org.jscience.earth
Class EarthSeaWater

java.lang.Object
  extended by org.jscience.earth.EarthSeaWater

public final class EarthSeaWater
extends java.lang.Object

Sea water properties as a function of salinity, temperature and pressure. Density is computed using the 1980 definition of Equation of State (EOS80). Units are:


Field Summary
static double STANDARD_CONDUCTIVITY
          Conductivity (in mS/cm) of a standard sea water sample.
 
Method Summary
static double adiabeticTemperatureGradient(double S, double T, double P)
          Compute adiabetic temperature gradient as a function of salinity, temperature and pressure.
static double conductivity(double S, double T, double P)
          Compute conductivity as a function of salinity, temperature and pressure.
static double density(double S, double T, double P)
          Compute density as a function of salinity, temperature and pressure.
static double densitySigmaT(double S, double T, double P)
          Compute density sigma-T as a function of salinity, temperature and pressure.
static double depth(double P, double lat)
          Compute depth as a function of pressure and latitude.
static double fusionTemperature(double S, double P)
          Compute fusion temperature (melting point) as a function of salinity and pressure.
static double getIrradiance(float depth)
           
static double getWavelengthAttenuation(float frequency)
           
static double salinity(double C, double T, double P)
          Compute salinity as a function of conductivity, temperature and pressure.
static double saturationO2(double S, double T)
          Compute saturation in disolved oxygen as a function of salinity and temperature.
static double soundVelocity(double S, double T, double P)
          Compute sound velocity as a function of salinity, temperature and pressure.
static double specificHeat(double S, double T, double P)
          Compute specific heat as a function of salinity, temperature and pressure.
static double volume(double S, double T, double P)
          Compute volume as a function of salinity, temperature and pressure.
static double volumeAnomaly(double S, double T, double P)
          Compute volumic anomaly as a function of salinity, temperature and pressure.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

STANDARD_CONDUCTIVITY

public static final double STANDARD_CONDUCTIVITY
Conductivity (in mS/cm) of a standard sea water sample. S is for Siemmens (or Mho, its the same...).

See Also:
Constant Field Values
Method Detail

getWavelengthAttenuation

public static double getWavelengthAttenuation(float frequency)

density

public static double density(double S,
                             double T,
                             double P)
Compute density as a function of salinity, temperature and pressure.

Parameters:
S - Salinity PSS-78 (0 to 42)
T - Temperature ITS-68 (-2 to 40�C)
P - Pressure in decibars (0 to 105 dbar), not including atmospheric pressure.
Returns:
Density (kg/m�).

densitySigmaT

public static double densitySigmaT(double S,
                                   double T,
                                   double P)
Compute density sigma-T as a function of salinity, temperature and pressure. Density Sigma-T is equivalent to the true density minus 1000 kg/m�, and has typical values around 35. This computation avoid some rouding errors occuring in the true density computation.

Parameters:
S - Salinity PSS-78 (0 to 42)
T - Temperature ITS-68 (-2 to 40�C)
P - Pressure in decibars (0 to 105 dbar), not including atmospheric pressure.
Returns:
Density Sigma-T (kg/m�).

volume

public static double volume(double S,
                            double T,
                            double P)
Compute volume as a function of salinity, temperature and pressure. This quantity if the inverse of density. This method is equivalent to 1/density(S,T,P).

Parameters:
S - Salinity PSS-78 (0 to 42)
T - Temperature ITS-68 (-2 to 40�C)
P - Pressure in decibars (0 to 105 dbar), not including atmospheric pressure.
Returns:
Volume (m�/kg).

volumeAnomaly

public static double volumeAnomaly(double S,
                                   double T,
                                   double P)
Compute volumic anomaly as a function of salinity, temperature and pressure. Volumic anomaly is defined as the sea water sample's volume minus a standard sample's volume, where the standard sample is a sample of salinity 35, temperature 0�C and the same pressure. In pseudo-code, volumeAnomaly is equivalent to volume(S,T,P)-volume(35,0,P).

Parameters:
S - Salinity PSS-78 (0 to 42)
T - Temperature ITS-68 (-2 to 40�C)
P - Pressure in decibars (0 to 105 dbar), not including atmospheric pressure.
Returns:
Volumic anomaly (m�/kg).

salinity

public static double salinity(double C,
                              double T,
                              double P)
Compute salinity as a function of conductivity, temperature and pressure.

Parameters:
C - Conductivity in mS/cm (milli-Siemmens by centimeters). Multiply par STANDARD_CONDUCTIVITY if C is not a real conductivity, but instead the ratio between the sample's conductivity and the standard sample's conductivity.
T - Temperature ITS-68 (-2 to 40�C)
P - Pressure in decibars (0 to 105 dbar), not including atmospheric pressure.
Returns:
Salinity PSS-78.

conductivity

public static double conductivity(double S,
                                  double T,
                                  double P)
Compute conductivity as a function of salinity, temperature and pressure.

Parameters:
S - Salinity PSS-78 (0 to 42)
T - Temperature ITS-68 (-2 to 40�C)
P - Pressure (0 to 105 dbar), not including atmospheric pressure.
Returns:
Conductivity in mS/cm.

specificHeat

public static double specificHeat(double S,
                                  double T,
                                  double P)
Compute specific heat as a function of salinity, temperature and pressure.

Parameters:
S - Salinity PSS-78.
T - Temperature (�C).
P - Pressure (dbar), not including atmospheric pressure.
Returns:
Specific heat (J/(kg�C)).

fusionTemperature

public static double fusionTemperature(double S,
                                       double P)
Compute fusion temperature (melting point) as a function of salinity and pressure.

Parameters:
S - Salinity PSS-78.
P - Pressure (dbar), not including atmospheric pressure.
Returns:
Melting point (�C).

adiabeticTemperatureGradient

public static double adiabeticTemperatureGradient(double S,
                                                  double T,
                                                  double P)
Compute adiabetic temperature gradient as a function of salinity, temperature and pressure.

Parameters:
S - Salinity PSS-78.
T - Temperature (�C).
P - Pressure (dbar), not including atmospheric pressure.
Returns:
Adiabetic temperature gradient (�C/dbar).

depth

public static double depth(double P,
                           double lat)
Compute depth as a function of pressure and latitude.

Parameters:
P - Pressure (dbar), not including atmospheric pressure.
lat - Latitude in degrees (-90 to 90�)
Returns:
Depth (m).

soundVelocity

public static double soundVelocity(double S,
                                   double T,
                                   double P)
Compute sound velocity as a function of salinity, temperature and pressure.

Parameters:
S - Salinity PSS-78.
T - Temperature (�C).
P - Pressure (dbar), not including atmospheric pressure.
Returns:
Sound velocity (m/s).

saturationO2

public static double saturationO2(double S,
                                  double T)
Compute saturation in disolved oxygen as a function of salinity and temperature.

Parameters:
S - Salinity PSS-78.
T - Temperature (�C).
Returns:
Saturation in disolved oxygen (�mol/kg).

getIrradiance

public static double getIrradiance(float depth)