DST in west Amazonas and Fernando de Noronha

Paul Eggert eggert at twinsun.com
Mon Dec 4 23:41:30 UTC 2000

> Date: Fri, 03 Nov 2000 19:17:14 -0600
> From: <jnorgard at Prodigy.Net.mx>

> http://pcdsh01.on.br/Fusbr.htm
> http://pcdsh01.on.br/Fusbrhv.htm

Thanks for those pointers; I'll put them somewhere in my next proposed

> Since the TZ database for Brazil has been elaborated per state, we
> have an obligation to document the exceptions from that.

Yes, I think we should add a new entry, since as far as I can see,
west Amazonas observed DST in 1993/1994, whereas Acre did not; so it's
not the case that the two regions' clocks have been the same since 1970.

> Therefore I suggest to put a second entry in the TZ database for
> Amazonas as "America/Atalaia_do_Norte" or something like that.

The above-listed web page mentions Atalaia do Norte, Boca do Maoco,
Benjamin Constant, Eirunepé, Envira, and Ipixuna as being in west
Amazonas.  I don't know offhand whether these are cities or districts.
I can't access the Brazilian Census Bureau pages at
<http://www.ibge.gov.br/ibge/default.php> (my Netscape 4.76 Solaris
browser rejects it with javascript errors), but
<http://www.dcc.ufrj.br/~cristina/dadosam.html> gives the following
cities in Amazonas, in decreasing order of population:

 MANAUS                       1157357
 PARINTINS                      71574
 MANACAPURU                     65577
 ITACOATIARA                    64937
 TEFE                           62616
 COARI                          53327
 MANICORE                       37704
 MAUES                          36628
 TABATINGA                      32009
 LABREA                         27517
 IRANDUBA                       26612
 EIRUNEPE                       25776
 BENJAMIN CONSTANT              23633
 ENVIRA                         18192
 IPIXUNA                        11120
 ATALAIA DO NORTE               8108

So it appears that America/Eirunepe would be a better choice than
Atalaia do Norte.  However, I don't see a population entry for Boca do
Maoco, and I'm not sure what that is (perhaps a district?).

> According to these official pages, Fernando do Noronha has been on
> DST for some while back (e.g. before October 15 where the status
> probably changed).

I don't read the pages that way.  http://pcdsh01.on.br/Fusbr.htm and
http://pcdsh01.on.br/Fusbrhv.htm both list Fernando de Noronha as
being 2 hours behind UTC.  It is a little tricky, since the pages also
list the offset from Brasilia, and this offset does differ between
winter and summer.

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