following NIST rules would make AR5 better

[Jan Hollan <hollan@mail....cz>]

Dear Secretary,

I have noticed that WG I drafts for AR5 suffer the same problem as all 
previous IPCC documents: they ignore some good rules for expressing 
quantities.

In short, there must be a space before %, °C, and between Pg or Gt and C.

It is no trifle, as I reason in length, with apologies to bother you. If 
you know a better person to whom should I address my concern, please fw my 
letter accordingly.


In length, now:

Those rules are explained by NIST, there are serious arguments why they 
should be obeyed. In all documents, but mainly by such, which may 
influence millions of readers for many years.

I have decades of experience that writing quantitative expressions 
carelessly results in misunderstanding; it prevents people getting a 
proper knowledge of the issue.

Fortunately, there are not many kinds of such sloppy quantitative 
expressions in IPCC reports. They are easy to correct by a script (in html 
versions) or by an editor, just replacing several types of strings. No 
need to discuss it with authors or reviewers. Writing standards are 
nothing to struggle with.

A shortest possible introduction into proper writing of units etc. is

  http://physics.nist.gov/Pubs/SP811/sec11.html

 - a checklist for editors.


So, several things to be corrected in AR5:


1) there is to be a space between a number and %
 -- see item 10 of the checklist or, in more length,
  http://physics.nist.gov/Pubs/SP811/sec07.html#7.10.2

   (It continues by a paragraph recommending to avoid ppm, ppb and ppt,
 but I think their use is OK for concentrations; they are separated by
 space from the number in AR5 drafts, correctly, it is perhaps obvious
 that the  % sign has to be treated the same way.)

2) the same for degrees Celsius, for more reasoning see
  http://physics.nist.gov/Pubs/SP811/sec07.html#7.2

3) PgC is a nightmare. No symbols of units are to be mixed with another 
stuff, see items 4 and 6 of the checklist, or
  http://physics.nist.gov/Pubs/SP811/sec07.html#7.4 and 7.5


So, please never write PgC or PgCO2. A space must be between the unit and 
a chemical symbol: Pg C, Pg CO2. The gram is always the same thing, there 
are no special grams for different stuffs.

(A similar mistake is "having" watts of electricity and heat, like We and 
Wt - if needed, the "W (e)" or "W (t)" can be written to distinguish 
between work and thermal flux.)

(As for Pg, I'd much prefer Gt, as fuels are sold rather by tons than by 
grams; giga is a much more common prefix than peta -- but of course, using 
petagrams is no mistake, just an obstacle for at least 90 % of readers. 
Kiloton, megaton, gigaton -- all are OK for NIST, unlike militon, and are 
accepted for use with the SI. Rejecting Gt in favour of Pg is, in my 
honest opinion, of no good. I will change Pg to Gt in translations, 
knowing no argument against.)


The whole NIST Special Publication 811 is available, as a single pdf or a 
html tree, at
  http://physics.nist.gov/cuu/Units/bibliography.html
 and is worth while to study, for any authors and editors. Perhaps there 
is another document which may supersede the NIST one, but I don't know 
any. So I adhere to SP 811...


Actually, I mentioned it to some TSU of an IPCC special report already. 
A hint is the end of the English
  http://amper.ped.muni.cz/gw/ipcc_cz/README.html
 at my page with Czech versions of IPCC documents:
  http://amper.ped.muni.cz/gw/ipcc_cz/

I understand that they may be reasons why NIST recommendations are not 
followed by IPCC - but in such a case, a document explaining them should 
exist, and a paragraph on conventions differing from NIST should precede 
any document which does not adhere to NIST fully.


yours sincerely,

 Jenik Hollan, maintainer of a Czech electronic library on Climate Change,
    http://amper.ped.muni.cz/gw/

PS
 Another thing which may be of interest for AR5, is making the glossaries
 hypertext. Like http://amper.ped.muni.cz/gw/ipcc_cz/glossary_i.htm or
 http://amper.ped.muni.cz/gw/ipcc_cz/glossary_i.pdf
 or a bilingual English-Czech ones, html or pdf, like
 http://amper.ped.muni.cz/gw/ipcc_cz/gloss_en_cz.html
 -- it was a bit of programming to create it from the original, but I
 think it was worth while. I hope I have the needed scripts somewhere, so
 that I would be able do the same for AR5.

 And, the glossaries should perhaps explain, what is understood by
 Earth System - like
http://www.igbp.net/globalchange/earthsystemdefinitions.4.d8b4c3c12bf3be638a80001040.html

----------------------------------------------------------------------
                             Jan Hollan, Ph.D.

CzechGlobe - Global Change Research Centre of the Acad. Sci. Czech Rep.

AdMaS - Advanced Materials, Structures and Technologies Centre 
of the Brno University of Technology

			           home:
Lipová 19, 602 00 Brno                         fix. +420 5 43 23 90 96
                            mob. +420 606 073 562

             volunteer of the Ecological Institute Veronica
Panská 9, 602 00 Brno, Czechia                  http://www.veronica.cz

e-mail: hollan@ped....cz              http://amper.ped.muni.cz/jenik
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