The international system of units (SI) in oceanography

• UNESCO (1985) The international system of units (SI) in oceanography, UNESCO Technical Papers No. 45, IAPSO Pub. Sci. No. 32, Paris, France.    


• psu : practical salinity unit - unité de salinité - unidad de salinidad -
  1 psu = 1 g (Na+Cl-) / kg of seawater-d'eau de mer-de agua del mar.

The international system of units (SI) 
Système international d’unités (SI)  
Sistema internacional de unidades (SI)  

• Comments - Commentaires - Comentarios :


• longitude et latitude sont exprimées en °, minute, 100e de minute (et non en secondes)


• distance : nautical mile - mille marin - millia nautica - 1 M = 1852 m
  The nautical mile is a special unit employed for marine and aerial navigation to express distance. The conventional value given here was adopted by the First International Extraordinary Hydrographic Conference, Monaco 1929, under the name “International nautical mile”. As yet there is no internationally agreed symbol, but the symbols M, NM, Nm, and nmi are all used; in the table the symbol M is used. The unit was originally chosen, and continues to be used, because one nautical mile on the surface of the Earth subtends approximately one minute of angle at the centre of the Earth, which is convenient when latitude and longitude are measured in degrees and minutes of angle.


• speed - vitesse - velocidad : knot - nœud - nudo : kn 1 kn = (1852/3600) m/s
  The knot is defined as one nautical mile per hour. There is no internationally agreed symbol, but the symbol kn is commonly used.

Système d'unités pifométriques