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Wave exposure definitions

Wave exposure Definitions (from Hiscock, 1990)
EXTREMELY EXPOSED Open coastlines which face into the prevailing wind and receive both wind-driven waves and oceanic swell without any offshore obstructions such as islands or shallows for several thousand kilometres and where deep water is close to the shore (50 m depth contour within about 300 m).
VERY EXPOSED 1) Open coasts which face into prevailing winds and which receive wind-driven waves and oceanic swell without any offshore obstructions for several hundred kilometres, but where deep water is not close to the shore (50 m depth contour further than about 300 m).
2) Open coasts adjacent to extremely exposed sites but which face away from prevailing winds.
EXPOSED 1) Coasts which face the prevailing wind but which have a degree of shelter because of extensive shallow areas offshore, offshore obstructions, or a restricted (less than 90°) window to open water. These sites are not generally exposed to large waves or regular swell. 2) Open coasts facing away from prevailing winds but with a long fetch, and where strong winds are frequent.
MODERATELY EXPOSED Generally coasts facing away from prevailing winds and without a long fetch, but where strong winds can be frequent .
SHELTERED Coasts with a restricted fetch and/or open water window. Coasts can face prevailing winds but with a short fetch (< 20 km) or extensive shallow area offshore, or may face away from prevailing winds.
VERY SHELTERED Coasts with a fetch less than about 3 km where they face prevailing winds or about 20 km where they face away from prevailing winds, or which have offshore obstructions such as reefs or a narrow (< 30°) open water window
EXTREMELY SHELTERED Fully enclosed coasts with a fetch of no more than about 3 km.
ULTRA SHELTERED Fully enclosed coasts with a fetch measured in tens or at most a few hundred metres.