31 October 2006
Someone, no doubt, has researched extensively the way in which those pesky Hibernian Celts brought one of the best holidays to America. But I haven’t. So I’ll just say happy (belated, to most of you dear readers) Halloween. Enjoy it, and remember Edward Gorey fondly.
To get your daily dose, pick up a John Bellairs book. They’re fabulous.
Dave at WordMunger has a great post on the accelerating pace of gadget change. It’s short–go read it.
If you have a little more time and a sense of humor about academia, check out the Chronicle article “Is Graduate School a Cult?” Mahalo nui to Zuska for that article and several galvanizing examples (or perhaps manifestoes) of sexism in academia. Zuska kicks ass.
24 October 2006
A word about jargon. I recently attended a public talk given to a general audience by an engineer working in astronomy. The engineer used terms like ‘primordial magnetic field,’ ‘wavefront sensor,’ and ‘absorption bands,’ without blushing. The only thing that distinguished the talk from a conference presentation was the redaction (or, more accurately, reduction) of charts, equations, and acronyms. Audience response fell almost completely bimodally: by the end, people were either snoring or blathering. The only possible defenses against such unabashedly obtuse talk were falling asleep or agreeging that, of course, the emperor’s new clothes were very nice.
Another incident that brought the previous one into sharper focus for me occurred a few days later. Two professors of humanities had learned via their eleven-year-old daughter’s science homework that matter had overflowed the bounds of the traditional three states of solid, liquid, and gas. Added to the map, so they bemusedly understood, was plasma. Exactly how this newcomer fit the common landscape or how it differed from the three of immemorial custom was even less clear than the existence of this modified geography.
These two fiercely curious, well-educated people were blissfully unaware of the developments in physical chemistry, high-energy physics, and astronomy that led to the recognition of this ‘new’ state of matter. And why shouldn’t they be? Plasma doesn’t exist in our immediate environment, unless perhaps it is trapped inside your TV by dimly grasped powerful forces. But the conditions of existence necessary for plasma and those for us are mutually exclusive. And until somebody develops the elusive but apparently ubiquitous Mr. Fusion, we’re unlikely to be in close proximity to plasma in our daily lives.
And yet, the engineer of the first paragraph felt that terms far more complicated than mere plasma could be deployed with impunity towards an audience of unknown education and familiartity with the material. The respective responsibilities of the citizen and the researcher to one side, an honest evaluation of and empathy with our fellow travellers might be beneficial. For each of us to admit, perhaps only to ourselves, that we are not always experts but sometimes novices, does us good. And as for plasma being an abstract and unknown concept, it is massively embodied in one very vital place we encounter every day—the Sun.
24 October 2006
As befits an earthquake whose aftermath was less than the 24-hour news channels made it out to be, this post will be less than initially promised. First of all, though, the HVO Current Eqs Map is up and running, though it is a little slow due to heavy traffic. Also, they have the seismograph readings from the Hualalai instrument station (closest to the quake).
I noticed that many media figures, including Hawai`i County Civil Defense officials, referred repeatedly to the magnitude of the quake on the Richter scale. While Richter’s 1935 system (based upon the much-abused scale for measuring star brightnesses, also called magnitudes; that’s a completely different rant) was designed for a specific purpose, it worked pretty well and had a catchy name, so it got pressed into greater service. Also, he was at CalTech when he developed it, and therefore had a lot of reputation to throw around. The Richter scale measures the amount of energy released during an earthquake, and was originally designed for use with a specific instrument at a specific location, but later rejigged for use pretty much wherever you wanted.
A less specific scale of similar utility, a sort of metric system of magnitude if you will, called moment magnitude, was developed in 1979. This new scale was designed to agree closely with the Richter scale, and it is logarithmic in the same way. In both scales, two earthquakes with an increase of one magnitude (4 to 5, say) means the amplitude of shaking is ten times as great at the same distance from both quakes. Likewise, a quake of 5 releases about 32 times as much energy compared with a quake of 4 on both the Richter and moment magnitude scales. Thus, the differences between the scales are pretty much mathematical (as shown here) but as a non-representative sample, I know more seismologists who use moment magnitude than Richter magnitude. These same seismologists do confess that they often use Richter when dealing with the lay public or media, however, because it is much better known. If you really want to get tricky, you can look at centroid moment tensors, which look cool on maps. Unfortunately, the Hawai`i one isn’t big enough to show up on the map they have on the web, but here is the raw centroid moment tensor stuff, for the truly geeked-out. So, use whichever scale you like, unless of course you’re talking about deep earthquakes, in which case, the body wave is a better measurement. Figure it out yourself. Here’s a pretty good description of the various kinds of scales for measuring the amount of energy released, courtesy of the HVO again.
My second point in all of this is that I can’t figure out why hypocenter never caught on the way epicenter has. Google ‘political epicenter,’ and you get over a million hits. Try it for ‘political hypocenter,’ and you get one percent of that. People often use epicenter when they actually mean ‘right where the dang thing happened,’ though. To clarify (and anyone who knows more Greek than I should feel free to display that at this time) the hypocenter is the point way down deep in the Earth where the rupture actually happens (cf hypodermic needle). The epicenter is the point on the surface of the Earth directly above that point (cf epidermis). For the topologically challenged, if you drew a line from the center of the Earth to the hypocenter and kept going until you start blinking really hard, you’d be at the epicenter. That spot doesn’t necessarily feel the greatest effects of the quake, or suffer the greatest damage, either. Those can vary greatly depending on the kind of soil or rock in the immediate neighborhood. Cracks, sinkholes, building collapses and so on do not reliably indicate the epicenter, and are almost never indicative of the hypocenter. Common depths for earthquakes are either 5-10km or about 30km, depending on location and type. All of which is to say that there can be a big difference between hypocenter and epicenter, and the word we use less usually designates the more important point, seismically.
All of this is by way of saying that scientific terms certainly get appropriated, and not always in the way they were intended. Without getting all literal and inflexible and stuff, these two examples might be a case where some clarification from the science-types would be useful in the fray of general discourse.
P.S. Hypocenter apparently is also used to designate the spot right underneath a nuclear bomb detonated in the air. An even less fun place to be than the previous definition.
16 October 2006
At about 7:10 yesterday morning, we felt a pretty good earthquake at our house. Living, as we do, on an active volcano and about five miles as the `alala flies from Pu`u O`o (the active vent on Kilauea), this isn’t that wierd. Except that I was standing outside in the road and I felt it pretty strongly, watching trees swaying back and forth. Our house is built with post-and-pier construction, common out here because the lots are frequently not all that level. It provides the added bonus, however, of doing the same thing the Japanese now spend millions designing their office buildings to do: shimmy so they don’t break. Elle reports that from her observations inside the house (under a doorway—don’t try to run outside, kids) she expected to hear dishes breaking as they cascaded to the floor, but in fact the shelves moved with the house. Our sum total damage was one box of cookies that fell off its shelf. The aftershock about ten minutes later was slightly less strong and definitely shorter–ten seconds, compared with nearly a minute for the first quake. A third felt aftershock at about 10:30a.m. was barely worth mentioning. Elle didn’t even wake up from her nap.
With all radio stations knocked out, our most expedient mode of getting information was to drive the firehouse in Volcano. Noni, the font of all wisdom, had already hear that it was relatively big (prelim 6.5 magnitude, see below) and centered near Pu`uanahulu, on the west side of the island. Subsequent reports would place the quake center offshore, but County Civil Defense did an excellent job of getting the word out that there was no forecast tsunami.
As it happened, not only was the quake not centered near us, our region of the island suffered the least damage. Waiakoloa Village was the closest place with a post office to the epicenter, and they got rocked pretty hard, although no reports of structural damage. But as of yesterday about noon, pretty much every road on the North side of the island was closed. Saddle road remained open, and the entire Ka`u district fared well, save for some rocks on the road in Ocean View. But if you’ve ever been to Ocean View, it would only be news if there weren’t rock on the road. Hamakua coast highway, Kawaihae, Hawi Mountain Road, and both the upper and lower roads from Waimea to Kona remain closed in various places. The Volcano Fire Department stayed true to ourselves (motto: Always Ready, Rarely Paged) but in fact, the Hawai`i Fire Department reported no calls for assistance received due to the earthquake.
The confusion over what roads were closed seems to have been the biggest impact yesterday. The Kona hospital was initially evacuated, but then reopened. A bunch of schools are closed today, and lots of buildings are being evaluated. Some places lost water or power yesterday, but many are back online. In short, no big deal.
Unfortunately, the Hawai`i Volcano Observatory ‘Current Eqs Map’ is down from excessive traffic, but if you want a map, the IRIS seisic monitor is very good. Hawaii Tribune Herald webpage has some photos, but registration is required beyond the ‘front page.’ Also check out the Center for the Study of Active Volcanos page on natural hazards in Hawai`i, which has some excellent preparedness information.
The promised (and truly forthcoming, but maybe not until tomorrow) post will contain information on the not-so-critical difference between ‘center,’ and ‘epi-center,’ and the slightly more important one between the Richter Scale magnitude and the moment magnitude.
So, with roads closed and various utilities crippled, what did we do? Settled in for a beautiful afternoon at home–the wind was blowing (oddly) out of the South, but skies were clear and temperature was right around 70. In fact, we dragged out our hand-crank pasta maker and made a batch of fresh fettucine. I’ll let you know how it tastes.
13 October 2006
Well, I was working only on absence of evidence about the North Korea thing on Sunday. Although many nonproliferation agencies condemned the test, nobody actually said what it was.
Now that I have discovered Jeffery Lewis, I can sleep (more) soundly at night. The money quote from that post:
No one has ever dudded their first test of a simple fission device. North Korean nuclear scientists are now officially the worst ever.
And from the one that I linked to, above.
I close this discourse about operational confidence by noting that the United States has built a missile defense that does not work, to defend against a North Korean missile that does not work, that would carry a nuclear warhead that does not work.
This is all very postmodern.
I love it. Dr. Strangelove, eat your heart out.
Now, back to fearing.
11 October 2006
We spent several hours last night with the current titleholder of the Cutest Child in the World, Camila. Lola was keeping Ramon from going even more crazy while working on his tenure dossier, and we were trusted with keeping the benevolent dictator happy in the meantime.
Despite my complete lack of rational thought during that time, it makes sense this morning to connect with an information design anecdote. While at Gemini, I am surrounded by a lot of technically competend (not to say obsessed) people. This story about Edward Tufte (full disclosure–one of my heroes) fits rather nicely with the theme of the Squirt and the Code.
Dr Spock’s Baby Care is a best-selling owner’s manual for the most complicated ‘product’ imaginable — and it only has two levels of headings. You people have 8 levels of hierarchy and I haven’t even stopped counting yet.