How are "international waters" determined?

So there’s a “baseline” that’s basically the low tide line for a body of land.

http://en.wikipedia.org/wiki/Baseline_(sea) (link won’t work right, but you get the idea)

and 12 nautical miles from there is consider territorial waters, which are kind of the extension of the land.

There’s another 12 nautical miles that’s the “contiguous zone” and it’s kind of the buffer between the controlled water and the “high seas” of international waters.

As far as the international law, it seems to be United Nations Convention on the Law of the Sea that lays most of the groundwork.

There’s a handy diagram in a couple of those articles that breaks it down more clearly but those are the basics I think.

The extension of the land by those 12 miles seems to be why countries care to hang on to tiny islands sometimes. It’s not just the land, it’s the waters around the land, the fishing rights for those areas, and the right to go to and from those areas.

Thank you :)

Learned something new.

What will be very interesting is to see just how the Arctic Circle is divvied up as the glaciers retreat.

There’s already been some tension there