Chinese timezones

[Jesper Norgaard Welen]

Thanks for this magnificent link. I had already been using
http://www.astro.com as one source for determining latitude/longitude for
cities. But I had no idea that you could actually use it as a timezone
converter, even for historic times, and indeed implements the Shanks &
Pottenger database.

I have been following your advice and wandered around to find possible
boundaries of timezones. In the "Beijing" area I have not found any
deviations, but I have also not pushed it far. So Asia/Shanghai seems to
cover the regions Hebei, Shandong, Fujian, Jingxi, Guangdong, Hunan, Hubei,
Anhui, Henan, Shanxi, Zhejiang, Jiangsu and Liaoning. All are on GMT+8 in
1970.

In Qinghai there was a zone on GMT+7 with Haiyan, Gonghe, Tongren, Jigzhi,
Xining, and another zone on GMT+6 with Yushi, Zhidoi, Qumalai, Nangqen,
Delingha, Golmud, Lenghu and Mangya.

In Tibet (Xizang) there was a zone on GMT+6 with Lhasa, Chamdo, Shigaise,
Jimsar, Shawan and Hutubi. Another zone on GMT+5 with Pulan, Aheqi, Shufu,
Shule .

On GMT+7 there were also the regions Shaanxi, Nei Mongol and Hainan.

In Gansu it seems the vast majority of the area was on GMT+7 right up until
its westernmost part, where I found a single city Dunhuang on GMT+6. I'm
sure there most be more cities in this area on GMT+6 but I haven't got
around to check it. The cities on GMT+7 were Lanzhou, Linxia, Tianshui,
Pingliang, Wuwei, Zhangye, and Yumen.

My major effort has been on the Xinjiang area, which has a lot of counties,
so it is not easy to determine a map. The cities on GMT+5 were Aksu, Atushi,
Yining, Hetian, Cele, Luopu, Nileke, Zhaosu, Tekesi, Gongliu, Chabuchaer,
Huocheng, Bole, Pishan, Suiding, Yarkand. The cities on GMT+6 were Urumqi,
Turpan, Karamay, Korla, Minfeng, Jinghe, Wusu, Qiemo, Xinyan, Wulanwusu,
Jinghe, Yumin, Tacheng, Tuoli, Emin, Shihezi, Changji, Yanqi, Heshuo,
Tuokexun, Tulufan, Shanshan, Hami, Fukang, Kuitun, Kumukuli, Miquan, Qitai
and Turfan.

The cities in Xinjiang I could find lies in the upper and lower part of the
region, while there is a central zone where I could not find any cities that
coincided with astro.com, but this might also be because it is a big desert
area. Many counties have a name that corresponds to the city name also, so I
could often find it that way, but not for the following counties:

Awati  40.11 80.57
Shaya  40.53 81.43
Kuche  41.77 83.51
Xinhe  41.34 82.13
Baicheng  42.07 81.97
Wensu  41.59 80.38
Wushi  41.20 79.13
Luntai  41.70 84.65
Yuli  40.83 87.00
Hejing  42.88 85.32

The coordinates above correspond to the approximate center of the county.
I'm looking for cities near these county centers that would lie inside the
county and exist in www.astro.com to produce a GMT offset for 1970. Can
anyone help?

Unfortunately there is apparently no "show nearby cities" or map in
astro.com, so it is a bit of guesswork. The amount of different spelling for
each name is also amazing, but perhaps not if you consider "anglified name",
yughur, pinyin, traditional chinese, kazakh and uzbekh as valid variations,
probably flavored with a nice collection of typos too.

Regards,
- Jesper

Paul Eggert writes:

-----Original Message-----
From: Paul Eggert [mailto:eggert at cs.ucla.edu] 
Sent: Martes, 27 de Junio de 2006 12:05
To: Jesper Norgaard Welen
Cc: tz at lecserver.nci.nih.gov
Subject: Re: Chinese timezones


For that sort of thing the Shanks & Pottenger database is the best that I
know of, though of course it's not infallible.  They do attempt to cover the
wartime changes.  Shanks was born during Eastern War Time and notes this
fact in the author's bio on his book.

You should be able to determine the zone boundaries yourself, if you have
good maps, by consulting the Atlas Query <http://www.astro.com/cgi/aq.cgi>,
which is an online version of the Shanks & Pottenger database.  For example,
I just verified that according to that database, Harbin was at UTC+0830 on
1970-01-01 00:00.  As far as I know, the only post 1970 change in China was
in May 1980, so if you use any time stamp from 1970 to 1980 you should be
able to wander around the Chinese countryside using that database and
determine where the time zone boundaries were.  (Good luck with the
spellings, though!)