Science – Page 84 – a sibilant intake of breath

Ice-free north pole in 2008?

Some scientists aboad the Canadian research icebreaker Amundsen are predicting that the North Pole may be ice-free for the first time in recorded history this summer. While this is not the same as saying the whole icecap will be gone, it does seem like the sort of thing likely to have symbolic resonance. At the very least, it becomes a bit harder to argue that no overall warming is taking place when huge chunks of the cryosphere start to vanish.

While there are good reasons to doubt whether this year will really see the pole bare, it is only really a matter of time:

[G]iven the rapid changes now evident in the Arctic, the ultimate fate of the North Pole—in fact, all permanent ice in the Arctic—may be all but assured. Almost all models have the Arctic completely ice free in the summer by 2100.

This raises some worrisome questions. If the sea ice is being lost at a greater rate than anticipated, is that likely to carry over to Greenland? If so, the optimistically low estimates for sea level rise published by the IPCC may prove grossly inaccurate.

CCS skepticism

The headline of a recent Economist article is one that policy-makers around the world should pay heed to: Carbon storage will be expensive at best. At worst, it may not work. There are two over-riding reasons for which the danger of a CCS-flop needs to be borne in mind:

First, many governments are assigning a big chunk of their planned emissions reductions to the new technology. If they find themselves in need of alternatives later, it may prove to be quite a scramble. Likewise, being able to ‘bank’ the CCS reductions now may make their plans seem both more viable and more certain than they really are.
Secondly, the very prospect of CCS is a lifeline to the coal industry. Power plants built to be ‘carbon capture ready’ may never do anything of the kind. If so, citizens should be even more concerned about the greenhouse gasses they are going to spew. Those financing the construction should also be wary, since carbon pricing is more likely than not to be on the way.

None of this is to say we shouldn’t welcome cheap, effective CCS if it does emerge. Not only could it allow the US and China to use their coal reserves while not wrecking the climate (local pollution is another matter), CCS coupled with biomass-fired generating stations could be carbon-negative.

Just don’t count those megatonnes before they’re buried.

Explaining greenhouse gases

Over at ScienceBlogs, Paul Revere has written a three part primer (one, two, three) about the physics of climate change. It begins with the nature of electromagnetism and moves on to discuss the energy relationship between the Earth, the sun, and outer space. It is the sort of thing that feels very basic, but which is nonetheless important to understand through-and-through. In particular, the explanation of black bodies in the second portion is clear and informative.

The discussion of Wien’s Displacement Law is also quite informative. The law holds that every object in the universe emits electromagnetic radiation, and that the most common frequency exists in relation to that object’s temperature in degrees Kelvin. To go from one to the other, divide 2898 by the temperature in degrees Kelvin. The quotient is the peak wavelength, expressed in microns. Human body temperature is about 310 degrees Kelvin, so our peak electromagnetic wavelength is about 9.35 microns long – in the infrared portion of the electromagnetic (EM) spectrum. Since we are pretty similar in temperature to the surface of the Earth, the wavelengths radiated by the planet are in a nearby portion of the spectrum.

It is is ability of greenhouse gases to absorb this infrared energy that lets them prevent energy from returning to space. They are transparent to the dominant wavelengths emitted by the sun, but opaque to those radiating from the Earth. Increasing their concentrations in the atmosphere (through fossil fuel burning, deforestation, etc), causes more of the energy that comes to the Earth from the sun to remain in the atmosphere. As a result of the extra energy, the temperature rises. Incidentally, this is also why people sometimes mention using ground-based mirrors to fight climate change. They reflect light at the same peak wavelength as that of the sun (which passes relatively unimpeded through the atmosphere). By re-radiating at that visible wavelength, rather than the infrared one favoured by greenhouse gases, the energy can be made to escape again. Of course, it would take a massive number of mirrors to balance out the effect of increased greenhouse gas concentrations on the EM emissions from all non-mirrored areas.

One upshot of understanding the nature of these gases is the ability to appreciate how their increased concentration simply must add more energy to our planetary system. The scientific questions that remain are about precisely what changes that energy will generate, and at what rate. The three posts are well worth reading in their entirety.

[Update: 17 December 2009] See also: Greenhouse gases other than CO2

Hansen on 350ppm

The most common position among climate change analysts is that we need to stabilize the atmospheric concentration of carbon dioxide somewhere between 450 and 550 parts per million (ppm). That is, for instance, the target range endorsed by Nicholas Stern. It is also thought by many to be compatible with the EU goal of generating less than two degrees Celsius of temperature increase, though that is only really plausible at the low end.

In recent Congressional testimony, James Hansen, director of the NASA Goddard Institute for Space Studies, argued that we actually need to cut concentrations from the present 385ppm to 350ppm or less. Basically, his argument is that even stabilization at the present level would have unacceptable consequences: both directly, in terms of impacts on physical and biological systems, and by kicking off feedback loops that will further worsen things. The distinction between the numbers may seem abstract to those not familiar with climate policy, but the practical differences between stabilizing between 550, 450, or 350ppm are massive. Each scenario requires that emissions peak at a different date, and that they fall more or less rapidly afterwards. Even staying below 450ppm requires that global emissions peak within 10-15 years, and that they fall to a small fraction of present levels by 2050.

If accurate, the 350ppm target invalidates a great deal of climate change planning. The general view is that we still have a cushion for additional emissions, to be split up between developed and developing countries. The former would lead the way, showing the latter how they can also do so once they reach a somewhat higher level of affluence. Getting back to 350ppm in a reasonable amount of time requires much more aggressive cuts, universally. It would also require that India and China move to a low-carbon economy long before any significant proportion of their population has reached Western levels of affluence.

Personally, I hope Hansen’s most recent testimony is not as prescient as that he gave twenty years ago. If we need to get the planet on a rapid path towards 350ppm, the disjoint between what is physically necessary and what is politically possible is far wider a chasm than has hitherto seemed to be the case.

Tomorrow’s electrical generation: distributed or concentrated?

There is an interesting debate ongoing on the Gristmill blog about whether the future of electrical generation lies primarily with big centralized power plants, like today, or with distributed systems.

Naturally, there are many factors that influence which is more attractive, many of which are regulatory rather than inherent to the physics or economics. I suspect the key dynamics will be the relative efficiency of differently sized facilities, the rate at which low-loss high voltage direct current (HVDC) transmission emerges, and the rate at which financing options for small facilities proliferate. Other important considerations will be the rate of improvement in the economics of solar photovoltaic systems, as well as the development and deployment of demand management and energy storage options for the grid.

In any event, it is doubtful whether one approach or the other will ever truly dominate. In all probability, a low-carbon society will incorporate both approaches in keeping with the strengths of different technologies and the needs of different areas.

The Botany of Desire

The Botany of Desire: A Plant’s-Eye View of the World tells the story of four plants and the desires they have gratified in people: the apple (sweetness), the tulip (beauty), marijuana (intoxication), and the potato (control). Each story is rich and fascinating; likewise, each has important lessons for appreciating the positon of humanity within nature, as well as the choices confronting us. This book has convinced me that I need to finish the business of reading Michael Pollan’s entire canon.

This book taught me quite a bit about agriculture, plant breeding, and genetics. The section on apples contains very interesting analysis on the differences between reproducing plants sexually (though seeds) or through cloning (with grafts). Similarly, the sections on tulips and marijuana say a lot about hybridization and the steady development of desirable traits. Finally, the section on potatoes confronts deep questions about the future of agriculture: most importantly, whether the monoculture can persist. Michael Pollan argues very effectively that the question “do we genetically modify plants or not?” is largely an extension of the question “do we continue to plant vast fields of clones?” The alternative – in terms of polycultures and local varieties – is especially interesting to consider in the face of a changing climate. It may be that the biotechnicians in lab coats will be able to develop new varieties that increase our resilience – enduring floods and droughts, etc. It is equally fair to suggest that a global agricultural system based around massive monocultures of just a few key species is especially vulnerable to disruption.

While this book raises deep questions, it is also charming and accessible. Pollan is especially gifted at conveying the eccentricities of some of the characters involved, as well as at inverting relatively familiar ideas into provocatively unfamiliar new forms. In particular, his discussion of intoxication accomplishes that – both in relation to the apple cider that was Johnny Appleseed‘s real gift to the American frontier and in terms of the myriad Cannabis sativa and indica hybrids that have emerged as ironic products of America’s drug war. Certainly, the book does a good job of advancing the hypothesis that domestication of plants was not a one-sided imposition. Rather, human history is deeply entwined with the history of the plants that have both nourished and manipulated us.

Overfishing and the EU

Long-time readers will remember the saga of the ‘fish paper’ – my research piece on the sustainability and legality of European Union fisheries policy in West Africa, eventually published in the MIT International Review.

Fisheries being an area of acute concern for me, I was gratified to see an unusually hard-hitting column in this week’s Economist about fish and the EU. It argues that EU goverments have shown “abject cowardice” in relation to their fishers for years. Meanwhile, overcapacity and unsustainable quotas have put the industry into a “suicidal spiral.” The article reports straightforwardly that: “More subsidies would reduce the already slim chance that Europe will ever have a sustainable fishing industry.”

I have argued previously that fishing should never be subsidized. There are far too many dangers of people selfishly exploiting a common good even without them. Indeed, I don’t have much hope when it comes to the long-term viability of world fisheries. That being said, if more people develop the understanding and candour displayed in this article, perhaps the madness can eventually be brought to heel.

Solar panels at 30 metres a minute

If solar photovoltaic power is going to emerge as a major source of electricity, it will be necessary to start manufacturing solar panels in a far more efficient and economical way. The model needs to shift from how glass was once made (as individual panels) to how it is now made (as a sheet being continuously produced and split at the cool end).

Nanosolar (a company mentioned here before) claims to have a process that will print solar panels onto aluminum backing at a rate of 100 feet per minute. Their hope is to eventually produce panels at a cost of $1 a watt and complete solar systems at $2 a watt – a price lower than that of coal-fired electrical capacity.

This is a goal in keeping with Google’s admirable RE < C project, which aims to displace coal with solar because the latter is cheaper, as well as far more environmentally benign.

Genetically modified potatoes

As is virtually always the case when reading Michael Pollan’s work, The Botany of Desire makes me want to share virtually every page and idea with friends. While a full review will have to wait, one thing that struck me while reading tonight is the situation with genetically engineered Bt crops, as discussed in the last section of the book.

Monsanto’s spuds

Bt is short for Bacillus thuringiensis: a soil bacteria that produces a poison that slays many crop-eating insects. Because it is naturally occurring, the bacterially derived poison is even permitted in many systems of organic agriculture. Genetically modified crops like Monsanto’s NewLeaf tomatoes have had the gene for the manufacture of the poison introduced into their own genetic material.

This is done in one of two relatively crude-seeming ways. Either the gene is inserted into a pathogen that is then allowed to infect the cells of the plant to be modified or DNA is literally shot into the target plant using a .22 caliber ‘gene gun.’ In most cases, the genes don’t end up in the right part of the target plant’s genome. In no cases do we comprehensively appreciate what kind of changes we are creating.

What we do know is this: when we create an environment where pests are exposed to a monoculture of Bt-generating plants, the pests will eventually evolve resistance. According to Pollan, Monsanto expect this to happen to Bt in about thirty years.

This is shocking when you think about it. Firstly, it reveals a kind of extreme short-termism in planning – the expectation that we can keep running on the treadmill and finding new solutions. Secondly, it reveals considerable unethical selfishness. Bt is used by many people other than Monsanto and Monsanto’s customers. The Bt-modified plants threaten to ruin the substance for everybody. Thirdly, it should be remembered that it is not only the resilience of the GM crops that may be undermined. Naturally occurring organisms defending themselves with Bt toxin and similar compounds may suddenly face invulnerable pests, with unknown consequences for nature.

Perhaps the most depressing thing about this section in Pollan’s book is the convincing argument that the above is actually an improvement over conventional potato production. To take the most egregious example, potatoes are regularly sprayed with an organophosphate pesticide called Monitor in order to kill aphids. This is because aphids carry a virus that gives potatoes brown spots inside. People don’t want to eat such potatoes, so farmers respond by spraying the plants with a substance akin to the deadliest of military nerve gasses.

The bigger picture

The more I read about energy usage, climatic science, agriculture, and fisheries, the more deeply green I become. It is pretty challenging to read something as compelling as Michael Pollan’s accounts of industrial agriculture and not begin to profoundly question the kind of soft-green liberal environmentalism that claims that there are just a few environmental externalities that we need to sort out before capitalism as practiced becomes sustainable.

P.S. Names like NewLeaf remind me instantly of Margaret Atwood’s excellent novel Oryx and Crake: essential reading for those trying to make sense of biotechnology’s brave new world.

Optical illusions

Optical illusions are an excellent way to prove that our visual perceptions are not simply the result of the pattern and nature of photons hitting our retinas. They prove that our brain makes big assumptions to simplify the task of understanding the world.

Here are two neat ones, from a blog that promises to post more:

At some previous point, I am sure I mentioned the compelling dragon hollow face illusion.