sw_cp: Heat Capacity of Sea Water

sw_cpR Documentation

Heat Capacity of Sea Water

Description

Estimates the heat capacity of seawater.

Valid for S = 0 to 40, T = 0 to 35 dg C

Usage

sw_cp(S = 35, t = 25, p = P-1.013253, P = 1.013253,
      method = c("Gibbs", "UNESCO"))

Arguments

S

Salinity, when method = "UNESCO": practical salinity (-) else absolute salinity (g/kg),

t

Temperature, ^\circC,

p

gauge or applied pressure, pressure referenced against the local atmospheric pressure, bar

P

true pressure, bar

method

When "UNESCO", uses the UNESCO (1983) polynomial, when "Gibbs", based on the gibbs functions as in Feistel, 2008

Value

Heat capacity, in J kg^{-1} dgC^{-1}

Note

p is applied pressure, 0 bar at sea surface.

when using UNESCO polynomial, cp for S = 40, T = 40, P = 1000 is 3849.5 J/(kg dg C).

Author(s)

Karline Soetaert <karline.soetaert@nioz.nl>

References

Fofonoff NP and Millard RC Jr, 1983. Algorithms for computation of fundamental properties of seawater. UNESCO technical papers in marine science, 44, 53 pp.
http://unesdoc.unesco.org/images/0005/000598/059832EB.pdf

Feistel R, 2008. A Gibbs function for seawater thermodynamics for -6 to 80 dgC and salinity up to 120 g/kg. Deep-Sea Research I, 55, 1639-1671.

McDougall TJ, Feistel R, Millero FJ, Jackett DR, Wright DG, King BA, Marion GM, Chen C-T A and Spitzer P, 2009. Calculation of the Thermophysical Properties of Seawater, Global Ship-based Repeat Hydrography Manual, IOCCP Report No. 14, ICPO Publication Series no. 134.

See Also

sw_adtgrad, sw_alpha, sw_beta, sw_comp, sw_conserv, sw_dens, sw_depth, sw_enthalpy, sw_entropy, sw_gibbs, sw_kappa, sw_kappa_t, sw_sfac, sw_svel, sw_tfreeze, sw_tpot

convert_PStoAS, to convert from practical salinity (-) to absolute salinity (g/kg)

convert_AStoPS, to convert from absolute salinity (g/kg) to practical salinity (-)

Examples

sw_cp(S = 40, t = 40, p = 1000, method="UNESCO")  # 3849.5

# Check value Gibbs function
sw_cp(35.7,25.5,102.3)#3974.42541259729

# Check values UNESCO
sw_cp(S = 25, t = 10, p = 0,    method = "UNESCO")  # 4041.8
sw_cp(S = 25, t = 10, p = 1000, method = "UNESCO")  # 3842.3
sw_cp(S = 25, t = 30, p = 0,    method = "UNESCO")  # 4049.1

sw_cp(S = 40, t = 10, p = 0, method = "UNESCO")  # 3959.3


marelac documentation built on Sept. 25, 2023, 5:06 p.m.