On Mon, 07 Jul 2003 11:05:54 GMT, "Bob Harrington"
wrote:



"Gene Nygaard" wrote in message

On Sat, 05 Jul 2003 22:03:29 -0500, David Ball
wrote:

On Sun, 06 Jul 2003 01:43:15 GMT, Gene Nygaard

wrote:

On Sat, 05 Jul 2003 20:11:42 -0500, David Ball
wrote:
snip
Actually, there is a hectopascal. What you are objecting to is
its use as common jargon. The goal of such jargon is to
facilitate communication. If you know that it is equivalent to
millibars, what are you complaining about? Meteorologists will
continue to use
millibars because it is convenient to do so. If it ain't
broke, don't fix it.

It is broke. That's the only reason hectopascals exist in the
first place, is the pressure to get rid of those obsolete
millibars.
snip
Millibars are bad, a unit which has outlived its usefulness.
Hectopascals are worse, wrong from the beginning. But even worse
than that are the millimeters of mercury used for blood pressure by
doctors in Canada and the United States. Of course, the inches of
mercury
used in meteorology in the United States are a couple more steps
below that.

A very important part of SI is that it is an interdisciplinary as
well as an International System of Units. There is absolutely no
reason
whatsoever why we should have to learn a whole new set of
measurement units, just to learn about and discuss some field of
activity we
haven't been involved in before. There's no reason why scientists
involved in interdisciplinary activities should have to make
conversions one way for one tribe of scientists, and the other way
for a different tribe, just to work together.

But above you mentioned the importance of communicating with the
public - why would you then force hundreds of millions of people to
learn a new system when the old one has served them perfectly well for
decades?

I guess you were sleeping when David Ball told us that the Canadian
public has made the change quite easily, and that he does use the
proper SI units when communicating with them--it is just the
meteorologists who have difficulty getting it right.

Conversions aren't all that hard for folks, especially scientists
(recent NASA Mars probe snafus notwithstanding), if nothing else, it
keeps the brain keen. This clamoring for change simply because it is
the current True Way of those who think they know better than the rest
of us is little more than...

Conversions are a pain in the ass, and most people don't bother making
them--for one thing, they don't know the conversion factors. They
waste time when they need to be done. Furthermore, any time you
convert between units (at least those not related by exact powers of
ten), you lose something. The most common losses are either some of
the precision of the original measurement, or the sense of how precise
it actually is. Most importantly, the need to make conversions is an
unnessary opportunity for error. Not only errors in the calculations
and the transcription of the numbers, but as that Mars Climate Orbiter
example shows, one common error is a failure to recognize that a
conversion is even necessary.

Gene Nygaard
http://ourworld.compuserve.com/homepages/Gene_Nygaard/

(I R A Darth Aggie) wrote in message ...
On Sun, 06 Jul 2003 21:11:37 GMT,
R. Martin , in
wrote:

+ Of course, you'll continue to argue about this for a while because
+ that is the way these "units" arguments, which I think are as old
+ as Usenet, always go. Eventually people get tired and decide there
+ are other topics of interest, at least until someone else decides
+ to raise the tired topic again.

No, no, it isn't a case of "raise the tired topic" so much as trolling
with it...

James

I stand corrected.

Regards,
Russell

On Mon, 07 Jul 2003 07:23:38 GMT, Gene Nygaard
wrote:

On Sun, 06 Jul 2003 20:06:36 -0500, David Ball
wrote:

On Sun, 06 Jul 2003 14:05:47 GMT, Gene Nygaard
wrote:


It is broke. That's the only reason hectopascals exist in the first
place, is the pressure to get rid of those obsolete millibars.

LOL. Who says millibars are obsolete?

CGPM. ISO. NPL. NIST. Measurement Canada. WMO. Many more.

Hmmm...did you check with the meteorologists? You know, the
people who use the units?

That's what the WMO I referred to is. They have recognized the need
to get rid of millibars; they just haven't been smart enough to to it
right. A branch of Environment Canada is also the meteorological
organization using kilopascals.

No. Those are bureaucrats. I'm talking about the people who
actually do the work.


Feel free to jump in with any standards from any international or
national or professional meteorological organization advocating the
use of the millibar. Prove to us your claim that there is nothing
wrong with millibars. But also let us know the ones you run across
that indicate there is indeed something wrong with the continued use
of millibars.

LOL. Feel free to jump in any time you want to make sense. I
don't have to prove anything.



Hmmm...so scientists should only use words that can be
understood by the public? That's an interesting idea.

No. It's more like you should be using the same units real scientists
use. And so should the general public, many of whom are involved in
some field of science anyway.

I do. They're called millibars. I can go into a room full of
meteorologists anywhere in the world and use those units and people
will know what I'm talking about, and that, after all, is the goal:
communication.



Technically, millibars are SI. They're called hectopascals.

No, millibars are not SI, and never will be. One of the hallmark
qualities of the SI is that it is a "coherent" system of units. Bars
are not coherent with this system. The coherent derived units are
some unitary combination of the base units in that system; the bar is
100000 times the combination of base units in SI.

No, the pound is not coherent. Neither is the mile. The beauty
of SI is that is uses multiples of 10. Other units do not. Are you
suggesting that all aviation forecasters stop using knots? Should we
write marine forecasts in m/s just to keep you happy, or do the users
have some say in the matter as well? Like I said, you've got way too
much time on your hands if this is such an irritant for you.



There is absolutely no reason
whatsoever why we should have to learn a whole new set of measurement
units, just to learn about and discuss some field of activity we
haven't been involved in before. There's no reason why scientists
involved in interdisciplinary activities should have to make
conversions one way for one tribe of scientists, and the other way for
a different tribe, just to work together.

So what you're saying is that we need to dumb down the
science....

How in the world can using the same units of measurement as the
scientist themselves use, when you are working with them, involve any
"dumbing down" of the science?

You're saying that working scientists, and that is what
meteorologists are, can only communicate among themselves in a manner
that is acceptable to you. Sorry, but the goal of communication is the
effective exchange of information. While there is certainly some truth
that using common units to exchange information with the public
facilitates such information exchange, there is absolutely no reason
that in discussions with my colleagues that I use the same convention.



It isn't simply a matter of what meteorologists want to use.

I'm afraid it is. I and my collegues communicate using them.
Do we use them when speaking to the public. No. We use kilopascals,
but for internal communications, what we use is entirely up to us.
Now, had you started this thread with a plea that meteorologists use
standard conventions when speaking to the public, I would happily
agree with you, but you didn't say that. Did you?

Like you, I took this thread as I found it. But if I had started this
thread, I certainly wouldn't have said anything like that. That's a
bunch of hogwash.

Well, you are entitled to your opinion, but at the end of the
day, what you and I think really doesn't matter.

On Mon, 07 Jul 2003 08:45:35 -0500, David Ball
wrote:

On Mon, 07 Jul 2003 07:23:38 GMT, Gene Nygaard
wrote:

On Sun, 06 Jul 2003 20:06:36 -0500, David Ball
wrote:

On Sun, 06 Jul 2003 14:05:47 GMT, Gene Nygaard
wrote:


It is broke. That's the only reason hectopascals exist in the first
place, is the pressure to get rid of those obsolete millibars.

LOL. Who says millibars are obsolete?

CGPM. ISO. NPL. NIST. Measurement Canada. WMO. Many more.

Hmmm...did you check with the meteorologists? You know, the
people who use the units?

That's what the WMO I referred to is. They have recognized the need
to get rid of millibars; they just haven't been smart enough to to it
right. A branch of Environment Canada is also the meteorological
organization using kilopascals.

No. Those are bureaucrats. I'm talking about the people who
actually do the work.


Feel free to jump in with any standards from any international or
national or professional meteorological organization advocating the
use of the millibar. Prove to us your claim that there is nothing
wrong with millibars. But also let us know the ones you run across
that indicate there is indeed something wrong with the continued use
of millibars.

LOL. Feel free to jump in any time you want to make sense. I
don't have to prove anything.

No, you won't say any more about this subject, because you know what
the answer is. Even the meteorological standards organizations know
that there is something wrong with millibars.

Hmmm...so scientists should only use words that can be
understood by the public? That's an interesting idea.

No. It's more like you should be using the same units real scientists
use. And so should the general public, many of whom are involved in
some field of science anyway.

I do. They're called millibars. I can go into a room full of
meteorologists anywhere in the world and use those units and people
will know what I'm talking about, and that, after all, is the goal:
communication.



Technically, millibars are SI. They're called hectopascals.

No, millibars are not SI, and never will be. One of the hallmark
qualities of the SI is that it is a "coherent" system of units. Bars
are not coherent with this system. The coherent derived units are
some unitary combination of the base units in that system; the bar is
100000 times the combination of base units in SI.

No, the pound is not coherent. Neither is the mile. The beauty
of SI is that is uses multiples of 10. Other units do not. Are you
suggesting that all aviation forecasters stop using knots? Should we

Certainly.

Check the METAR standards. The standard calls for wind speeds in
meters per second. Some countries such as the U.S. and Canada do use
knots, but they deviate from the international standards in many other
ways as well. About the only one they follow is the use of degrees
Celsius for temperatures and dew points, something where the U.S. and
Canada used different units in the old SA format (with neither of them
identifying the units used). See more on this at
http://ourworld.compuserve.com/homep...rd/usmetar.htm

Other countries (I don't know which ones) deviate from the standard by
using kilometers per hour for this purpose. We know this because a
unit identifier is specified for this purpose, something that wouldn't
be done if nobody used them.

So yes, indeed, follow the standard and use meters per second, as some
countries do.

Beable van Polasm writes:

(Joseph Michael Bay) writes:

Beable van Polasm writes:

If I ever meet a real live meteorologist, first of all I'm going to
ask her how many meteors she's actually seen, then I'm going to use
wacky units to measure everything. "Yes I was driving my truck along
at 167024.24 furlongs/fortnight, when suddenly a kangaroo jumped out in
front! This kangaroo was at least 216 barleycorns high! So I did the
only safe thing and ran into it. At least I salvaged 750 hectograms of
meat for the dog out of this sad incident".

How many cubits per hogshead does your truck get?

Assuming that you are using 864 shoeiron cubits, about 6638696.4
cubits/hogshead of diesel.

At this point I could use a couple barn megaparsecs of single malt.

--
- Doctroid Doctroid Holmes http://www.richholmes.net/doctroid/

"We're waist deep in the Big Muddy
And the big fool says to push on." -- Pete Seeger

In article , R. Martin wrote:
Gene Nygaard wrote:

IMO David is correct. For ease and clarity of communications,
especially among professionals, the professionals doing the
communicating should, as they always have, choose the units.
It is a convention, perhaps less formal than SI, but a manmade
convention none the less, and nothing is sacred about any of them,
including SI, as long as they do the job.

Many years ago, a colleague gave a seminar discussing a flash flood event.
He mentioned that the rainfall rates from these storms were XX inches/hour,
then backtracked and, with a wink, give them in SI units of meters/sec.
Very useful number in the first form, totally useless in the second. And
the original value could have been given in cm, or mm, or m per hour and
still been usful.

Sometimes SI units get in the way of communicating information.


-db-
--
+------------------+
David Blanchard
+------------------+

On Mon, 7 Jul 2003 20:58:06 +0000 (UTC),
David Blanchard,,, , in
wrote:
+ In article , R. Martin wrote:

+ IMO David is correct. For ease and clarity of communications,
+ especially among professionals, the professionals doing the
+ communicating should, as they always have, choose the units.
+ It is a convention, perhaps less formal than SI, but a manmade
+ convention none the less, and nothing is sacred about any of them,
+ including SI, as long as they do the job.

Agreed.

+ Many years ago, a colleague gave a seminar discussing a flash flood event.
+ He mentioned that the rainfall rates from these storms were XX inches/hour,
+ then backtracked and, with a wink, give them in SI units of
+ meters/sec.

Surely you're joking, Mr. Blanchard!

+ Very useful number in the first form, totally useless in the second.

No doubt. If I did my computations correctly, a 10 inch/hour rain rate
works out to 7x10^-5 m/s. I can hear my college physics instructor
bellowing about significant digits and accuracy even now...

James
--
Consulting Minister for Consultants, DNRC
I can please only one person per day. Today is not your day. Tomorrow
isn't looking good, either.
I am BOFH. Resistance is futile. Your network will be assimilated.

On Mon, 7 Jul 2003 20:58:06 +0000 (UTC), (David
Blanchard,,,) wrote:

In article , R. Martin wrote:
Gene Nygaard wrote:

IMO David is correct. For ease and clarity of communications,
especially among professionals, the professionals doing the
communicating should, as they always have, choose the units.
It is a convention, perhaps less formal than SI, but a manmade
convention none the less, and nothing is sacred about any of them,
including SI, as long as they do the job.

Many years ago, a colleague gave a seminar discussing a flash flood event.
He mentioned that the rainfall rates from these storms were XX inches/hour,
then backtracked and, with a wink, give them in SI units of meters/sec.
Very useful number in the first form, totally useless in the second. And
the original value could have been given in cm, or mm, or m per hour and
still been usful.

Sometimes SI units get in the way of communicating information.

Canada went metric decades ago. I can go into any supermarket
in this country and find produce sold by the pound and the kg. For the
grocer, the goal is the sell the produce. For the customer, it is to
figure out how much X amount of produce is going to cost them. At the
end of the day, that is what is important, not what the unit is.
Standards are laid out, not to be draconian, but to offer precision.
If your KG is different than mine, there is a problem. They should
never be used as a way of restricting communication.

On Mon, 07 Jul 2003 12:15:31 GMT, Gene Nygaard
wrote:



But above you mentioned the importance of communicating with the
public - why would you then force hundreds of millions of people to
learn a new system when the old one has served them perfectly well for
decades?

I guess you were sleeping when David Ball told us that the Canadian
public has made the change quite easily, and that he does use the
proper SI units when communicating with them--it is just the
meteorologists who have difficulty getting it right.

LOL. I never said that, Gene. I said standard units are
provided to the public. Nothing more. I also said that there is
nothing wrong with using standard units internally either. You seem to
have a corncob inserted in a certain orifice about that. Too bad. Deal
with it. The goal is effective communication of ideas between peers.
Anything that satifies that goal is OK with me.

In article ,
Gene Nygaard wrote:

Conversions are a pain in the ass, and most people don't bother making
them--for one thing, they don't know the conversion factors. They
waste time when they need to be done. Furthermore, any time you
convert between units (at least those not related by exact powers of
ten), you lose something.

Not to throw gas on the fire, but what if they're related by exact
powers of two? Or three? Or, heaven forbid, five?

Ricky (wondering)