Just be aware that this 200 nm principle is exactly that, a
principle. Some remarks:
1. It is 200 nm from the baseline, not from the coast. This probably
won't make much difference, but I wonder whether it makes any all the
same. Especially with big bays that are nevertheless considered to be
inland water (they are inside a baseline) and archipelagic states,
where the baseline is sometimes a line connecting the outer islands.
2. International agreements can alter the 'principle' boundary, or
decide for an entirely new boundary. I am very intrigued by the 'box'
around Spitsbergen, that is the result of a multilateral agreement,
according to that map at
http://www.maritimeboundaries.com/ . It
seems to touch the 'loop hole'.
(The enclave of high seas in the Barentsz Sea has this nickname loop
hole; the one in the Sea of Okhotsk is the peanut hole, the one in
the Bering Sea the donut hole).
Another question, based on this map: why is there an agreed boundary
_across_ the donut hole? Are the high seas divided as well? Strange.
But then again, this map can be wrong. It definitely considers
Rockall and Okinotori-shima/Parece Vela to be starting points for
EEZ's (Kolbeinsey I can't see, but that would only have an effect on
a yet to be decided upon boundary between the Danish and Icelandic
EEZ's in the Denmark Strait). Rockall can only be inhabited by some
guards for photographic purposes and by Greenpeace people, but Parece
Vela is a joke (albeit a joke strenghtened by concrete). So much for
the habitable principle.
Still, Grant, I am very impressed by what you've done here.
Peter S.
--- In BoundaryPoint@y..., granthutchison@c... wrote:
> I'm still ploughing my lonely 200nm furrow out here.
>
> I've been messing around with the GTOPO30 database recently, which
lets me
> generate maps of fixed-width coastal zones automatically. GTOPO30
contains
> elevation data at 30 arcsec intervals for the whole earth, and so
has a
> resolution of one km or less. This seems ideal, since islands that
fall below
> the 1km resolution of the data are unlikely to fit the UN's
requirement for
> "habitable" land from which Exclusive Economic Zones can be
extended.
> But:
> a) GTOPO30 is missing data for a few islands that fall well within
its
> resolving capacity - San Andres & Providencia in the Caribbean are
missing,
> for instance.
> b) Some EEZ claims are based on tiny islands that are not in the
least
> habitable in the conventional sense - the UK bases a chunk of its
EEZ on
> Rockall, for instance.
>
> So after much fiddling, I've been able to generate some nice EEZ
maps, but
> not entirely automatically - some islands have to be put in by hand.
>
> Attached is my first effort at showing the Everone's Land enclaves
within the
> Caribbean EEZs. Land is in black, sea in blue, EEZs in cyan.
> The Gulf of Mexico contains a large area that is more than 200nm
from any
> inhabited land, and the central Caribbean contains another, smaller
area. But
> maps of real-world maritime boundaries generally show the Gulf area
> containing two separate smaller areas of high sea, and none at all
in the
> Caribbean. Why?
> What shuts down the Gulf area seems to be a Mexican claim based on
various
> reefs and cays: Arrecife Alacran, Cayo Nuevo and Cayo Arenas. I've
shown
> these claims in a darker shade of cyan, since I suspect they might
not meet
> the letter of the UN definition. There's also a little rim of
darker cyan in
> the east of the Gulf, arising from the Dry Tortugas. (I do know
these have
> been inhabited in the past, most prominently by the infamous Dr
Mudd, but
> that word "Dry" tends to support my contention that they're not
habitable in
> the strictest sense.)
> The Caribbean high seas enclave is closed off in practice by the
meeting of
> the Columbian and Jamaican EEZs along a treaty line. Presumably the
larger
> extent of these EEZs is based on more cays and reefs: Columbia
claims a raft
> of these east of the San Andres and Porvidencia Islands, and
Jamaica own the
> Pedro and Morant Cays. EEZs constructed around the eastern cays of
Columbia
> and the southern cays of Jamaica completely close off the "high
seas"
> triangle, so again I've mapped it in dark cyan.
> I'm still trying to track down a copy of "Maritime Boundaries of
the World"
> to enlighten by speculation, but meanwhile I'm enjoying what
amounts to
> experimental geography - seeing what the computer generates, and
then
> matching that to what's going on in the real world.
>
> Grant