Marégrafo de Cascais - Cascais, Portugal
Posted by: tmob
N 38° 41.648 W 009° 25.092
29S E 463631 N 4282917
Cascais tide gauge is one of the few in the world that it is still working since the 19th century.
Waymark Code: WMDKC7
Location: Lisboa, Portugal
Date Posted: 01/25/2012
Views: 8
«Situated next to the marina, Cascais tide gauge is one of the few in the world that it is still working since the 19th century.
The average sea water level is measured here through a buoy connected to a register, a paper roll rolls to the rhythm set by a clock, the pen registers the buoy level in this paper.
It was in this tide gauge that the vertical control “reference zero” of Portuguese mapping was adapted.
It continues to be used by investigators all over the world to study average sea level oscillations.
Cascais tide gauge is opened to guided tours by appointment.»
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