# gsw_z_from_p

    height from pressure (48-term equation)

## Contents

- USAGE:
- DESCRIPTION:
- INPUT:
- OUTPUT:
- EXAMPLE:
- AUTHOR:
- VERSION NUMBER:
- REFERENCES:

## USAGE:

    z = gsw_z_from_p(p,lat,{geo_strf_dyn_height})

## DESCRIPTION:

    Calculates height from sea pressure using the computationally-efficient
    48-term expression for density in terms of SA, CT and p. (McDougall et
    al., 2013).
    Note. Height z is NEGATIVE in the ocean. ie. Depth is -z.
     Depth is not used in the GSW computer software library.

    Click for a more detailed description of calculating
    height from pressure.

## INPUT:

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

    OPTIONAL:
    geo_strf_dyn_height = dynamic height                          [ m2/s^2 ]

    lat  =  latitude in decimal degrees north                [ -90 ... +90 ]

    lat may have dimensions 1x1 or Mx1 or 1xN or MxN, where p is MxN.

## OUTPUT:

    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.

## EXAMPLE:

    p =  [   10;   50;  125;  250;  600; 1000;]
    lat = 4;

    z = gsw_z_from_p(p,lat)

    z =

      1.0e+002 *

      -0.099445831334188
      -0.497180888338818
      -1.242726230109135
      -2.484700703230813
      -5.958254446096435
      -9.920921779551200

## AUTHOR:

    Trevor McDougall, Claire Roberts-Thomson & Paul Barker.
                                                       [ help@teos-10.org ]

## VERSION NUMBER:

    3.02 (17th November, 2012)

## 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., P.M. Barker, R. Feistel and D.R. Jackett, 2013:  A
     computationally efficient 48-term expression for the density of
     seawater in terms of Conservative Temperature, and related properties
     of seawater.  To be submitted to J. Atm. Ocean. Technol., xx, yyy-zzz.

    Moritz (2000) Goedetic reference system 1980. J. Geodesy, 74, 128-133.

    This software is available from http://www.TEOS-10.org