Calculate dissolved nitrous oxide saturation

Calculates the dissolved nitrous oxide concentration in equilibrium with the atmosphere from water temperature, barometric pressure, and salinity, using the Weiss and Price (1980) solubility function for nitrous oxide as a non-ideal atmospheric trace gas.

Usage

calc_N2Osat(
  temp_water,
  atmo_press,
  units = "atm",
  salinity = 0,
  xN2O_ppm = 0.338,
  out_units = "umol/L"
)

Arguments

temp_water

Numeric vector. Water temperature in degrees Celsius.

atmo_press

Numeric vector. Barometric pressure at the site.

units

Character string. Units of atmo_press. See convert_pressure() for accepted pressure units. Defaults to "atm".

salinity

Numeric vector. Salinity in parts per thousand. Defaults to freshwater (0).

xN2O_ppm

Numeric vector. Dry-air mole fraction of N2O in parts per million. Defaults to 0.338, an approximate present-day value; override it with a measured atmospheric value where available.

out_units

Character string. Output concentration units, either "umol/L" (the default) or "mg/L".

Value

Numeric vector of dissolved N2O saturation in the requested units.

Details

The equilibrium concentration is \(C^* = x' F\), where \(x'\) is the dry-air mole fraction and \(F\) is the moist-air solubility function of Weiss and Price (1980), evaluated with their volumetric coefficients (Table II). A vapor-pressure correction scales the 1 atm result to the supplied barometric pressure.

References

Weiss, R.F., and Price, B.A. (1980). Nitrous oxide solubility in water and seawater. Marine Chemistry, 8, 347-359.

See also

calc_O2sat(), calc_CO2sat(), calc_CH4sat(), calc_N2sat(), calc_Arsat()

Examples

calc_N2Osat(temp_water = 20, atmo_press = 1, salinity = 0)
#> [1] 0.009460648

calc_N2Osat(
  temp_water = c(5, 15, 25),
  atmo_press = 101.325,
  units = "kPa",
  xN2O_ppm = 0.338,
  out_units = "mg/L"
)
#> [1] 0.0007113589 0.0004918582 0.0003560558