Science – Page 108 – a sibilant intake of breath

Films and fish stocks

According to Shifting Baselines, it seems that Charles Clover’s excellent book “The End of the Line” is being made into a documentary film.

That was the book that inspired me to go meet Dr. Daniel Pauly at the UBC Fisheries Centre, as well as go on to write the article that was recently published in the MIT International Review.

Hopefully, the release of the film will raise the profile of the issue a bit. As morally dubious as the factory farming of land animals is, it does not endanger the survival of these species. That is not true of the modern industrialized fishing industry. The collapse of fisheries in the Mediterranean and North Atlantic is just a sign of what is to come to all fisheries worldwide unless aggressive conservation measures are put in place and enforced.

Chronic disease worldwide

People tend to think of heart disease and cancer as the diseases of the rich world, while AIDS, malaria, and tuberculosis afflict the poor. The latter idea is certainly true: among those, only AIDS kills an appreciable number of people in rich states (though antibiotic resistant tuberculosis may start changing that).

Just because infectious diseases tend to kill a lot more people in poor states than in rich ones, it does not follow that infectious diseases are the greatest health threat there. According to the World Health Organization, heart disease and cancer kill more people in poor states, as well, and together cause 45.9% of all global deaths. Add in diabetes and other chronic diseases, and you find that 63.5% of all deaths are caused by chronic diseases, compared with 29.7% for all infectious diseases (injuries kill 9.3%).

A forecast for the period between 2006 and 2015 predicts that deaths from infectious diseases will fall by about 4% in poor countries, while deaths from chronic illnesses will rise by about 20%. Partly, this is the result of growing affluence – particularly the ability to afford cigarettes. People in China, Russia, and Indonesia already spend between five and six percent of total household income on cigarettes.

The Millennium Development Goals include two targets relating to infectious diseases:

Halt and begin to reverse the spread of HIV/AIDS
Halt and begin to reverse the incidence of malaria and other major diseases

While these are obviously worthy and important goals, there is a danger of funds not being well matched to where they can do the most good. Shedding a few misconceptions about the relative health challenges of rich and poor states may help avoid that. So too, the further recognition that lifestyle factors like diet, exercise, and smoking have an enormous influence on overall morbidity and mortality.

McIntyre and NASA data

There is a lot of talk in the media about how Steve McIntyre – an amateur scrutineer of climate statistics – found an error in data released by NASA. Specificically, it was mistankingly believed that data that had not been corrected for urban heat effects had been. This data pertains only to the United States and the correction implies that about 0.15 ºC of the observed warming there was just a statistical error. In itself, this would not get much attention. What does get attention is that this changes the rankings of the hottest recorded years in the United States. Rather than 1998 being the hottest recorded year in the United States, 1934 now wins. Many news sources are treating this data revision as though it demonstates a serious flaw in the overall quality of our climate understanding.

The Fourth Assessment Report of the Intergovernmenal Panel on climate change is based on a far broader collection of data than just NASA data pertaining to just the United States. As such, their overall conclusion that is barely affected by this change. Likewise, the worldwide figures for hottest years still cluster in the last decade. The report’s Summary for Policy Makers explains:

Eleven of the last twelve years (1995–2006) rank among the 12 warmest years in the instrumental record of global surface temperature (since 1850). The updated 100-year linear trend (1906 to 2005) of 0.74°C [0.56°C to 0.92°C] is therefore larger than the corresponding trend for 1901 to 2000 given in the TAR of 0.6°C [0.4°C to 0.8°C]. The linear warming trend over the last 50 years (0.13°C [0.10°C to 0.16°C] per decade) is nearly twice that for the last 100 years. The total temperature increase from 1850–1899 to 2001–2005 is 0.76°C [0.57°C to 0.95°C]. Urban heat island effects are real but local, and have a negligible influence (less than 0.006°C per decade over land and zero over the oceans) on these values.

This information is based on a broad collection of sources including satellites and ground stations around the world. It also incorporates evidence from ice cores and other historical indicators of temperature and greenhouse gas concentrations. What the McIntyre situation demonstrates is the degree to which perceived anomalies are seized on by people with pre-determined agendas to either support or refute the overall climate change consensus. While the data is not a statistical threat to that consensus, it does have the ability to foster doubt in the general public and among policy-makers, especially when presented out of context.

Having people out there scrutinizing the data is excellent, and a good check against the proliferation of misleading information. At the same time, it is necessary to be rigorous in our thinking about how one new piece of information affects the overall picture. Likewise, it is important to remain aware of the degree to which individual agendas influence how information is processed, and what responses it evokes.

Hollywood physics

Deficiencies in movie physics can be good fun to dissect and mock, but a recent paper suggests that they are less benign. “Hollywood Blockbusters: Unlimited Fun but Limited Science Literacy” suggests that the absurdities that abound in popular films actually weaken the people’s ability to understand how the world works. The paper concludes that:

Hollywood is reinforcing (or even creating) incorrect scientific attitudes that can have negative results for the society. This is a good reason to recommend that all citizens be taught critical thinking and be required to develop basic science and quantitative literacy.

Specific issues discussed in the paper include projectile motion, Newton’s laws, impulse, buoyancy, and angular momentum. Certainly, some films underplay the dangers of high falls and similar phenomena – as well as playing up the dangers of things like automobiles spontaneously exploding.

Personally, I would prefer a world in which movies portrayed all the sciences in realistic and accessible ways. Unfortunately, such films are in perpetual danger of being ignored in favour of flashy absurdities like the The Core or the egregious recent Star Wars films.

Reading these entertaining reviews is a good after-the-fact vaccine.

Ravenous pine beetles

According to an interview with the CBC given by Allan Carroll at Natural Resources Canada, there is not much hope of British Columbia containing the mountain pine beetles (Dendroctonus ponderosae) that have already killed 9.2 million acres of forest. He said that “Our estimates are that by about 2013 to 2015, the beetle will have killed about as much as 80% of the mature pine in the province and I don’t think we can really affect that now.” As the supply of Lodgepole Pine becomes eliminated, the beetles sometimes move on to Spruce and other species. If the beetles begin to target the Jack Pine of the boreal forest, Carroll says that it “could wipe out billions of trees all the way to the East Coast.”

These insects were mentioned here before, in the context of the effect of changing minimum temperatures on species ranges. Apparently, once they have reached their maximum cold tolerance, these beetles can endure temperatures of -40°C. It is significant cold events in the early and late winter – before their chemical defences have fully come on stream – that can lead to “very large amounts of mortality in the [beetle] population.” A few very crisp fall days would do a lot for western Canada’s forests.

The acid sea

One frequently neglected consequence of rising global concentrations of carbon dioxide is increasingly acidic oceans (though it has been mentioned here before). Since the Industrial Revolution, the world ocean has absorbed about 118 billion tons of anthropogenic CO2: half of total human emissions. Every day, another 20-25 million tonnes are being absorbed.

Before the Industrial Revolution, oceanic pH was about 8.179. Now, it is at 8.104. By 2100, it is projected to be 7.824. Because pH is a logarithmic scale, that is a bigger change than it seems to be. At the projected 2100 concentration, the shells and skeletons of corals, molluscs, and phytoplankton with aragonite shells begin to dissolve within 48 hours. James Orr et al, writing in Nature provide many more details:

In our projections, Southern Ocean surface waters will begin to become undersaturated with respect to aragonite, a metastable form of calcium carbonate, by the year 2050. By 2100, this undersaturation could extend throughout the entire Southern Ocean and into the subarctic Pacific Ocean. When live pteropods were exposed to our predicted level of undersaturation during a two-day shipboard experiment, their aragonite shells showed notable dissolution. Our findings indicate that conditions detrimental to high-latitude ecosystems could develop within decades, not centuries as suggested previously.

The effect of more acidic oceans on aragonite is part of why the Stern Review projects that coral reef ecosystems will be “extensively and eventually irreversibly damaged” at less than 450 ppm CO2 equivalent and less than 2°C of warming. Given how critical coral reefs are to overall oceanic ecosystems – including key commercial fish species – this should be of concern to everyone.

It is very hard to project what the consequences of all this will be. As with so many other climatic phenomena, the net impact for human beings probably has to do with the relative strength of positive and negative feedbacks and the corresponding resilience of ecosystems. What is certain is that the only way to prevent acidification is to signficantly cut CO2 emissions.

Heat: How to Stop the Planet from Burning

During the past two years, I have been reading about climate change for several hours every day. During that span of time, I have read dozens of books and hundreds of articles. Quite possibly, none were as thought-provoking as George Monbiot’s Heat: How to Stop the Planet from Burning. If you are at all serious about understanding the issue of global warming, it is essential reading. He may not be right (indeed, it would be far preferable for him to be wrong) but he will definitely make you think.

His project is an ambitious one. Having decided that global temperatures must not be allowed to rise by more than 2°C on average, he works out what that would mean for Britain. Since British emissions per capita are way above the world average, a fair system would require much heavier cuts there than elsewhere. Canada’s per-capita emissions are even worse.

Here is a smattering of what he says will be required by 2030:

A power grid dominated by renewables and natural gas plants with carbon capture and storage.
Dramatically, dramatically tightened building regulations – making most houses either ‘passive’ in their non-use of heating or cooling or capable of producing their heat and power from piped-in hydrogen, possibly supplemented by solar.
Most private automobile travel replaced by a buses or non-motorized transport, both within and between cities.
An end to cheap air travel: no more low cost flights, with massive total cuts in the number of both short and long-haul flights.

The last is the result of a complete lack of alternative technologies that can deliver the kind of emission reductions required. Even if all other emissions were cut to zero, growth in air travel would make that one sector break his total limit by 2030.

Suffice it to say, Monbiot is not in the main stream of this debate. The Stern consensus is that climate change can be dealt with at moderate cost. Even if Monbiot’s ideas are entirely possible, in terms of engineering, one cannot help but doubt that any political party in a democratic state could successfully implement them. The impulse to defend the status quo may turn him into a Cassandra.

In fifty years, it is possible that people will look back at this book and laugh. Alternatively, It may be that they look back on Monbiot as one guy who had approximately the right idea while everyone else (Gore and company included) were in denial. The answer seems to depend upon (a) whether emissions need to be cut as much and as quickly as he thinks and (b) how bad it will actually be if they are not. It is pretty easy to do the math on the first of those, at least for any desired greenhouse gas concentration or temperature change. The latter is harder to assess. Regardless of which proves to be closer to the truth, this is a book I wholeheartedly endorse for anyone trying to keep abreast of the climate change issue.

Peak power, storage, and renewables

One characteristic of electricity poses severe challenges both for the drive towards lower carbon emissions and towards more power based on renewables: the fact that supply must precisely match demand at all times. On account of this, power plants are divided into two categories – base plants, which constantly provide the amount of power normally demanded by homes and businesses, and peaker plants, which provide some extra juice when everyone decides to turn on the air conditioning at once.

The first reason this is a problem is that peaker plants are much less efficient. It is costly to build an efficient oil or gas plant, and it just isn’t worth it to do so for one that runs relatively rarely. The second problem is more to do with the inconsistent nature of renewable power; the wind does not always blow and the sun does not always shine. As such, we need enough on-demand energy (usually based on fossil fuels) to fill the gap between what windmills can produce at time X and what consumers demand then. Plants on standby may not use much fossil fuel, but maintaining and operating them uses resources in a way that makes renewable options less appealing than otherwise.

The answer is obviously energy storage. We can build dams with two reservoirs, one uphill from the other. When power is in excess, we can pump water from the low reservoir to the high one. It can then be passed through turbines at times of peak demand to recover energy. Apparently, this can be done with efficiency of about 85%. Other options along these lines would be to have clusters of offshore wind turbines that use electrolysis to make hydrogen from seawater. That can be piped or carried to shore and used to produce carbon-free energy.

To me, it seems like another option is to use technology and incentives to help moderate power demand. If there are industries that can use a lot of power or a little, switching easily, then should be encouraged to become part of the swing capacity. It may even be worthwhile to store energy as heat in sinks or as kinetic energy in flywheels. If houses could heat or cool a block of material at the time when power is cheapest, then use that potential for heating or cooling across the day, we might need less peak capacity.

Some kind of competition for inventing fossil-fuel-free peak-power solutions may well be in order. If the technology exists, and there is enough of a cost differential between times of highest and lowest demand, it may well transpire that infrastructure can be built to normalize power demand on the scale of days, or even weeks.

The Khazzoom-Brookes Postulate

Reading through George Monbiot’s Heat, I encountered the idea of the Khazzoom-Brookes Postulate for the first time. The postulate relates to the effect of increasing energy efficiency on total energy usage and holds thas as the energy efficiency of industrial processes increases, total energy use actually rises as well. While initially counter-intuitive, the idea does seem to have some validity. If the energy cost of producing one tonne of aluminum falls from $5000 to $4000, you would expect aluminum companies to produce more. After all, their profit margin will have widened, all else being the same. The Celsias blog cites another example: if Boeing’s new 787 Dreamliner is 20% more fuel efficient, that just means that ticket prices will fall and more people will fly. Greenhouse gas emissions will stay the same or rise.

As Monbiot acknowledges, the postulate is controversial. It is certainly decidedly inconvenient for all the people who trot out ‘increased energy efficiency’ as the first (painless) means to combat climate change. Increased energy efficiency may be great for various reasons of convenience and enjoyment, but the postulate and accompanying logic does give one reason to doubt whether it can have a positive effect on reducing greenhouse gas emissions.

Sustainability and the Prius

One way or another, the Toyota Prius. is a symbolic vehicle. For some, it symbolizes how saving the planet can be relatively painless, enjoyable, and hip. You still get the same basic thing (the ability to zip around in a car) but without the guilt and with the important ability to lord it over the less environmentally responsible. Alternatively, the Prius is a symbol for the superficiality of the environmental commitments most people are willing to make. Seen in this way, it reveals how environmentalism is mere tokenism in many cases.

There are two arguments here which frequently become confounded. One is a first-order question about the ultimate sustainability of different energy systems. Is it sustainable to run internal combustion cars using cellulistic ethanol? What about plug-in hybrids charged using big nuclear fission plants? The answers to these questions are ultimately knowable to a high degree of specificity. For any given level of technology, answering them is simply a matter of applying chemistry and physics. The uncertainty therefore lies in estimations about what will be technologically possible at X or Y time.

The second-level argument is much more heuristic and intractable. There is the fundamentally liberal belief that environmental problems can be tackled fairly painlessly through a bit of cleverness and some new hardware. This is a view that takes the Prius as a positive symbol. At the other extreme is the conviction that only massive sacrifice can generate sustainability. The vision in Fight Club of people in rags pounding strips of leather on an abandoned superhighway captures this, and adherents would surely dismiss the Prius as a pathetic fig-leaf.

The latter argument seems to generate a lot more heated discussion, largely because the real meat of analysis on the former question lies in territory where most people cannot hold their own (who reading this could really calculate the efficiency of an energy grid based on photovoltaics, or of an industrial process for ethanol production from cellulose?). The latter debate requires only a will to participate, though it may not do much to leave us with an understanding of which view of the Prius is justified.