Seawater Thermal Expansion Coefficient

Compute \(\alpha\), the thermal expansion coefficient for seawater.

Usage

swAlpha(
  salinity,
  temperature = NULL,
  pressure = 0,
  longitude = NULL,
  latitude = NULL,
  eos = getOption("oceEOS", default = "gsw")
)

Arguments

salinity: either practical salinity (in which case temperature and pressure must be provided) or an oce object (in which case salinity, etc. are inferred from the object).
temperature: in-situ temperature (\(^\circ\)C), defined on the ITS-90 scale; see “Temperature units” in the documentation for swRho().
pressure: pressure (dbar)
longitude: longitude of observation (only used if eos="gsw"; see “Details”).
latitude: latitude of observation (only used if eos="gsw"; see “Details”).
eos: equation of state, either "unesco" or "gsw".

Value

Value in 1/degC.

References

The eos="unesco" formulae are based on the UNESCO equation of state, but are formulated empirically by Trevor J. McDougall, 1987, Neutral Surfaces, Journal of Physical Oceanography, volume 17, pages 1950-1964. The eos="gsw" formulae come from GSW; see references in the swRho() documentation.

Other functions that calculate seawater properties: T68fromT90(), T90fromT48(), T90fromT68(), computableWaterProperties(), locationForGsw(), swAbsoluteSalinity(), swAlphaOverBeta(), swBeta(), swCSTp(), swConservativeTemperature(), swDepth(), swDynamicHeight(), swLapseRate(), swN2(), swPressure(), swRho(), swRrho(), swSCTp(), swSR(), swSTrho(), swSigma(), swSigma0(), swSigma1(), swSigma2(), swSigma3(), swSigma4(), swSigmaT(), swSigmaTheta(), swSoundAbsorption(), swSoundSpeed(), swSpecificHeat(), swSpice(), swSpiciness0(), swSpiciness1(), swSpiciness2(), swSstar(), swTFreeze(), swTSrho(), swThermalConductivity(), swTheta(), swViscosity(), swZ()

Author

Dan Kelley