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Re: The Sinking of AGW

Germany is not particularly rigorous about SI units. Gasoline is sold in litres for example, beer in millilitres (usually multiples of 100 thereof), it is not uncommon to hear folk requesting loose-sold goods in pounds (though one suspects these are rounded to 500g), rulers have centimetres on them, and so on and so forth. It would be more accurate to say Germany is rigorous about the use of metric units.

Re: Re: The Sinking of AGW

I fail to see the importance of what system is used, cgs, MKS or the "British system", as long as people know how much they are getting for their money. I was exposed to all of these quite widely when I was in college, lo those many years ago, and it seemed to me that they all worked equally well, if you got the terms right.

I once was a professional mechanic, though, before I went into the civil engineering field, and bacame a Professional Civil Engineer, and I can tell you right now, that 0.001 inch differentials is a really handy way to measure clearances. All in essentially "whole" numbers, that is, 0.003 inches clearance for connecting rod bearings, 0.028 inches for spark plug electrode clearance, and the like. Not at all like the trouble it is to have those long decimal parts of millimeters. I will take a feeler gage in 1/1000 of an inch any day.

Re: The Sinking of AGW

Larry, you 'hit the nail on the head':-

“I fail to see the importance of what system is used, cgs, MKS or the "British system", as long as people know how much they are getting for their money.”

I totally agree with you, however, the main point of my 'numbers' post was that we cannot know what we are 'getting for our money' if parties arbitrarily muck about with units of measure without proper definition. (Something which AGW, Politicos, and Epidemiologists are a 'dab hand at').

I too received my education in the 50's, and my abiding memory of those times was the absolute rigour which our teachers drummed into us in the use of numbers, particularly engineering and physics. One aspect of the ethos of my grammar school concerned our ability to Communicate with precision and concision. In composing our written work, we needed no encouragement to do this as it was all long-hand pen and ink: anything which reduced that labour was good, and scientific notation served us well; it also gave us brevity, neatness, and precision. --- (I too, still think in imperial measure for precise engineering work, mainly because my Dad taught me how to select a 2 thou' feeler gauge by sight and feel at the age of 5 or 6: very useful when the etched numbers become worn, and when working in low light conditions.)

JamesV, you could benefit from a proper education, (difficult for your generation, I know). The SI system grew out of the 'metric' system as a collaboration between France and Germany, again, I quote for your edification:- “Legal units are --- the SI units --- decimal multiples and sub multiples of the SI units --- other legal units: see the tables: Selected Quantities and Units (From DIN 1301)”:--- Length l, SI unit = m (metre), mm (millimetre) = sub multiple. Volume V, SI unit = m^3 (cubic metre), l (litre) = sub multiple. Area A, SI unit = m^2 (square metre), ha (hectare) = 10^4 m^2 = multiple, etc. etc.. --- So James, from your post, you unwittingly confirm that the Germans Are Rigorous in the use of the SI system. (And unlike Larry, you hit your thumb instead).

And for Jerry from Dave Gardner's post “Possible August number of the month”, you made a comment about my my response re Oxygen tolerance):-
“There is a nasty habit developing in some (allegedly) technical writing of using "±" to mean "approximately"---”
As here, we are on the subject of correct numerical notation, I would, with respect, bring to your attention some salient facts about the expression of tolerances in technical/engineering notation. First, as a guide to its importance, I quote:--
“The purpose of the ISO system of tolerances is to allow the production of interchangeable parts with the minimum number of tools, fixtures and gauges.”
Long before ISO came on the scene, and well before the industrial revolution, the practical world, in every field, found it necessary to establish 'limits' to numerical values of measure otherwise nothing could work. --- The universal need for tolerances has led to three classical forms of notation used throughout the world, they are:- + / - (plus or minus) + /+ (plus plus) -/- (minus minus) --- Average is the term usually used to denote a value without expressed tolerances. --- So Jerry it is quite correct to state that our bio-chemistry has evolved to function optimally at an Average Oxygen level of 21%, however, in a technical discussion about Oxygen depletion, it is essential that we state the known average tolerance level as well. In the discussion we had, in retrospect, I would put the average tolerance levels for most human beings at, +/- plus 10% and/or minus 15%. But our tolerance level to, say, changes in our core body temperature could well be, for hyperthermia, +/+ plus 10% to plus 15%, or for hypothermia, -/- minus 10% to minus 15%.

Useful things tolerances, when properly used. My system's tolerance to AGW hype is , -/--------------------------------------

David

Re: Re: The Sinking of AGW

David,
I couldn't agree more. That was precisely (!) the point I was making. Did you wish to indicate that the levels of Oxygen were between 17.9% and 23.1% you would be quite correct to express it as 21% ± 10%, but in far too many cases what we see is "Oxygen levels are ±21%", i.e. "±" is used to mean "about". As you have so clearly shown this leads to confusion.
BTW, I'd get your tin hat on fast before JamesV gets back!

Re: The Sinking of AGW

I would suggest we consider that we live in what Scot Adams (creator of Dilbert) refers to as a "Confusopoly".
The objective of systems such as SI is to make things simple by the application of a common standard. Indeed, a principle which is the alleged foundation the whole concept of the European union; but which conceals a different reality.

With the collapse of the western economy (sorry for the tabloid speak) we had no immediately obvious drop in price in many of the ggods on our supermarket shelves; until it was explained that as part of "helping the shopper" to continue to meet their bills, manufacturers were reducing the contents of many products on sale. Sure the contents "may have settled in transit" but they were also reduced while the money charged remained the same.
This is simple misdirection.

The concept of a confusopoly is that market forces are neutralised.
Ostensibly we avoid allowing any one company to have a monopoly on the market. Thus we do not have one mobile phone service provider, we have many. In a rational market place the conventional wisdom is that by having competing companies we will get the best price.
In Scot Adams' confusopoly world no two companies offer exactly equivalent products. This makes it exceedingly difficult to select between on the basis of price and as a consequence, the effect of competition which we expect to reult in lower prices does not appear to have any impact on prices at all.

Now we come to standards and SI units.
It is a sobering thought that standards are set by committees and you will at once recognise the flaw.
No committee, having debated at length and finally produced its new standard to an expectant world likes to see its existence ended.
Committee work is, to quote Arfer Daily, "a nice little earner".
So no committee likes to return after a break of a year or two to say "no, we don't need to met ever again, we got it al right the first time round."
They can always think of new things to do.
Take temperature, for example (and I choose this example because we are much vexed by the question of global temperatures).

We might well remember that the UK used to use degrees Fahrenheit or, at a push, degrees Rankin.
When I was at school the alternatives were degrees Centigrade and degrees Kelvin.

You might well think that there isn't too much that a committee can do to make money out of such a basic measurement, apart, of course, from changing the names every so often such as changing Centigrade to Celcius.
Such too was my view until i stumbled into some work reappraising some spreadsheet calculations.
It appears that committees (are they hereditary positions one wonders?)met in 1927, in 1940, in 1968 and again in 1990 to tinker with the temperature scale.
It appears we have an International Temperature scale.
t68 is the degrees in Celcius under the ITS 68 temperature scale, T68 is the degrees kelvin. In 1990 a new temperature scale was introduced where t90 and T90 are the degrees Celcius and Kelvin on the ITS 90 scale.

It appears that a degree Celcius on the ITS 60 standard is not the same as a degree Celcius on the ITS 90 scale. The differences are not major but surfice it to say that if you measured some important parameter at 20degrees C in the 1960s and wanted to reproduce that measurement in the 1990s you would get a different value for your parameter.

So temperature sensors would today be calibrated to the ITS 90 scale.

Of course, when trying to make some sort of sense of a whole lot of data collected over a long period of time, extending back across a century, say, one would have to be sure to compensate the data sets to accommodate the the different temperature standards.

Of course, the errors are only significant under some circumstances.... but I wonder if we should inquire if the corrections have be resolved in the preparation of the latest "hockey stick" revivalist effort? This is another opportunity to further manipulate the data...

Re: The Sinking of AGW

JamesV, you could benefit from a proper education, (difficult for your generation, I know). The SI system grew out of the 'metric' system as a collaboration between France and Germany, again, I quote for your edification:- “Legal units are --- the SI units --- decimal multiples and sub multiples of the SI units --- other legal units: see the tables: Selected Quantities and Units (From DIN 1301)”:--- Length l, SI unit = m (metre), mm (millimetre) = sub multiple. Volume V, SI unit = m^3 (cubic metre), l (litre) = sub multiple. Area A, SI unit = m^2 (square metre), ha (hectare) = 10^4 m^2 = multiple, etc. etc.. --- So James, from your post, you unwittingly confirm that the Germans Are Rigorous in the use of the SI system. (And unlike Larry, you hit your thumb instead).
====

Exactly. Can you please tell me why, if the Germans are so rigorous about SI units, my local petrol station charges me for litres of gasoline rather than cubic metres (or rather cubic decimetres)? I know it might seem like a trivial point, but the litre is not, never has been, and never will be (if future committees have any sanse) an SI unit. The law is wrong in implying it is. It is a subdivision of convenience of a derived SI unit, and one for which a common exception is made because it is such a useful, everyday quantity. It does, however, demonstrate that the Germans are not "rigorous" about using SI units but quite prepared to make exceptions of convenience where this is helpful in everyday life. It is just easier, especially for poorly-educated people like myself, to think of 25.76 litres of gasoline than 0.02576 m^3 of gasoline. The risk of an order of magnitude error is reduced considerably by using numbers greater than 1, which is also why, in the lab, we use even smaller subdivisions, microlitre subdivisions on the pipettes and such, whereas under pure SI we should be talking about intervals of 0.000000001 m^3. But today's poorly-educated scientists don't like such inconvenient numbers very much - I suppose that's human psychology and bad education for you.

I'd also be very interested to know why "Are" and "Rigorous" are deserving of capital letters - after all, I need to improve my English, don't I?

Re: The Sinking of AGW

But our tolerance level to, say, changes in our core body temperature could well be, for hyperthermia, +/+ plus 10% to plus 15%, or for hypothermia, -/- minus 10% to minus 15%
====

And I'm the one in need of an education?

Textbook human core temperature is 310K. A 10% increase gives 341K. A human at 310K is a dead human.

Of course, we should be using the Kelvin scale (or any absolute scale), unless of course you think that 100°C is twice as hot as 50°C (which raises the interesting question "is 0°C twice as hot as 0°C and 1°C infinitely hotter than 0°C")

Re: The Sinking of AGW

That should read "a human at 341K is a dead human".

Re: The Sinking of AGW

I don't think I have ever come across the use of "million" or "billion" in any scientific documentation I have read or written. I suspect they do come up in discussion of the ever-problematic units of volume, where there could be semi-legitimate discussion of millions or billions of cubic metres where the correct way of dealing with the problem is to talk about cubic kilometres. Only a cubic kilometre implies 1000 cubic metres to the uninformed, out by six orders of magnitude, and is thus capable of causing confusion to the scientifically illiterate.

"Billion" in Germany is now in common use as 10^9, but only in English. In German "Milliard" is 10^9, and "Billion" simply never comes up that I am aware of, but you are more likely to hear these in a business discussion than a scientific one.

Anyone using "billion" "trillion" etc. here had better be aware of the ambiguity and be prepared for their bid for some company or other to cost them 1000 times what they were hoping to pay.