pmix {seacarb}R Documentation

pmix

Description

Calculates the carbonate chemistry after mixing of two water samples with different pCO2

Usage

pmix(flag, var1, var2, pCO2s, wf, S=35, T=20, P=0, Pt=0, Sit=0, k1k2="x", 
	kf="x", ks="d", pHscale="T", b="u74", eos = "eos80", long = 1e+20, lat = 1e+20)

Arguments

flag

select the couple of variables available. The flags which can be used are:

flag = 1 pH and CO2 given

flag = 2 CO2 and HCO3 given

flag = 3 CO2 and CO3 given

flag = 4 CO2 and ALK given

flag = 5 CO2 and DIC given

flag = 6 pH and HCO3 given

flag = 7 pH and CO3 given

flag = 8 pH and ALK given

flag = 9 pH and DIC given

flag = 10 HCO3 and CO3 given

flag = 11 HCO3 and ALK given

flag = 12 HCO3 and DIC given

flag = 13 CO3 and ALK given

flag = 14 CO3 and DIC given

flag = 15 ALK and DIC given

flag = 21 pCO2 and pH given

flag = 22 pCO2 and HCO3 given

flag = 23 pCO2 and CO3 given

flag = 24 pCO2 and ALK given

flag = 25 pCO2 and DIC given

var1

Value of the first variable in mol/kg except for pH and for pCO2 in \muatm

var2

Value of the second variable in mol/kg except for pH

pCO2s

Partial pressure of the high CO2 component in \muatm

wf

Weight fraction of the high CO2 seawater per kg seawater

S

Salinity

T

Temperature in degrees Celsius

P

Hydrostatic pressure in bar (surface = 0)

Pt

Concentration of total phosphate in mol/kg

Sit

Concentration of total silicate in mol/kg

k1k2

"cw" for using K1 and K2 from Cai & Wang (1998), "l" from Lueker et al. (2000), "m02" from Millero et al. (2002), "m06" from Millero et al. (2006), "m10" from Millero (2010), "mp2" from Mojica Prieto et al. (2002), "p18" from Papadimitriou et al. (2018), "r" from Roy et al. (1993), "sb21" from Shockman & Byrne (2021), "s20" from Sulpis et al. (2020), and "w14" from Waters et al. (2014). "x" is the default flag; the default value is then "l", except if T is outside the range 2 to 35oC and/or S is outside the range 19 to 43. In these cases, the default value is "w14".

kf

"pf" for using Kf from Perez and Fraga (1987) and "dg" for using Kf from Dickson and Riley (1979 in Dickson and Goyet, 1994). "x" is the default flag; the default value is then "pf", except if T is outside the range 9 to 33oC and/or S is outside the range 10 to 40. In these cases, the default is "dg".

ks

"d" for using Ks from Dickon (1990), "k" for using Ks from Khoo et al. (1977), default is "d"

pHscale

choice of pH scale: "T" for using the total scale, "F" for using the free scale and "SWS" for using the seawater scale, default is total scale

b

Concentration of total boron. "l10" for the Lee et al. (2010) formulation or "u74" for the Uppstrom (1974) formulation, default is "u74".

eos

"teos10" to specify T and S according to Thermodynamic Equation Of Seawater - 2010 (TEOS-10); "eos80" to specify T and S according to EOS-80.

long

longitude of data point, used when eos parameter is "teos10" as a conversion parameter from absolute to practical salinity.

lat

latitude of data point, used when eos parameter is "teos10".

Details

The Lueker et al. (2000) constants for K1 and K2, the Perez and Fraga (1987) constant for Kf and the Dickson (1990) constant for Ks are recommended by Dickson et al. (2007). It is, however, critical to consider that each formulation is only valid for specific ranges of temperature and salinity:

For K1 and K2:

For Kf:

For Ks:

The arguments can be given as a unique number or as vectors. If the lengths of the vectors are different, the longer vector is retained and only the first value of the other vectors is used. It is recommended to use either vectors with the same dimension or one vector for one argument and numbers for the other arguments.

Pressure corrections and pH scale:

long and lat are used as conversion parameters from absolute to practical salinity: when seawater is not of standard composition, practical salinity alone is not sufficient to compute absolute salinity and vice-versa. One needs to know the density. When long and lat are given, density is inferred from WOA silicate concentration at given location. When they are not, an arbitrary geographic point is chosen: mid equatorial Atlantic. Note that this implies an error on computed salinity up to 0.02 g/kg.

Value

The function returns a data frame containing the following columns:

comment

The initial or final state water

S

Salinity

T

Temperature in degrees Celsius

P

Pressure in bar

pH

pH

CO2

CO2 concentration (mol/kg)

pCO2

pCO2, CO2 partial pressure (\muatm)

fCO2

fCO2, CO2 fugacity (\muatm)

HCO3

HCO3 concentration (mol/kg)

CO3

CO3 concentration (mol/kg)

DIC

DIC concentration (mol/kg)

ALK

ALK, total alkalinity (mol/kg)

OmegaAragonite

Omega aragonite, aragonite saturation state

OmegaCalcite

Omega calcite, calcite saturation state

Note

Warning: pCO2 estimates below 100 m are subject to considerable uncertainty. See Weiss (1974) and Orr et al. (2015)

Author(s)

Jean-Pierre Gattuso and Heloise Lavignejean-pierre.gattuso@imev-mer.fr

References

Cai W. J., and Wang Y., 1998. The chemistry, fluxes, and sources of carbon dioxide in the estuarine waters of the Satilla and Altamaha Rivers, Georgia. Limnology and Oceanography 43, 657-668.

Dickson A. G. and Riley J. P., 1979 The estimation of acid dissociation constants in seawater media from potentiometric titrations with strong base. I. The ionic product of water. Marine Chemistry 7, 89-99.

Dickson A. G., 1990 Standard potential of the reaction: AgCI(s) + 1/2H2(g) = Ag(s) + HCI(aq), and the standard acidity constant of the ion HSO4 in synthetic sea water from 273.15 to 318.15 K. Journal of Chemical Thermodynamics 22, 113-127.

Dickson A. G., Sabine C. L. and Christian J. R., 2007 Guide to best practices for ocean CO2 measurements. PICES Special Publication 3, 1-191.

Gattuso J.-P. and Lavigne H., 2009. Perturbation experiments to investigate the impact of ocean acidification: approaches and software tools. Biogeosciences 6, 4413-4439.

Khoo H. K., Ramette R. W., Culberson C. H. and Bates R. G., 1977 Determination of Hydrogen Ion Concentration in Seawater from 5 to 40oC: Standard Potentials at Salinities from 20 to 45. Analytical Chemistry 49, 29-34.

Lee K., Tae-Wook K., Byrne R.H., Millero F.J., Feely R.A. and Liu Y-M, 2010 The universal ratio of the boron to chlorinity for the North Pacific and North Atlantoc oceans. Geochimica et Cosmochimica Acta 74 1801-1811.

Millero F. J., 1995 Thermodynamics of the carbon dioxide system in the oceans. Geochimica Cosmochimica Acta 59: 661-677.

Millero F. J., 2010 Carbonate constant for estuarine waters. Marine and Freshwater Research 61: 139-142.

Millero F. J., Graham T. B., Huang F., Bustos-Serrano H. and Pierrot D., 2006 Dissociation constants of carbonic acid in seawater as a function of salinity and temperature. Marine Chemistry 100, 80-84.

Orr J. C., Epitalon J.-M. and Gattuso J.-P., 2015. Comparison of seven packages that compute ocean carbonate chemistry. Biogeosciences 12, 1483-1510.

Uppstrom L.R., 1974 The boron/chlorinity ratio of the deep-sea water from the Pacific Ocean. Deep-Sea Research I 21 161-162.

Waters, J., Millero, F. J., and Woosley, R. J., 2014. Corrigendum to “The free proton concentration scale for seawater pH”, [MARCHE: 149 (2013) 8-22], Marine Chemistry 165, 66-67.

Examples

pmix(flag=24, var1=384, var2=2302e-6, pCO2s=1e6, wf=0.003, S=34.3, 
	T=16, P=0, pHscale="T", kf="pf", k1k2="l", ks="d", b="u74")

[Package seacarb version 3.3.3 Index]