ONERC
Observatoire National sur les Effets du Réchauffment Climatique (National observatory of the effects of global warming).
OPECST
Office parlementaire d'évaluation des choix scientifiques et technologiques (Parliamentary office for the evaluation of scientific and technological choices).
Perigean spring tide
Maximum amplitude of the tide around the passage of the Moon at its perigee.
perigee
Closest point of the orbit to a focus.
PNA
Ports Normands Associés (associated Norman ports).
Polar axis
The Earth's axis of rotation.
Polar distance
Complement at 90° to the declination.
Priming
Period during which the amplitude of the tide increases between neaps and springs.
Proctor's rule
Geometric construction of the tide generating force.
PSMSL
Permanent Service for Mean Sea Level.
Quadrature
Position of the Moon and Sun when their directions with respect to the Earth form a right angle (general term for the first and last quaters).
Radiational component
As opposed to gravitational components, these are components derived from the sun's radiational action.
RAM
Références altimétriques maritimes (hydrographic datums)
Range of tide
Difference in height between successive low and high waters.
Reduced heights
Periodic magnitudes, resulting from an interpolation of heights observed for calculating reduced vectors.
Reduced vectors
Complex numbers representing the component elements of a species (modulus and phase) at a given moment).
REFMAR
Réseaux de référence des observations marégraphiques (Tide gauge observation reference networks).
Response method
Tidal analysis and prediction technique based on admittances.
Right ascension
Angle between the meridian plane of the celestial body and the vernal point, measured anti-clockwise towards the celestial body.
Rising tide
Time interval between a low water and the next high water. Synonym: rising tide, rise, flood.