sw.depth {oce} | R Documentation |
Compute depth from pressure and latitude.
d <- sw.depth(ctd) d <- sw.depth(p, lat, degrees=TRUE)
ctd |
an object of class "ctd ". |
p |
Pressure [dbar] |
lat |
Latitude in degN or radians north of the equator. |
degrees |
Flag indicating whether degrees are used for latitude;
if set to FALSE , radians are used. |
In the first form, the argument is a ctd
object, from
which the pressure and latitude are extracted and used to for the
calculation.
The information given below is adapted from the fortran code at http://sam.ucsd.edu/sio210/propseawater/ppsw_fortran/ppsw.f, on which this R code was based.
Depth in meters from pressure in decibars using Saunders and Fofonoff's method, with the formula refitted for 1980 equation of state
Check value: depth = 9712.653 m for p=10000 decibars, latitude=30 deg above for standard ocean: t=0 deg. celsuis ; s=35 (ipss-78)
Depth [m].
Dan Kelley
(authors), 1976, (title), Deep-Sea Res., 23, 109-111.
d <- sw.depth(10, 45);