oce (version 0.9-18)

swTFreeze: Seawater freezing temperature

Description

Compute freezing temperature of seawater.

Usage

swTFreeze(salinity, pressure=0,
  longitude=300, latitude=30, saturation_fraction=1,
  eos=getOption("oceEOS", default="gsw"))

Arguments

salinity

either salinity [PSU] or a ctd object from which salinity will be inferred.

pressure

seawater pressure [dbar]

longitude

longitude of observation (only used if eos="gsw"; see Details).

latitude

latitude of observation (only used if eos="gsw"; see Details).

saturation_fraction

saturation fraction of dissolved air in seawater (used only if eos="gsw").

eos

equation of state, either "unesco" [1,2] or "gsw" [3,4].

Value

• Temperature [$^\circ$C], defined on the ITS-90 scale.

Details

In the first form, the argument is a ctd object, from which the salinity and pressure values are extracted and used to for the calculation.

References

[1] Fofonoff, P. and R. C. Millard Jr, 1983. Algorithms for computation of fundamental properties of seawater. Unesco Technical Papers in Marine Science, 44, 53 pp

[2] Gill, A.E., 1982. Atmosphere-ocean Dynamics, Academic Press, New York, 662 pp.

[3] IOC, SCOR, and IAPSO (2010). The international thermodynamic equation of seawater-2010: Calculation and use of thermodynamic properties. Technical Report 56, Intergovernmental Oceanographic Commission, Manuals and Guide.

[4] McDougall, T.J. and P.M. Barker, 2011: Getting started with TEOS-10 and the Gibbs Seawater (GSW) Oceanographic Toolbox, 28pp., SCOR/IAPSO WG127, ISBN 978-0-646-55621-5.

Examples

swTFreeze(salinity=40, pressure=500, eos="unesco") # -2.588567 degC