The boat channel: Difference between revisions
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[[File:Boat-channel-cross-section.jpg|thumb|300px]] | [[File:Boat-channel-cross-section.jpg|thumb|300px]] | ||
[[File:GoogleEarth-landing-channel.png|thumb|300px]] | |||
The so-called '''boat channel''' runs south out of [[Tatiman Passage]], parallel to the shoreline. There is a similar channel running north out of the passage along the [[Nutiran]] shore. | The so-called '''boat channel''' runs south out of [[Tatiman Passage]], parallel to the shoreline. There is a similar channel running north out of the passage along the [[Nutiran]] shore. | ||
The channels | The channels are the result of a "longshore current" scouring a two- to four-foot depression in the underlying coral close to the sand line of the beaches. When waves strike a shoreline at an angle, they tend to produce a current that runs parallel to the shoreline. The effect of prevailing winds, the longshore current, and gravity causes [http://en.wikipedia.org/wiki/Longshore_drift "longshore drift"] of beaches. | ||
The path of water to escape the reef runs along the shore until such a point where it can find its way off the reef in a natural channel 90 degrees to the beach. | |||
These channels in the sand or coral at the edge of the beach formed by the longshore drift have proven useful for small boat navigation parallel to the beach, hence the name "boat channel." Water may remain in the boat channel even at low tide. | |||
[[TIGHAR]] has sometimes used the term "boat channel" to refer to [[the landing| channel blasted through the reef]], oriented perpendicular to the shore, that allowed small boats to cross the reef and land close to the sand line. | |||
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[[Category:Nikumaroro]] | [[Category:Nikumaroro]] | ||
Revision as of 18:05, 22 October 2009
The so-called boat channel runs south out of Tatiman Passage, parallel to the shoreline. There is a similar channel running north out of the passage along the Nutiran shore.
The channels are the result of a "longshore current" scouring a two- to four-foot depression in the underlying coral close to the sand line of the beaches. When waves strike a shoreline at an angle, they tend to produce a current that runs parallel to the shoreline. The effect of prevailing winds, the longshore current, and gravity causes "longshore drift" of beaches.
The path of water to escape the reef runs along the shore until such a point where it can find its way off the reef in a natural channel 90 degrees to the beach.
These channels in the sand or coral at the edge of the beach formed by the longshore drift have proven useful for small boat navigation parallel to the beach, hence the name "boat channel." Water may remain in the boat channel even at low tide.
TIGHAR has sometimes used the term "boat channel" to refer to channel blasted through the reef, oriented perpendicular to the shore, that allowed small boats to cross the reef and land close to the sand line.