sw_svel: Velocity of the Sound in Seawater
In marelac: Tools for Aquatic Sciences

Description Usage Arguments Value Note Author(s) References See Also Examples

Computes the velocity of the sound in seawater, using the UNESCO 1983 polynomial or based on the Gibbs function.

Valid for salinity from 0 to 40, temperature from 0 to 40 dgC, pressure from 1 to 1000 bars.

1 2	sw_svel(S = 35, t = 25, p = P-1.013253, P = 1.013253, method = c("Gibbs", "UNESCO"))

`S`	Salinity, when `method` = `"UNESCO"`: practical salinity (-) else absolute salinity (g/kg),
`t`	Temperature, degrees C,
`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

Sound velocity, in m / sec.

Sound velocity for S = 40, t = 40, p = 1000 is 1731.995 using UNESCO polynomial.

Karline Soetaert <karline.soetaert@nioz.nl>

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.

sw_adtgrad, sw_alpha, sw_beta, sw_comp, sw_conserv, sw_cp, sw_dens, sw_depth, sw_enthalpy, sw_entropy, sw_gibbs, sw_kappa, sw_kappa_t, sw_sfac, 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 (-)

sw_svel(t = 40, S = 40, p = 10:20, method = "UNESCO")

# Check value UNESCO
sw_svel(t = 40, S = 40, p = 1000, method = "UNESCO")  # 1731.995
sw_svel(t = 0, S = 40, p = 0, method = "UNESCO")      # 1455.8

sw_svel(t = 40, S = 25, p = 1000, method = "UNESCO")  # 1719.2
sw_svel(t = 40, S = 25, p = 0, method = "UNESCO")     # 1553.4
sw_svel(t = 0, S = 25, p = 0, method = "UNESCO")      # 1435.8


# Check value Gibbs
sw_svel(S = 35.7, t = 25.5, p = 102.3)              # 1552.93372863425