[tz] Timezone abbreviations

[Carl Zulauf]

Alain Petit <alain.petit <at> oracle.com> writes:

> 
> 
> 
> [As I was using an incorrect email, I am resending. 
> Apologies if duplicates were issued]
>  
> Hi
> 
>  
> I am looking at 
> the following timezone definition
> 
>  
> # Zone  
> NAME            
> GMTOFF  RULES   FORMAT  [UNTIL]
> Zone 
> America/Metlakatla  15:13:42 -     
> LMT     1867 Oct 
> 18                         
> -8:46:18 -     LMT     1900 Aug 20 
> 12:00                         
> -8:00  -       PST     
> 1942                         
> -8:00  US      P%sT    
> 1946                         
> -8:00  -       PST     
> 1969                         
> -8:00  US      P%sT    1983 Oct 30 
> 2:00                         
> -8:00  US      MeST
> 
>  
> I am trying to 
> make sense of the MeST [the format].
> 
>  
> I think PST means 
> "Pacific Standard Time", and P%sT becomes PST or PDT according to the US rule 
in 
> effect [and making it Pacific Standard Time or Pacific Daylight 
> Time].
> 
>  
> However I cannot 
> figure out what MeST would be, apart from Metlakatla Standard Time 
> ?
> [I found MEST - 
> Middle European Standard Time, but Metlakatla is not in 
> Europe]
> 
>  
> Searching for 
> Metlakatla [google] always refers it as AKST [Alaska Standard Time]. 
> 
> 
>  
> So 2 questions 
> 
> a) What would MeST 
> mean? [and why no '%s' for it?]
> 
>  
> b) Where can I 
> find the meaning of these abbreviations [as I will probably find others that 
> will confuse me in the future]
> 
>  
> 
>  
> Thanks 
> 
> -Alain
> 

I ended up researching pretty much the same question after a timezone library I 
use returned "MeST" for America/Metlakatla. I went to the tz database source, 
obtained from http://www.iana.org/time-zones . The data files are peppered with 
notes that provide discussion and context to many of the timezone oddities.

Short answer: MeST is Metlakatla Standard Time. No %s because the Metlakata 
Indian Reservation does not observer daylight savings time.

Long answer: Here are are the relevant background notes from the 'northamerica' 
file in tzdata2011n.tar.gz.

# From Arthur David Olson (2011-02-09):
# I just spoke by phone with a staff member at the Metlakatla Indian
# Community office (using contact information available at
# <a href="http://www.commerce.state.ak.us/dca/commdb/CIS.cfm?
Comm_Boro_name=Metlakatla">
# http://www.commerce.state.ak.us/dca/commdb/CIS.cfm?Comm_Boro_name=Metlakatla
# </a>).
# It's shortly after 1:00 here on the east coast of the United States;
# the staffer said it was shortly after 10:00 there. When I asked whether
# that meant they were on Pacific time, they said no--they were on their
# own time. I asked about daylight saving; they said it wasn't used. I
# did not inquire about practices in the past.

# From Arthur David Olson (2011-08-17):
# For lack of better information, assume that Metlakatla's
# abandonment of use of daylight saving resulted from the 1983 vote.