gsw_p_from_z

pressure from height (25-term equation)

Contents

USAGE:

p = gsw_p_from_z(z,lat)

DESCRIPTION:

Calculates sea pressure from height using computationally-efficient
25-term expression for density, in terms of SA, CT and p
(McDougall et al., 2010).
Note. Height (z) is NEGATIVE in the ocean.  Depth is -z.
  Depth is not used in the GSW computer software library.
TEOS-10
Click for a more detailed description of calculating
pressure from height.

INPUT:

z   =  height                                                      [ m ]
 Note. At sea level z = 0, and since z (HEIGHT) is defined
   to be positive upwards, it follows that while z is
   positive in the atmosphere, it is NEGATIVE in the ocean.
lat =  latitude in decimal degrees north                 [ -90 ... +90 ]
lat may have dimensions 1x1 or Mx1 or 1xN or MxN, where z is MxN.

OUTPUT:

 p  =  sea pressure                                             [ dbar ]
       ( ie. absolute pressure - 10.1325 dbar )

EXAMPLE:

z   =  [     10;      50;     125;     250;     600;    1000;]
lat = 4;
p = gsw_p_from_z(z,lat)
p
 1.0e+003 *
 -0.010055217939908
 -0.050271175099730
 -0.125654885697343
 -0.251232845042860
 -0.602440507522266
 -1.003076098067266

AUTHOR:

Trevor McDougall, Claire Roberts-Thomson and Paul Barker.
                                                [ help_gsw@csiro.au ]

VERSION NUMBER:

2.0 (26th August, 2010)

REFERENCES:

IOC, SCOR and IAPSO, 2010: The international thermodynamic equation of
 seawater - 2010: Calculation and use of thermodynamic properties.
 Intergovernmental Oceanographic Commission, Manuals and Guides No. 56,
 UNESCO (English), 196 pp.  Available from the TEOS-10 web site.
McDougall T. J., D. R. Jackett, P. M. Barker, C. Roberts-Thomson, R.
 Feistel and R. W. Hallberg, 2010:  A computationally efficient 25-term
 expression for the density of seawater in terms of Conservative
 Temperature, and related properties of seawater.  To be submitted
 to Ocean Science Discussions.
Saunders, P. M., 1981: Practical conversion of pressure to depth.
 Journal of Physical Oceanography, 11, 573-574.
Moritz (2000) Goedetic reference system 1980. J. Geodesy, 74, 128-133.
This software is available from http://www.TEOS-10.org