Maritime geography is often discussed in terms of
four loosely-defined regions: Riverine, brown water, green water,
and blue water.
The riverine environment consists of all navigable
rivers of interest.
The brown water environment consists of the
the coast and estuarial
areas to perhaps a hundred miles from shore. It is the most
important maritime arena, including all coastal traffic and
territorial waters, in which are found the great majority of a
, customs, environmental, and economic concerns.
" focuses on coastal operations and primarily takes a
The green water environment extends from the
outer edge of the brown-water zone past any continental
s and island
s; perhaps a thousand miles
" is capable of defense of its nation in depth and is a
significant offensive force within its territory.
The blue water environment extends from the
outer edge of the green-water zone through the global deep ocean
" can project its nation's power throughout the
riverine in Modern Greek (1453-): Ναυτιλιακή