https://gis.stackexchange.com/questions/211796/if-degrees-is...
I made the above post due to a bug in the GPS on our routers. We had a customer close to the meridian in England.
http://www.thegreenwichmeridian.org/tgm/articles.php?article...
Western hemisphere is negative longitude, eastern hemisphere is positive. If your degrees are 0 (within ~100km? I can't remember exactly), then you still need to know if you're east or west of the meridian.