The environment – Page 167 – a sibilant intake of breath

Geography and the web

While it certainly doesn’t have the best name, the concept behind heywhatsthat.com is a neat one. Using data from Google maps, it generates panoramas as seen from mountaintops and other high places. You can then identify the mountains that you see around you.

The interface definitely needs some work, but the site does suggest ways in which openly accessible storehouses of data – such as the position and altitude information available from Google – can be combined into novel tools.

exploreourpla.net is a similarly badly named but interesting site. It combines geographic data and images related to climate change. You can, for instance, view a satellite map of Western Europe overlaid with luminous dots showing the most significant greenhouse gas emitters.

Big rocks in space

September 26th is the next full moon. That night, I recommend getting hold of a pair of field glasses and having a look at our closest significant stellar neighbour. In particular, note the large impact crater near the moon’s south pole. The Tycho Brahe crater was determined to be about 100 million years old, on the basis of samples collected by the Apollo 17 mission. While such craters soon fall victim to erosion from air and water on Earth, they are well preserved on the airless moon.

Such craters are not just of geological interest. They testify to the reality of impacts from comets and asteroids. A sufficiently large such strike could have devastating effects for humanity. In 2029, we will get a reminder of how close some objects are to hitting us, when the 99942 Apophis asteroid will pass so close to the Earth that it will be between communications satellites in geostationary orbits and us. For a while, this asteroid topped the Torino impact hazard scale. NASA estimates that the impact of Apophis would be equivalent to the explosion of 880 megatonnes of TNT: about 58,000 times the yield of the atomic bomb dropped on Hiroshima.

There is a small but real chance that the close pass of Apophis will alter its course such that it hits us on its next pass, in 2036. In response, a spaceflight subsidiary of EADS called Astrium is proposing a mission to learn more about the asteroid, study its composition, and investigate options for deflecting its orbit, if necessary.

In one sense, we are lucky with Apophis. It was discovered back in 2004 and has since had its orbit accurately tracked. A comet, by contrast, is essentially invisible until proximity to the sun causes it to melt and produce a tail. It is entirely possible that such an object could strike the Earth with little or no warning whatsoever.

Oceanic dumping of CO2

Carbon capture and storage (CCS) is a collection of technologies often mentioned in connection with global warming. Essentially, the idea is to capture the carbon dioxide emitted by things like power plants and then sequester it indefinitely in some sort of geological formation, such as a mined salt dome. While this idea is worthy of discussion in itself, my focus here is a number of approaches often described as CCS, but which do not achieve the same long-term result.

Some people have proposed that, rather than burying carbon underground, we just pump it into the sea. One option I am not going to discuss now is making big pools of liquid carbon dioxide in the very deep ocean. Rather, I will address the idea of using pipelines from shore or trailing from ships to release CO2 about 1000m down. Another alternative with similar effects is to make huge chunks of dry ice and throw them overboard, hoping most of the carbon will sink. Rather than being a type of CCS, these activities migtht be more accurately called ‘oceanic dumping of CO2.’

A matter of equilibrium

The problem here is both fundamental and intuitive. Think about a large plastic bottle of cola. With regards to the carbon dioxide, there is an equilibrium that exists between the amount dissolved in the liquid and the amount that is part of the air at the top of the bottle. As long as the system is closed (the cap is on), the amount of gas in air and water will trend towards that equilibrium point and, once the balance is achieved, stay there. This is what chemists mean when they say that equilibrium states display ‘constant macroscopic properties.’ CO2 from the water is still moving into the air, but it is now doing so at precisely the same rate as CO2 from the air is moving into the water. This is inevitable because if one rate were higher, the relative concentrations would change, and would continue doing so until the equlibrium was reached.

Now imagine that we change the equilibrium. If we take the cap off the bottle, the air inside mixes immediately with the air outside. Since the air inside has more CO2 than the air outside (because some of it has come out of the cola), this mixing causes the concentration of carbon dioxide at the surface of the cola to fall (we are ignoring the effects of atmospheric pressure in this analogy). As a consequence, the cola will start to release CO2, trying to get back to the old equilibrium between cola-dissolved and air-mixed gas. Since there is a lot more air, the equilibrium eventually reached will involve a lot less gas-in-cola. The cola goes flat. In the alternative, if we put a chip of dry ice into the cola and kept the cap on, a new equilibrium would eventually be reached in which both the cola and the air include a higher concentration of CO2.

Consequences

Dumping CO2 in the ocean thereby achieves two first-order effects. Firstly, it carbonates the sea, making it more acidic. Oceanic acidification is worrisome enough without such a helping hand. Secondly, it eventually results in an air-water balance of CO2 that is identical to the one that would have occurred if the CO2 started in the atmosphere. No matter which fluid it begins in, the same amount of CO2 at the same pressure will eventually result in the same balance between air-mixed and water-dissolved gas. It is just a matter of time. This is an important concept to understand, as it is the very heart of physical and chemical equilibria.

One big second order consequence results from this. If we do build such pipelines and do start carbonating the sea, people may decide that very carbon intensive technologies (such as coal generation or, even worse, Coal-to-Liquids) are environmentally acceptable. Using them in combination with oceanic dumping will inevitably have the same long-term atmospheric consequence as dumping the CO2 directly into the air.

Now, there is one reason for which oceanic dumping might be a good idea. Imagine there is some critical threshold for the atmospheric concentration of CO2: stay below it and things are reasonably ok, go above it and things all go wrong. In this scenario, it makes sense to store a bunch of CO2 and release it little by little. Of course, this only makes sense if we (a) only do this with CO2 we were inevitably going to release anyway (no new coal plants) and (b) aggressively cut future emissions so that the slow leak will not make us cross the threshold. Suffice it to say, this isn’t the kind of usage most advocates of CCS have in mind.

Precaution and bats

The ‘precautionary principle’ is frequently invoked in arguments about both security and the environment, but remains enduringly controversial. No matter how it is formulated, it has to do with probabilities and thresholds for action. Sometimes, it is taken to mean that there need not be proof that something is harmful before it is restricted: for instance, in the case of genetically modified foods. Sometimes, it is taken to mean that there need not be proof that something be beneficiail before it is done: for example, with organic foods. Sometimes, it has to do with who gets the benefit of the doubt, in the face of inconclusive or inadequate scientific data.

This article from Orion Magazine provides some interesting discussion of how it pertains to health threats generally, with an anecdote about rabid bats as an illustrative example.

I am not sure if there is all that much of a take home message – other than that people behave inconsistently when presented with risks that might seem similar in simple cost-benefit terms – but the article is an interesting one.

Truth in advertising

The kind of false environmentalism embodied in the Prius has been panned repeatedly on this site. Now, the government of Norway has decided that automobiles cannot claim to be “green,” “clean” or “environmentally friendly.” Bente Oeverli, a Norweigan official, explains that: “Cars cannot do anything good for the environment except less damage than others.”

Desalination

Water scarcity is a frequently discussed probable impact of climate change. As glaciers and snowcaps diminish, less fresh water will accumulate in the mountains during the winter; that increases both flooding (during wet seasons) and drought. Higher temperatures also increase water usage for everything from irrigation to cooling industrial processes. Given the extent to which the world’s aquifers are already depleted (see: Ogallala Aquifer), relatively few additional natural sources exist.

The big alternative to natural sources is the desalination of seawater. This is done in one of two ways: using multistage flash distillation or reverse osmosis. About 1,700 flash distillation plants exist in the Middle East already, processing 5.5 billion gallons of seawater per day (72% of the global total). These plants use superheated steam, a by-product of fossil fuel combustion, to pressurize and heat a series of vessels. As salt water flows into each successively lower pressure vessel, it flash boils. Condensers higher in the vessel cause the fresh water to precipitate out from the hot pressurized air solution. This is a simple process, but an energy intensive one.

Reverse osmosis, by contrast, uses a combination of high pressure pumps and specialized membranes to desalinate water. Essentially, the pressure drives fresh water through the membranes more quickly than the accompanying salts. As such, it is progressively less saline with each membrane crossing. In this process, there are both relatively high energy requirements (for high pressure pumping) and the costs associated with building and maintaining the membranes. Because it can be done at different scales, portable reverse osmosis facilities are the preferred option for combat operations or disaster relief.

Unfortunately, both processes are highly energy intensive. Particularly when that energy is being generated in greenhouse gas intensive ways, this is hardly a sustainable solution. Part of the solution is probably to sharply reduce or eliminate water subsidies – especially for industry and agriculture. More transparent pricing should help ensure that the whole business of desalination is only undertaken in situations where the need for water justifies all the expenses incurred.

Scottish renewables

When thinking about a general trend – such as increasing the usage of renewables for electricity generation – it is often helpful to consider a case study. Wikipedia’s article on renewable energy in Scotland makes for an interesting read.

Hydrogen and AAs

At a party this weekend, I had a conversation with someone who believed that the energy needs of the future would be solved by hydrogen. Not hydrogen as the input for nuclear fusion, but hydrogen as a feedstock for fuel cells and combustion engines. It’s not entirely surprising that some people believe this. For years, car companies have been spouting off about hydrogen powered vehicles that will produce only water vapour as emissions. The Chevron game mentioned earlier lets you install ‘hydrogen’ electricity generating capacity. The oversight, of course, is that hydrogen is just an energy carrier. You might as well say that the energy source of the future will be AA batteries.

AA batteries are obviously useful things. They provide 1.5 volts of power that you can carry around with you and use to drive all manner of gadgetry, but they are hardly an energy system unto themselves. The chemicals inside them that create their electrical potential had to be extracted, processed, and combined into a usable form. Inevitably, this process required more energy than is in the batteries at the end. The loss of potential energy is a good trade-off, because we get usable and portable power, but there is no sense in which we can say that AA batteries are an energy system.

A similar trade-off may well eventually be made with hydrogen. We may break down hydrocarbons, sequester the CO2 produced in that process, and use the hydrogen generated as fuel for cars. Alternatively, we might use gobs of electricity to electrolyse water into hydrogen and oxygen. Then, we just need to find a way to store a decent amount of hydrogen safely in a tank small, durable, and affordable enough to put in vehicles; build fleets of vehicles with affordable fuel cells or hydrogen powered internal combustion engines; and develop an infrastructure to distribute hydrogen to all those vehicles.

When you think about it, hydrogen seems less like a solution in itself, and more like the possible end-point of solving a number of prior problems. As far as ground vehicles go, it seems a safer bet to concentrate on improvements to rechargeable battery technology.

Gore’s ten points

Al Gore has recently presented a ten-point plan for the United States to deal with climate change over the course of the next few decades:

An immediate “carbon freeze” that would cap U.S. CO2 emissions at current levels, followed by a program to generate 90% reductions by 2050.
Start a long-term tax shift to reduce payroll taxes and increase taxes on CO2 emissions.
Put aside a portion of carbon tax revenues to help low-income people make the transition.
Create a strong international treaty by working toward “de facto compliance with Kyoto” and moving up the start date for Kyoto’s successor from 2012 to 2010.
Implement a moratorium on construction of new coal-fired power plants that are not compatible with carbon capture and sequestration.
Create an “ELECTRANET” — a smart electricity grid that allows individuals and businesses to feed power back in at prevailing market rates.
Raise Corporate Average Fuel Economy (CAFE) standards.
Set a date for a ban on incandescent light bulbs.
Create “Connie Mae,” a carbon-neutral mortgage association, to help defray the upfront costs of energy-efficient building.
Have the Securities and Exchange Commission require disclosure of carbon emissions in corporate reporting, as a relevant “material risk.”

A much more detailed discussion of the points can be found on Grist. It is safe to expect considerable elaboration in Gore’s upcoming book: The Path to Survival. It will be available as of Earth Day (April 22nd) of 2008.

It is an interesting – and distinctly American – mix. It seems like number one is the uber-recommendation, while the others are more specific subsidiary policies. Exactly how such a freeze could be implemented – politically, economically, and legally – is a massive question. That said, it is a list that targets many of the major opportunities for domestic emission mitigation. It will be interesting to see whether any of these get the endorsement of Democratic or Republican candidates in the run-up to the 2008 Presidential election. If so, it will make for a big break with past half-hearted and voluntary measures.

PS. Those unfamiliar with the American mortgages will understand number nine better if they read about Fannie Mae and Freddie Mac: America’s huge and bizarrely named quasi-government-backed mortgage corporations.

Passivhaus

There has been a lot of talk lately about compact fluorescent light bulbs. Huge billboards of David Suzuki looking like a genie, with a glowing CF bulb floating above his hand, dot the landscape. While these bulbs are a lot more efficient, they aren’t likely to make a huge difference in the long run. Arguably, it would be better to focus on encouraging the building of passive houses, which require no energy for heating, rather than making marginal improvements in existing dwellings. It may be entirely desirable to do both, but when it comes to finding a symbolic signal issue to rally around as energy conservationists, the latter option is a lot more impressive.

To qualify as a passive house, a building must use less than 15 kWh per square metre per year for heating. That works out to less than $1 per square metre at current energy prices in Ontario. Total primary energy usage for such houses (heating, hot water, and electricity) is not to exceed 120 kWh per square metre per year. The technology to do this isn’t absolutely cutting edge: a passive house has been continuously inhabited in Darmstadt since 1991.

Apparently, building super-insulated houses with the ability to heat and cool themselves using just the ambient light and heat in their surroundings does not cost significantly more than building ordinary houses (though it requires different materials and more expertise). Given how virtually none of them exist in North America, it seems fair to say that consumer demand – even with high energy prices – is not sufficient to drive a large scale shift.

A number of different policies could help boost adoption: municipalities could require that a certain proportion of commercial and residential buildings constructed be passive in this way, subsidies or tax breaks could be given to firms that choose to employ such construction methods, and so forth. At the very least, government could make a concerted effort to do most of its own building in this way.

Masses of additional information is online:

As environmental statements go, building or living in such a house is probably much better than driving a Prius.