2002-03-05 I think for practical purposes, they would drop the 0.15 and just call it 273 K. Unless you are a weather spokesman for the BWMA, then you would do it, just to make SI look silly.
John ----- Original Message ----- From: "Duncan Bath" <[EMAIL PROTECTED]> To: "U.S. Metric Association" <[EMAIL PROTECTED]> Sent: Tuesday, 2002-03-05 21:20 Subject: [USMA:18555] Re: Centigrade-Celsius Differences > For everyday use, the celsius scale certainly has an intuitive factor going > for it. > For example, I would not relish weather maps with the isothermal line > separating ice and snow from water and rain labelled 273.15 K > > D. > > -----Original Message----- > From: Ezra Steinberg <[EMAIL PROTECTED]> > To: U.S. Metric Association <[EMAIL PROTECTED]> > Date: March 5, 2002 19:38 > Subject: [USMA:18553] Re: Centigrade-Celsius Differences > > > >Given what Gene wrote, it looks to me like the use of the Celsius scale is > >quite similar to the use of the liter, in that both are defined in terms of > an > >SI unit, are not themselves units, and are kept mostly for reasons of > history > >and convenience than anything else. > > > >Ezra > > > > > >Gene Mechtly wrote: > > > >> What is the difference between the historical definition > >> of the centigrade temperature scale and the modern Celsius scale? > >> > >> In 1742, Anders Celsius published a paper titled (after translation) > >> "Observations on Two Constant Degrees on One Thermometer" in the > >> Transactions of the Swedish Academy of Sciences. > >> > >> The *two constants* were the ice point and the boiling point of water, > >> separated by exactly 100 degrees on that "centigrade" scale. Celsius > >> chose the boiling point as the zero on his original scale. > >> > >> On the other hand, the modern Celsius scale has *only one* fixed point, > >> a zero at 273.15 K, and an increment (unit) of temperature difference > >> identical to 1 K, as Jim Frysinger has explained. > >> > >> Thus, the original "centigrade" scale was, in fact, *different* from the > >> modern Celsius scale. > >> > >> However, the definition of the original centigrade scale, and its > >> immediate successor with the zero reset at the ice point, were > effectively > >> discarded by a series of resolutions by the CGPM as Joe has explained. > >> > >> Gene. > > >
