Posts by Ross Mason
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He NZlemming. If the water didn't satisfy you, how long was the piece of string?? :-)
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NZlemming........
You are in advertising aren't you. -
Its Friday.
Todays neat bit of science for you all. Ice melts at 0 deg C. A simple statement. If you have a bowl of ice and water, stick a thermometer in it and let it melt, it will sit at 0 deg C until it is all melted. If you then cool it, it will start freezing and then sit at 0 deg C until it is all frozen. That is the simple story. If you then put some really really pure water in a glass tube, evacuate it, suck as much air out of it as possible, you are left with only water and water vapour in the tube. Freeze this and the water is then at it's triple point. So called because all 3 phases of water are in equilibrium. Water vapour, liquid and solid. The temperature of this is now not 0 deg C but +0.01 deg C.There are only two defined points on the thermodynamic temperature scale. Absolute zero and the triple point of water. 0 k and 273.16 k. (k = kelvin, equiv to deg C but with 273.15 subtracted from it.)
If you then stick a really really good thermometer in the tube of water, the triple point can sit there for literally months with a few millionths of a degree. 0.000001 or 2 ish of a degree. Chances are, if we could ensure less electrical noise, vibration and better instrumentation, we could probably show it will sit there within fractions of a microdegree. It is an amazingly small temperature difference and impressive physical phenomenon.
You have to say to yourself sometimes, why does this happen?? What causes this constancy of temperature while a phase change is happening?? We are trying to figure that out along with lookig at how other other metal freezing points that define the usuable temperature scale behave similarly.
What is fun is that I get to play with toys that can measure that good.
It gets better. Hydrogen and oxygen have more than one isotope. The concentration of these different isotopes has a small but measurable effect on the triple point of water. So if I make one of these triple point cells in NZ and one in France say, and we measure the triple point of water, we will find we get two different numbers. Now that really really is annoying. But incredibly interesting at the same time!
Work done here at Measurement Standards Lab over the last 20 years or so has enabled us to make corrections that we can now apply to all our triple point cells around the world so that we can all measure the triple point of water more accurately.
So what? In a bizarre set of steps from such incredible precision, eventually, when you go down to the doctor and he sticks a thermometer into you, the idea is that the temeprature he measures is tracable to the triple point of water. The temperature in Palmerston at 5am this morning also has some measure of reality because the Metservice back track their temperature calibrations to our triple point of water.
Ain't science fun!!!
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A nice series of posters was put out for the IGY.
You will see numbers all over them. I got carried away and photoshopped the whole fracking (heh) lot of them a few years ago and got rid of the numbers.
If anyone wants a "clean set" let me know.
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Alas, poor Ian, me is older than thee. I wintered in 1982. I hope you got more trips than once in that 10 years. The REAL Skidoos arrived literally as we was leaving. I had one zap on them. The previous ones were goats. As slow as and no fun.
Skiddoo out of a crevasse? No. Prussic? Yes. My picture of ID booting it vertically out of a crevasse is hard to eliminate....
Local ingredients??? Hmmm.... the dogs were still down there and we got to 'feast' on seal meat since a few seals were shot for winter dog food. If there was nothing else I could imagine I could get to 'like' it.
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Bryan Walker on Sciblogs has writ a piece that links to a BBC report by Prof Steve Jones on
CBBC Trust review of impartiality and accuracy of the BBC’s coverage of science
"He was asked to assess the impartiality and accuracy of BBC science coverage across television, radio and the internet. "
He (Prof Steve Jones) reports “widespread concern within the scientific community that in News and Current Affairs undue attention is given, when certain subjects are discussed, to oppositional views of received results.”
Bryan ends with this cracker:
On a much humbler level than the BBC I can’t leave the subject without pointing to a recent example in New Zealand’s newsprint media of where the provision of so-called balance can lead an otherwise sensible and serious coverage of a climate change issue. Under the heading Climate change evidence ‘undeniable’ Kiran Chug reported the comments of prominent climatologist Dr Kevin Trenberth, Professor Lionel Carter of Victoria University’s Antarctic Research Centre and Professor Martin Manning, of Victoria’s Climate Change Research Institute. They all pointed in the same direction – that extreme weather events, warming oceans and Antarctic ice melt are signs that global warming is under way and its consequences are global and serious. Then suddenly, in a final brief paragraph, the reader was informed that ACT candidate and agriculture spokesman Don Nicolson sees it all as a matter of natural variations in climate: “No-one can give me conclusive proof that mankind is actually having an effect on the weather.”
What happened? It’s an obvious add-on. Did the writer think, “Gee, I’d better get an opposing opinion in before I finish”? Or did someone up the editorial chain say to her, “You need a balance. Give Don Nicholson a ring”? Either way it’s patently ridiculous and a good local example of exactly the false balance that Professor Jones points to in his BBC report.
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Horns of the di lemma? Horn, horns, horning around.
Lederhausen or as Wiki points out, these are more correctly Liederhosen, song-breeches.
Their socks are down!!!! A bit Ruff.
Heh. Try this armpit muso
or this guyI bet both their names are Stan.
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Heh.
So...Hilary...are we off to the knackers now?
Pssst....call me. I'm good with gizmos.
Nice tree hut though...don't you think?
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As an old Antarctic explorer, may I comment on your "igloo". We were taught how to make both igloo and hedgehog. Yours is technically a hedgehog. What is supposed to happen is the support you piled the snow over gets removed and the inside hole gets 'chiselled' out to fit he who wishes to inhabit the 'obbit hole. We piled snow over our packs. The snow (if it is crispy enough) will stick quite nicely such that you can even stand on it.
How goes your snow??? Is suspect your snow is NZ sea level snow. Wet.
And when the wind stops blowing.....isn't it amazingly quiet??? I remember being in the Windless Bight, south of Ross Island. The quietest place I have ever experienced. Nothing. White, deep snow, miles from anywhere and you could even hear your blood flow. Breathing was too noisy.
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