation) per 200,000 worker-hours in 2001 was 0.24 for nuclear reactors, compared to 4.0 for U.S. manufacturing as a whole. [The accident rate is likely higher/worker-hour for the coal industry. Coal requires many more workers to supply the same amount of energy, a coal train every day versus a truckload of fuel every year or two, as 100,000+ times as much fuel is required. So no matter how coal compares per worker-hour, both worker safety and transportation accidents for coal compare unfavorably per kWh.]

There are still problems, in spite of all these improvements. In early 2002, deep corrosion was discovered during refueling in the Davis-Besse reactor vessel head. Boric acid had leaked through cracks in nozzles, producing a cavity 4 in by 5 in, to a depth of 6 in, large enough that it might have been discovered earlier if workers had been sufficiently vigilant. Inspections at other similar reactors produced no evidence of similar leaks.

How serious was the leak? There was no radioactivity release, and no damage except at the location. The NRC analysis was not complete when the book was published, Perhaps there was no likelihood of core damage, even if the corrosion penetrated the wall. While the safety systems appear to have been intact, and would likely have worked in spite of the corrosion,

the failure to detect and correct the corrosion promptly showed serious weaknesses in the monitoring procedures of the reactor operator and the NRC. This single event does not negate the very good and improving record of nuclear reactor performance, but should serve as a reminder against complacency.

The cost to Davis-Besse was hundreds of millions in repair costs, tens of millions in fines, and two former workers, and one former contractor, indicted for providing false information.

If I get a chance, you’ll see a writeup on safety in the coal industry.

Union of Concerned Scientists is also hosting a cartoon survey, choose your favorite cartoon on the attacks on science.

Waiting for the Monsoon

Saturday, September 16th, 2006

MALBOROU, NIGER–On a hot afternoon in July, a chanting, dancing, drumming crowd has formed on the main road that crosses the village, half an hour’s drive north of the border with Benin. The villagers have begun the rain dance. They want to bring on the monsoon that drenches the earth every year from June to August; it’s now several weeks late. The millet crop needs 3 months to ripen, and time is running out for planting the seed.

The people who live on the flat, reddish-brown, dusty landscape of southern Niger depend heavily on the West African monsoon: In 2001, 39% of the Nigerian gross domestic product came from agriculture, which employs 90% of the workforce and involves virtually no irrigation. Niger’s neighbors throughout the Sahel, the strip of Africa that stretches across the continent directly south of the Sahara, face similar circumstances. From the 1970s to the 1990s, the Sahel suffered severe drought, leading to some of the worst famines in recent history. Precipitation levels began to rise beginning in the late ’90s, but crops were once more devastated by drought in 2005; 2006 did not begin well.

From Science, August 4, pp 608 –9

Lack of good weather data in Africa means scientists can’t help improve model predictions: the current network of 1152 weather watch stations (not all of which report) is 1/8 the minimum number needed. A European-led consortium of 140 institutions from Europe, America, and Africa has begun a 10-year project to monitor and thoroughly describe the West Africa monsoon: rainfall; cloud structure and water content; amount, movement and characteristics of air-borne particles; distribution of water in river systems; etc.

Africa’s weather is affected by what happens on other continents; in return the Sahara and Sahel regions affect the entire planet. The Sahara supplies much of the world’s aerosols (suspension of fine solid or liquid particles). Sahel weather systems during monsoons affect Atlantic hurricanes (I have no clue how).

Meanwhile current models are all over the place as to what will happen in the future in the Sahel: severe drying, wet conditions, modest drying. Models show varying sensitivity to land or sea temperatures, for example, and with so little data, it’s difficult to fit the models to the data to see which work better.

The rains arrived this year at the end of July; later would have been too late. Hopefully within the decade, it will be possible to know whether this is climate change or seasonal variation.

Sea Ice Melts Faster

Thursday, September 14th, 2006

Maximum sea ice in the Arctic is shrinking more rapidly than before. Satellites showed an average shrinkage of 1.5% per decade since 1979, but for this year and last, it is now 6% per year.

There’s still a fair amount of ice left, about double the size of the United States. But this will change; already the melt season is two weeks longer. Oceans absorb more than 95% of light, while ice reflects some 80 – 90%, the water around and under the sea ice warms, and the melt rate speeds up.

This process will not increase sea level (melt ice in a full glass of water and check for spills), but will freshen the water. Concerns about shutting down the currents due to a large increase in fresh water center on the much greater impacts of rapid melting of Greenland’s glaciers. However, marine animals are being badly hit:

According to [Joey] Comiso [a research scientist at NASA’s Goddard Space Flight Center], if the winter ice retreat continues, the effect could be very profound, especially for marine animals. “The seasonal ice regions in the Arctic are among the most biologically productive regions in the world,” he said. “Some of the richest fisheries are found in the region, in part because of sea ice. Sea ice provides melt-water in spring that floats because of low density. This melt-water layer is considered by biologists as the ideal layer for phytoplankton growth because it does not sink, and there is plenty of sunlight reaching it to enable photosynthesis. Plankton are at the bottom of the food web. If their concentration goes down, animals at all tropics level would be deprived of a basic source of food.”

Nuclear power and greenhouse gas emissions

Tuesday, September 12th, 2006

A recent argument against nuclear power which I have now heard too many times is that nuclear power is almost as bad as natural gas because there are such great quantities of greenhouse gas emissions in the enrichment process. The authors of the arguments, Jan Willem Storm van Leeuwen and Philip Smith (the rebuttals standardize the paper as SLS), have not used the normal process used by those who want to be heard by scientists: get your arguments together for peer review journals, and then wait for the judgment of experts. They have gone directly to the public: Nuclear power – the energy balance.

A major thesis is that utilities are devoting tremendous energy to refining the uranium (but presumably don’t realize it or they would find economic alternatives). They argue the following:

• Rich ores are near exhaustion and the energy costs of lesser ores are enormous, indeed, they may be greater than the energy produced by the nuclear reactor.
• The “energy debt” to be paid for decommissioning nuclear power plants is significant.
• The energy costs of waste disposal are enormous.

I may have heard this argument only recently, but it’s been around long enough for knowledgeable people to respond.

Physicists from the University of Melbourne in Australia point out that the SLS paper produces energy assessments using theoretical relationships between money and energy, while other analyses use measured energy. The SLS paper assumes 30 times as much energy for building and decommissioning as is actually the case. The energy used at the Olympic Dam mine, according to SLS calculations, is more than the actual electricity production of south Australia. The Rossing mine, with its lower quality ore, costs more than $1 billion to operate yearly, according to SLS analysis, though the actual cost is less than $100 million. The SLS paper overestimates actual energy use by a factor of 80. See the whole article for more details. This group also addresses nuclear mistakes and proliferation.

There are a number of other analyses, see for example Nuclear Energy Institute.

The SLS site points to the World Nuclear Association.

I addressed earlier the question of whether there is Enough Uranium in slightly less detail but with a good reference.

The WNA and NEI sites are pro-nuclear sites, but they go through a review by people who appear to care about getting numbers right.

Occasionally there are questions as to whether estimates of greenhouse gas emissions include the total GHG emissions from mining to decommissioning and waste disposal. All (almost all?) analysis today for all activities is life cycle analysis, needed by governments and businesses to make valid choices.

According to the WNA site, GHG emissions from nuclear power are 2.7% those of coal power. The NEI site comes in around 2%. The analysis is for different countries.

Details on life cycle costs of driving in a future post.

Increasing Forest Fires

Sunday, September 10th, 2006

Over the last two decades (compared to 1970 to 1986), the number of major wildfires in the US West increased by a factor of 4, and the area of forest burned increased by a factor of 6. Canada has also seen an increase. Much of this increase was an abrupt change in the mid-1980s.

Political fights have centered on early Forest Service practices of controlling fires, and whether logging companies should thin the forests. A report in the August 18 Science, based on data from western fires, finds climate change to be the largest factor. This is especially true in the northern Rockies, which is seeing the largest increase.

This change has been dramatic. The number of days each year when fires burn (time from first discovered to last controlled) has increased by 78 days. The average large fire now burns 37.1 days, compared to 7.5 days before. The largest increase is in snow-dominated forests at elevations of about 2.1 km (1.3 miles).

Snowmelt provides 3/4 of western streamflow. There is low fire danger during periods of snowmelt and for about one month afterward. Unfortunately, snowpacks are gone one to four weeks earlier than 50 years ago, and streamflows peak earlier.

Data show that years with early snowmelt and a longer dry summer period have five times as many wildfires as years with late snowmelt. Forests that were once protected by late snowpacks, from elevations between 1.7 and 2.7 km (1 to 1.7 mile) are now seeing fires.

Warmer summer temperatures and reduced winter precipitation are associated with early melting of snowpack and so with increased numbers of large fires. In some forests (ponderosa pine), there is a smaller association with moist conditions before the hot summer, increasing the amount of combustible material available. Land use (extensive livestock grazing and effective fire suppression) in some areas, particularly California, may contribute to the increases in large fires.

Fires are much harder to put out. The 1988 Yellowstone Park fire lasted more than 3 months, burning more than 1.5 million acres. $120 million and 25,000 firefighters weren’t able to eradicate it. Finally the snows began in mid-September.

More than 95% of burned acreage comes from less than 5% of wildfires. A large wildfire can cost $20 million/day, and governmental agencies have spent $1.7 billion during fire season in recent years. Many years, damages in the West exceed $1 billion. Damages to natural resources are sometimes extreme and irreversible. And wildfires contribute to climate change.

Wildfires worldwide add an estimated 3.5 billion metric tonnes of carbon to the atmosphere each year. [This is about double the US contribution.] Where increases in wildfire are partly caused by land use, (very expensive) intervention can reduce the numbers and severity. In most of the West, this won’t work.

Spreading Bluetongue Virus

Saturday, September 9th, 2006

Bluetongue disease is a viral insect- borne infection of cows, sheep, goats, and deer, so named because one of the symptoms is a blue tongue from bleeding. It’s been spreading from Africa as European summers warm, arriving in Greece, Italy, Spain, Portugal and the Balkans since 1998. Beginning August 14, the virus has been found in the Netherlands, Germany, and Belgium. This year, Europe’s summer was hot; July was the hottest month on record in the Netherlands. Some scientists blame climate change for the spread of the virus.

Several details to be figured out, for example, the northern European virus resembles the Nigerian version, but there is not much trade in ruminants between the two areas. Hopefully a cold winter will kill off infected midges.

From the September 1 Science

Evolutionary Response to Rapid Climate Change

Friday, September 8th, 2006

The June 9 Science magazine has a perspectives article on what has led to changes in migration, development, and reproduction in numerous species as seasonal timing changes (spring begins earlier, winter later).

Phenotypic plasticity –

the ability of individuals to modify their behavior, morphology, or physiology in response to altered environmental conditions

explains some of the ability of species to respond to climate changes. Additionally, heritable genetic change is occurring in birds, squirrels, and mosquitoes.

Examples include earlier reproduction in Canadian red squirrels to take advantage of earlier spruce cone production. Blackcaps (birds) have a genetically distinct subpopulation which winters in Britain rather than Iberia. Another bird, the European great tit is moving its egg-laying date forward as caterpillars mature earlier in the year. North American mosquitoes that live in pitcher plants now initiate larval dormancy on days that are shorter, and the sun more southerly, than the cues from a few years ago, and take advantage of a longer growing season.

The genetic changes all relate to season:

earlier or more flexible timing of reproduction in squirrels and birds, later arrival of winter in mosquitoes, and a longer growing season for fruit flies.

Temperature change alone does not appear to be enough to cause a genetic response. Some of the new mosquitoes were moved to simulated new climates to test how they responded to various seasonal cues such as day length, and temperature, and temperature appeared not to be of great importance. Additionally, there appears to be no evidence of animals evolving for either greater heat tolerance of a higher optimal temperature. Part of the reason is that climate change is fastest in winter at high latitudes. [This article was published before this year’s long hot summer.]

Species show differing abilities to respond to climate change:

Small animals with short life cycles and large population sizes will probably adapt to longer growing seasons and be able to persist; longer life cycles and smaller population sizes will experience a decline in population size or be replaced by more southern species.

Four meter sea level rise

Thursday, September 7th, 2006

John Holdren, president of AAAS and prominent in climate change policy, predicted a possible sea level rise of 4 meters (13 feet) this century in a BBC broadcast last month. This prediction is much worse than fears expressed in May.

“We are not talking anymore about what climate models say might happen in the future.

“We are experiencing dangerous human disruption of the global climate and we’re going to experience more,” Professor Holdren said…

He blamed President Bush not only for refusing to cut emissions, but also for failing to live up to his rhetoric on harnessing technology to tackle climate change.

“We are not starting to address climate change with the technology we have in hand, and we are not accelerating our investment in energy technology research and development,” Professor Holdren observed.

Religion vs Science

Wednesday, September 6th, 2006

The United States is not the only country struggling with whether fundamentalists should be able to prevent publication of scientific discussions, with whether religion is the enemy of science. The July 21 Science looks at Picking a Path Among the Fatwas (AAAS membership needed):

Scientists in Iran find themselves challenged by true believers; some are trying to negotiate a peaceful compromise.

On one hand, a prominent Iranian sociologist, Ramin Jahanbegloo, was arrested for “contacts with foreigners” on his way to a Belgian conference, and was held without legal counsel in a prison notorious for torture. [He was released August 30 after a videotaped confession. There are several sites with more information, such as this Canadian one and this one from his colleagues at the University of Toronto.]

How should evolution be presented? Teheran’s Museum of Natural History begins with several glass cases showing traditional scientific evidence, a diorama depicting traditional scientific understanding, and one last display case with a couple of citations from the Koran and a poster from the Creation Evidence Museum in Texas.

On the other hand,

Iran is investing heavily in science now, after decades of neglect (Science, 16 September 2005, p. 1802). Even the Iranian supreme leader Ayatollah Ali Khamenei has issued a fatwa, or edict, calling on researchers to secure Iran’s position as the “leader in science” in the Middle East over the next 20 years.

According to the chancellor of the Tehran University of Medical Sciences, Bagher Larijani, brother of Iran’s nuclear negotiator,

“[Religious constraints are] a problem,” he says. “We scientists must approach [the religious leaders] very quietly and humbly to explain ourselves.” Larijani, an endocrinologist and Iran’s chief medical and research ethicist, says that such dialogues have already encouraged Iran to embrace research tools banned in other Muslim countries, including human embryonic stem cells and transgenic plants and animals. To meet Iran’s 20-year science goal, he says, scientific and religious experts must come together to work out their differences. Or, as Shiva Khalili, a psychologist at the National Research Center of Medical Sciences in Tehran puts it, “science and Islam must be harmonized.”

So even though constraints and self-censorship are problems (though not all Irani scientists agree), Iran is working on science questions that the current United States government finds exception to. [To be fair, much of the current difficulties experienced by American scientists are expected to disappear by January 20, 2009, or earlier.]

Religion and Science

Wednesday, September 6th, 2006

E.O. Wilson has begun a dialogue with Baptist pastors.

“Dear Pastor”, the self-described secular humanist begins in both his new book (The Creation: A Meeting of Science and Religion) and an article in the New Republic (A scientist’s plea for Christian environmentalism), we may not agree on everything, but where we agree, we can work together.

Many evangelicals have already begun to address what climate change will do to the poor, see especially the Evangelical Climate Initiative. But the effects on other species will be catastrophic as well.

I haven’t read the book yet, but can wholeheartedly recommend the article.

Pollinators in the UK and Netherlands

Monday, September 4th, 2006

In parts of Europe, extensive data exist on pollinators, provided by everyone from “Victorian vicars” to scientists. The July 21 Science magazine includes a study analyzing changes in their reported numbers since 1980.

Species richness on squares 10 km by 10 km in both the Netherlands and the United Kingdom were measured for both bees and hoverflies. In half of the UK cells, and 2/3 of Netherlands cells, there were significant losses in bee species. A tiny number of cells saw increases. There was also a decline in plant species that depend solely on bees for pollination. No one knows which came first.

Hoverflies fared better. In the UK, 1/3 of cells showed a loss of hoverfly species diversity, but 1/4 showed an increase. In the Netherlands, one in six cells lost diversity and one in three gained.

Especially hard hit were pollinators tied to a few plant species, with long tongues, with only one generation per year, or that don’t migrate.

In the UK, 75 wild plants depending on insect pollination declined, while 30 depending on wind or water increased. In the Netherlands, only bee-pollinated species declined.

Not only wild plant species suffer: agriculture depends in part on wild pollinators.

The UK and Netherlands have modified their landscapes extensively; in the latter, the entire landscape is considered artificial. These countries do have some of the best records, however. It is likely that pollinator loss, and the loss of plant species that depend on pollinators, is occurring worldwide.


Sunday, September 3rd, 2006

Los Angeles intends to plant one million trees, and expects to recoup $2.80 in energy savings, pollution reduction, storm-water management and increased property values for every dollar spent. A study from Lawrence Berkeley National Laboratory found that ten million trees in Los Angles, along with universal light-colored roofs and pavement, could lower peak summertime temperatures by five degrees.

Sacramento Municipal Utility District is providing up to 10 free trees per property (obviously, Sacramento lot sizes are larger than in Berkeley). They also supply expertise on tree planting and growing.

Though the effect is less dramatic in humid areas, Iowa has pushed private utilities to plant trees over the last 15 years.

There isn’t universal praise for the program. Some engineers are not used to thinking of trees as technology, and one third of residents in Sacramento see trees as work.

Let’s hope more utilities adopt such a program. The reduction in greenhouse gas emissions from air conditioning from city trees is more important than the carbon the trees absorb directly.

Find out more in the Washington Post article, Shade Crusade Takes Root.