有没有一种简单的方法来确定用户所在的半球？

I'm working on a project which includes seasonal content, and we're thinking of determining the user's location to work out what season it is for them. The obvious way of doing this is to Geo-locate their IP, then grab the latitude. > 0 is Northern hemisphere, and < 0 is Southern. I'm working on a project which includes seasona