Tuesday, November 04, 2003
But if it comes true, is it still satire?
Overzealous Simpsons fan Rob Baur has grafted a tomato to a tobacco and produced real tomacco. (But surprise: no radiation seems to have been used!) Shades of Eugene Scheiffelin?
Thursday, October 30, 2003
Head in sand
Today, in a 55-43 vote, the Senate rejected McCain and Lieberman's modest bill to reduce industrial (but not vehicular) CO2 emissions to 2000 levels by 2010. Why? Because, according to Sen. Larry Craig (R-ID), (a) the bill would require the introduction of a "massive new regulatory process," and anyway, (b) CO2 "is not a pollutant. It does not represent a direct threat to human health."
Okay. The massive regulatory process is beyond my expertise, but is that true? As I understand it, the bill would have allowed companies to trade emissions rights on the free market -- every Republican's favored method of maximizing economic efficiency while minimizing bureaucracy. And it's not like we're not already monitoring industrial CO2 and other emissions.
As for CO2 not being a pollutant, I thought I'd already laid that sort of idiocy to rest, and I'm dismayed to discover that there are US Senators who aren't reading my blog as carefully as they should. Craig's not the guy who gets to decide what's a pollutant and what's not. By asserting that it's not, he's implying that the nature of things is simple and accurately reflected in the common sense of ordinary folk.
The thing is, he implies this while appealing to climate change's complexity:
Given the uncertainties about the timing, pace, and magnitude of global warming projections and the imprecise nature of the regional distribution of possible climate changes, and recognizing the complex feedback mechanisms within the climate system that could mask, mimic, moderate, amplify, or even reverse a greenhouse-gas-induced warming, the question is posed: What policy response, if any, are indicated, now, or in the future?He can't have it both ways, and given the articulateness of his appeal to complexity (which I ultimately disagree with), I interpret Craig's cynical claim that CO2 is not a pollutant as a bone he's throwing to what he believes is a less-than-sophisticated constituency.
Tuesday, October 28, 2003
Out the tailpipe
Jeffrey Dukes of UMass Boston has estimated how much primary productivity is burned up in the form of fossil fuels. From an article in The Economist summarizing an article to appear in the November issue of Climatic Change:
[Dukes] calculates that the fossil fuels burned in 1997 were ultimately derived from 400 years' worth of “primary production”, as the organic material produced by photosynthesis is known technically.Okay. Now my car gets thirtysome mpg, which translates to how many thousands of hectares of ancient forest?
...[Dukes] calculates that completely replacing 1997's fossil-fuel consumption with fuels derived from biomass would use up almost a quarter of the Earth's primary production.
Wednesday, October 22, 2003
It's what SEPTA, our unfortunately acronymmed regional transit agency, calls Slippery Rail Season. Trains are frequently up to fifteen minutes late because of leaves on the rails -- and apparently it's not just a local problem. The Guardian (yes, the UK one) explains it like this:
Leaves on the line are a problem that affects all countries with deciduous trees, and no universal solution has yet been found. The phenomenon occurs because the train wheel exerts 40lbs per square inch of pressure on the rail, generating heat, which bakes the lignin in the leaves on to the rail so firmly that it would take a knife to scrape them off. This "black ice" of the rails means trains lose traction and braking ability and can overshoot signals and stations.What's one difference between here and there? In Britain they use satellite data and high-tech sand-gel mixtures -- and remove trees -- to keep the rails grippy. In southeastern Pennsylvania we grumblingly accept the delays and station overshoots ("Too bad, we just rolled past Overbrook!") as another feature of autumn.
(Thanks to Crooked Timber for the link.)
Friday, October 17, 2003
China: GM-food haven
From Bob Park's What's New:
According to a Chinese news agency, Yang Liwei carried a bag of vegetable seeds into space. There have been stories coming out of China for several weeks that exposure of seeds to space radiation produces huge tomatoes and other vegetables. When it was pointed out to the news agency that most mutations are harmful, WN was assured that in China the radiation effect is always positive, leading to bigger and better vegetables that will revolutionize agriculture.Mmmm: tomacco.
Thursday, October 16, 2003
The High Line
This abandoned elevated-train structure could soon become a new kind of urban park. Turning old rail lines into parks is not a new idea, but The High Line has the distinction of being (a) very urban, (b) elevated, and (c) an opportunity to apply some radical design-thinking.
Friday, September 26, 2003
Workweek climate effect
Temperature fluctuates more during the workweek than during weekends. This according to a PNAS paper summarized in this news brief in Scientific American. Odd thing:
The direction of the effect was not always the same, however. Some cities (particularly those on the coast) exhibited higher [diurnal temperature ranges, or DTRs] on the weekends than during the weeks, whereas many in the midwest showed smaller DTRs on the weekends. Outside of North America, the magnitude of this weekend effect is smaller, Forster and Solomon report, with cities in Japan and China showing the largest swings.What's going on on the coasts??
Tuesday, September 23, 2003
How many leaves on a clover?
New Scientist has a fun Q & A section called "The Last Word". Here's a collection of "Last Word" columns on plants.
Tuesday, September 16, 2003
A note about comments
I use Blogspeak for comments. Blogspeak is switching servers, and I've been warned that some comments to my blog may be lost. If you don't see your comment, please re-post it.
knowledge + ignorance = ignorance?
Back40 accuses me of underestimating the state of scientific ignorance about the processes driving and possibly mitigating climate change. He claims to have "a more realistic and intellectually honest evaluation of the state of the art" than I do, and he counters my list of consensus points:
Well, he's sort of right (and so I must have been being intellectually dishonest!): we don't know absolutely everything.
- We do not know what's happening to the earth's climate. We have some theories based on sparse data but don't know much at all.
- We do not know that the accelerating conversion of fossil fuels into carbon dioxide is a major cause. We suspect that increases in GHGs are the result of human activity, there's strong correlation, but we don't know which activities are to blame or to what extent.
- We do not know that enormous changes in the earth's energy balance, hydrologic cycles, climate, and ecosystem function must result. We know so little about any of these systems that it's humbling.
I'm not prepared to engage in the sort of argument in which Back40 and I assert different degrees of scientific certainty and different threshold levels for action. I'll just make two points. First, and maybe I didn't make this point clearly before: it's not a real argument (and so it's a rhetorical trick) simply to assert the importance of a known countervailing factor. The factor's mere existence doesn't negate the trend in question unless you've done the math. Back40 hasn't done the math (or hasn't shown us his math), and in fact most of the math that has been done shows that carbon-enriched productivity does very little to counter the accelerating accumulation of carbon dioxide in the atmosphere. (Also that reflectance from clouds doesn't decrease by enough the energy input to the earth, though that math turned out to be one of the bigger challenges for climate modelers.) Now, maybe Back40 doesn't trust modeling to give us real knowledge -- he'd be far from alone. If that's the case, then that should be his argument. He should dispute the validity of the claims rather than imply that the countervailing factors are completely unexplored territory. (Full disclosure: I'm an ecological modeler by profession -- just not a climate modeler.)
Second point: it is a rhetorical trick simply to point out the existence of knowledge gaps (because it's true that we don't know 100% to 100% certainty) without acknowledging that action would be called for even if the state of our knowledge and certainty are somewhere less than 100%. Back40 is clearly a smart enough thinker to agree with me at least on this point: at some point action -- even sweeping, costly action -- becomes appropriate even if it can be argued that we don't understand everything about the earth's energy balance.
I think that Back40 agrees with me that we have a lot of knowledge with a lot of certainty. (He rightly takes me to task for ignoring his reference to the "library of books" of knowledge we do have.) He and I disagree on the political importance of how much ignorance is left. The problem is that ignorance and knowledge don't add up to some finite amount of potential knowledge -- it's not like a gas tank, in which all we have to do is replace the empty space (ignorance) with gas (knowledge) until the needle reaches F. The supply of unanswered questions is infinitely large. To make political change contingent on our ignorance dipping below some threshold level -- that is, to allow what we don't know to nullify all we do know -- is to choose never to make political change.
It's important that the debate focus on the claims that climate scientists have made, including those that have been made regarding countervailing factors. (As Back40 says, "stick to the knitting.") The "library of books" makes a case -- a very strong one, in my opinion and in the opinion of most ecologists and climate scientists -- and if that case is to be attacked it should be attacked on its substance (e.g., the vegetation-enrichment models used unrealistic simplifying assumptions) rather than simply dismissed (e.g., "We have no idea what the consequences of elevated atmospheric CO2 will be"). Back40 and I will probably continue to disagree -- he and I might want to act on different certainty thresholds, say -- but I promise to respect his arguments if he stops throwing away all the knowledge that my colleagues and I have succeeded in building thus far.
Final, admittedly petty note: Back40 writes:
Ted may not be aware of this though since he says "which most general readers don't understand in its [climate change] full complexity." Apparently he is under the impression that someone does understand climate change in its full complexity.The insertion in square brackets is Back40's, and misleading: what I'd written was that most readers don't understand the issue of climate change in its full complexity. I'd assert that there are plenty of scientists, politicians, economists, and other environmental professionals who spend their careers juggling all the complexities of the climate-change issue, and for me that's close enough to full understanding. My use of its may have been ambiguous, but since the whole post was about rhetoric and not about science, it should've been somewhat clear. It's true that it's arguable that fully understanding the political issue of climate change would include a full understanding of climate change itself. I personally would argue that the political issue is all about the perceived scientific uncertainties, as well as the fog of rhetoric used on all sides of the debate.
Monday, September 15, 2003
Like, your employer bought that computer so you could read blogs?
Tired of finding aliens with your spare processor time? Predict changes in the climate instead.
When one biosphere just isn't enough
Biosphere 2 is now on the market. Anyone up for splitting rent?
Thursday, September 11, 2003
Complex = completely beyond human understanding?
A useful rhetorical trick: you take a difficult issue -- like climate change -- which most general readers don't understand in its full complexity. You play up its difficulty -- and then you argue that because there's so much we don't understand, we would be hasty to act. Crooked Timber's Chris Bertram describes this trick's effectiveness in a recent discussion of the climate-change discourse:
I try to make up my mind on the issue by reading the papers and magazines, watching the TV, and so on (like pretty much everyone else). Mostly, I think that the conventional view is probably right, but sometimes I can be shaken into thinking that maybe no-one has good reason to think any particular thing on this subject. When I’ve been thus shaken into a state of epistemic indifference, I also, naturally, become less supportive of pollution-limiting initiatives. Even if the anti-greens haven’t won the argument at that point, they’ve achieved a good part of their purpose as lobbyists.The trick is a classic -- tobacco growers and marijuana enthusiasts (to name one botanical interest group on either side of the political center) have used it for decades -- and judging by how many intelligent, informed thinkers (and voters) still believe that anthropogenic global warming is a controversial hypothesis, it's effective as well.
Why is it a rhetorical trick and not a valid argument? Two reasons: (1) it's a faulty kind of argument to make. Arguing that because A hasn't been proved we must believe B is a form of argumentum ad ignorantiam, or maybe of argument by shifting the burden of proof. But even if there weren't a logical fallacy being committed (after all, I don't want to appeal to the fallacy fallacy), the argument still wouldn't stand: (2) we do know what's happening to the earth's climate. After decades of research there is overwhelming scientific consensus (a) that the world is growing warmer, (b) that the accelerating conversion of fossil fuels into carbon dioxide is a major cause, and (c) that enormous changes in the earth's energy balance, hydrologic cycles, climate, and ecosystem function must result.
So as part of my contribution to saving the Solomon Islands from General Motors, I present here a guide to a few of the subtler manifestations of this famous but insidious rhetorical trick:
- Focus on countervailing factors. Climate change predictions aren't easy. While some processes will act change the climate, these will trigger some processes that countervail against their effects. Here is Crumb Trail's Back40, usually a very careful thinker about environmental management issues:
We know so little. We don't understand the carbon cycle, we don't even know which factors are significant. Carbon is a tiny, tiny fraction of the atmosphere yet it is in extremely high demand by every living thing. Life on earth is made of carbon. We are just beginning to understand how the low concentration of atmospheric carbon inhibits life.By pointing out that carbon dioxide enrichment serves to enhance photosynthesis, Back40 is bringing up an important countervailing factor. But it's a countervailing factor that has been part of the climate-change calculations since the very beginning. Working out whether increased primary productivity would just absorb the carbon dioxide being added to the atmosphere has been a major scientific activity for many years. In fact, the increased transpiration which results from the increased plnt growth partly drives some of the forecasted changes in regional precipitation. Back40 explains in breathtaking simplicity the existence of the countervailing forces (he brings up the transpiration issue in the paragraphs that follow the passage I quoted), but he doesn't acknowledge that the complexity he invokes has been grappled with by thousands of scientists spending many millions of federal-grant dollars and has been built into the existing scientific consenses.
- Confuse by conflating. Another interesting thing from that passage (and, more benign because of clumsiness, in this statement by an auto-industry lobbyist) is to shift levels of organization -- in this case, to change the subject from the world's climate to the welfare of individual plants. When Back40 writes life, he means plants but invokes bigger notions, like human welfare. Life has at least a couple of general senses: livingness (i.e, growth, metabolism, cellular organization, etc.), and the experience of being human from birth to death, as in, "What do I want to do with my life?" When two meanings share a word, it allows for confusing arguments -- after all, how can what's good for life be bad for Life?
(Just so you don't think that Back40 is at all like the guy I quote next, I point you to this.)
- Play up complexity by denying it. Lorne Gunter at TechCentralStation writes this:
It should have been impossible for over a decade now for the main greenhouse scientists and politicians -- such as the U.N.'s Intergovernmental Panel on Climate Change, former U.S. Vice President Al Gore and Canadian Environment Minister David Anderson -- to dismiss the impact the sun has on climate change. Heck, it is impossible for my son to ignore. He recently completed first grade, where he learned that day is usually warmer than night, direct sunlight warmer than shade, and summer warmer than winter, and all thanks to "Mr. Golden Sun."Fancy trick here. Gunter simultaneously derides climate scientists for failing to grasp what his first-grader son understands, while arguing that climate is more complicated than environmentalists and mainstream scientists make it out to be. Gunter takes this shot while describing an article suggesting solar brightening as an additional driver of global warming. The authors of that article still believe that greenhouse warming significantly drives climate change, but Gunter glosses over that. Gunter also seems to have missed out on the thousands of studies on fossil-fuel driving of climate change, choosing instead to focus on the occasional article that makes climate science seem less certain and more lost than it really is.
Wednesday, September 10, 2003
Tuesday, September 09, 2003
Size matters, but so does ploidy
I made a somewhat complicated argument yesterday for why the tracheophytes became the dominant form of plant life. To recap:
- Tracheophytes, because they don't depend on water to reproduce and because they had vasculature, could grow into the air. (Of course, the direction of causation could be backward on the vasculature issue, but still.)
- Growing into the air, the tracheophytes didn't suffer from the negative incentive to grow large imposed by light attenuation in the water column.
- On the other hand, because there is also light attenuation from shade induced by neighboring plants, there was positive incentive for the tracheophytes to be taller, in a sort of "arms race" in competition for light.
- Height is size, and in plants size correlates strongly with fitness.
But here's a question: if a multicellular gametophytic phase of the life cycle brought enough of a fitness advantage for it to succeed so well in the algae (because of iteroparity, tissue specialization, etc.), what is it about the seed plants that makes it disadvantageous?
Thursday, September 04, 2003
By turgor alone
For those of you who aren't up on the scientific literature, you can find the short, official biographical sketch of Kif Kroker here. Remember, he's the one whose body is "supported by a system of fluid-filled bladders."
Here's what Karl Niklas (1997, The Evolutionary Biology of Plants, p. 281) has to say about the likes of Kif:
There are two limitations to hydrostatically supported stems [and space-aliens]. First, their mechanical stability depends on a continuous supply of water. Second, they are composed of a heavy material -- water -- and cannot grow too tall before they bend under their own weight.That's why Kif is so short, and why Zapp Brannigan -- who is an idiot but who (like the tracheophytes) has superior mechanical support -- is his boss instead of the other way around.
Tuesday, September 02, 2003
Thrive without intention
A passage I thought about reading aloud in class yesterday, but it seemed hokey to read anything aloud in a biology class:
Astronomers like to say we are fashioned from stardust--that the elements in us were formed in ancient, long vanished stars and differ not at all from those found in the outer reaches of space. If so, then it is also true that we are made from starlight--that our substance is predicated on the way plants convert the energy of sunlight into chemical energy. Because photosynthesis underwrites most of life on Earth, it is only fitting that this book is about living things that thrive without intention, build without blood or brain, move without muscle, summon without self-awareness, and feed the world without intent. In short, this book is about plants.
But is is also important to know how plants achieved the ability to fashion their living substance from sunlight, how they moved this photosynthetic machinery onto land, painted the continents green, fabricated the animals they untintentionally feed and shelter. This book therefore is also about evolution. The inaugural unicellular forms of life in Earth's ancient oceans could not harvest and use sunlight's energy, yet their multicellular descendants now live on land and grow many times larger than the largest animals that ever lived. Clearly plant life has changed over time, and organic change over time is evolution.
From Karl J. Niklas. 1997. "Introduction," in The Evolutionary Biology of Plants. Univ. of Chicago Press, Chicago.
Sunday, August 31, 2003
That's not a pollutant
From an article on the EPA's decision not to regulate carbon-dioxide emissions:
"Why would you regulate a pollutant that is an inert gas that is vital to plant photosynthesis and that people exhale when they breathe?" said Eron Shosteck, a spokesman for the Alliance of Automobile Manufacturers, a Washington-based car industry lobby. "That's not a pollutant."The Clean Air Act charges the EPA with regulating emissions that harm human welfare, including the climate. EPA general counsel Robert Fabricant just ruled that because there's no proof that CO2 affects the climate, CO2 emissions are beyond the EPA's legal jurisdiction. (NYT article here.)
Shosteck is clearly some sort of chemistry genius to get quoted on such an important policy issue, so I'm almost embarrassed to quibble:
- If CO2 is inert, then how could it be vital to photosynthesis? Inert is a word that carries authority from sounding scientific (especially when used in the phrase inert gas, which some people might know names a real category of gases, just not one that includes CO2). Because the word is misused, that authority is a lie.
- Even if CO2 were technically inert, that would only mean that it doesn't participate in chemical reactions. It could still affect the climate by, say, absorbing energy radiated from the earth.
- Plenty of things are benign or beneficial to some things and harmful to others. Good for plants can be perfectly consistent with bad for humans. (Bad for plants probably does mean bad for humans, though.) THC is vital to anti-herbivore defense in Cannabis sativa -- maybe the Bush administration will be pushing to legalize marijuana next?
- The issue isn't CO2 itself, but change in CO2 concentration. The change is not exhaled or used in photosynthesis. Cyanide is benign in concentrations that appear in almonds -- does that mean it shouldn't be regulated?
- Does Shosteck really think that a compound that is a human waste product couldn't in any way be toxic to humans?
Thursday, August 28, 2003
If only it were just branches
Olive trees: potent symbols to some, economic lifeblood to others. It's the whole Israeli/Palestinian conflict in
Wednesday, August 27, 2003
There's a new study in Nature (and summarized at Science Blog) that claims that over 50% of global photosynthesis happens in the oceans. One statement that was of particular interest to me:
Prochlorococcus that survives in extreme low light conditions has more of the antenna proteins compared with strains that live close to the surface and iron is the limiting nutrient that regulates the organism's ability to harvest light energy.
(Note how useful it is that that is not interchangeable with which: some Prochloroccus live near the surface and some live deeper, but the first clause refers only to the latter.)
My question: is the variation in antenna-protein density due to ecotypes or to phenotypic plasticity? There's a thesis project there somewhere.