pH of seawater

Marion, G. M.; Millero, Frank J.; Camões, Maria Filomena; Spitzer, Petra; Feistel, Rainer; Chen, Chen‐Tung Arthur

doi:10.1016/j.marchem.2011.04.002

Cited by 199 publications

(115 citation statements)

References 42 publications

Supporting

Mentioning

108

Contrasting

Unclassified

Order By: Relevance

“…Hansson (1973), Bates and Culberson (1977), Khoo et al (1977), Dickson and Riley (1979), Bates (1982) or Dickson (1990), the classical review papers by Dickson (1984Dickson ( , 1993, or standard textbooks (e.g. Zeebe and Wolf-Gladrow, 2001), there are also several recent papers on the subject, such as the reviews by Dickson (2010) and Marion et al (2011) or the research paper by Waters and Millero (2013). In the following sections, we will therefore only give a comparatively general overview, which we have nevertheless tried to keep as selfconsistent as possible.…”

Section: Ph-scale Considerationsmentioning

confidence: 99%

Mathematics of the total alkalinity–pH equation – pathway to robust and universal solution algorithms: the SolveSAPHE package v1.0.1

Munhoven¹

2013

Geosci. Model Dev.

View full text Add to dashboard Cite

Abstract. The total alkalinity-pH equation, which relates total alkalinity and pH for a given set of total concentrations of the acid-base systems that contribute to total alkalinity in a given water sample, is reviewed and its mathematical properties established. We prove that the equation function is strictly monotone and always has exactly one positive root. Different commonly used approximations are discussed and compared. An original method to derive appropriate initial values for the iterative solution of the cubic polynomial equation based upon carbonate-borate-alkalinity is presented. We then review different methods that have been used to solve the total alkalinity-pH equation, with a main focus on biogeochemical models. The shortcomings and limitations of these methods are made out and discussed. We then present two variants of a new, robust and universally convergent algorithm to solve the total alkalinity-pH equation. This algorithm does not require any a priori knowledge of the solution. SolveSAPHE (Solver Suite for Alkalinity-PH Equations) provides reference implementations of several variants of the new algorithm in Fortran 90, together with new implementations of other, previously published solvers. The new iterative procedure is shown to converge from any starting value to the physical solution. The extra computational cost for the convergence security is only 10-15 % compared to the fastest algorithm in our test series.

show abstract

Section: Ph-scale Considerationsmentioning

confidence: 99%

Mathematics of the total alkalinity–pH equation – pathway to robust and universal solution algorithms: the SolveSAPHE package v1.0.1

Munhoven¹

2013

Geosci. Model Dev.

View full text Add to dashboard Cite

show abstract

“…For oceanographic applications, the total and seawater scales are mostly used with a reasonably well-defined conversion routine between them. Recent recommendations are to report the pH of seawater on the free scale (Marion et al, 2011). The discrete pCO 2 and discrete pH measurements have many commonalities as parameters for constraining the inorganic carbon system and for detecting change (McElligott et al, 1998).…”

Section: Acknowledgmentsmentioning

confidence: 99%

Changes in deep-water CO2 concentrations over the last several decades determined from discrete pCO2measurements

Wanninkhof

Park

Takahashi

et al. 2013

Deep Sea Research Part I: Oceanographic Research Papers

View full text Add to dashboard Cite

a b s t r a c tDetection and attribution of hydrographic and biogeochemical changes in the deep ocean are challenging due to the small magnitude of their signals and to limitations in the accuracy of available data. However, there are indications that anthropogenic and climate change signals are starting to manifest at depth. The deep ocean below 2000 m comprises about 50% of the total ocean volume, and changes in the deep ocean should be followed over time to accurately assess the partitioning of anthropogenic carbon dioxide (CO 2 ) between the ocean, terrestrial biosphere, and atmosphere. Here we determine the changes in the interior deep-water inorganic carbon content by a novel means that uses the partial pressure of CO 2 measured at 20 1C, pCO 2 (20), along three meridional transects in the Atlantic and Pacific oceans. These changes are measured on decadal time scales using observations from the World Ocean Circulation Experiment (WOCE)/World Hydrographic Program (WHP) of the 1980s and 1990s and the CLIVAR/CO 2 Repeat Hydrography Program of the past decade. The pCO 2 (20) values show a consistent increase in deep water over the time period. Changes in total dissolved inorganic carbon (DIC) content in the deep interior are not significant or consistent, as most of the signal is below the level of analytical uncertainty. Using an approximate relationship between pCO 2 (20) and DIC change, we infer DIC changes that are at the margin of detectability. However, when integrated on the basin scale, the increases range from 8-40% of the total specific water column changes over the past several decades. Patterns in chlorofluorocarbons (CFCs), along with output from an ocean model, suggest that the changes in pCO 2 (20) and DIC are of anthropogenic origin.Published by Elsevier Ltd.

show abstract

“…of which is related to the pH of the sample solution it contains, while the latter involves relating changes in the optical absorption spectrum of an indicator dye to pH. The pros and cons for both methods have been evaluated in the literature [12,13]. Electrometric methods have been extensively studied and used in practice for many decades.…”

Section: Introductionmentioning

confidence: 99%

“…Electrometric methods have been extensively studied and used in practice for many decades. However, the existence of a liquid junction potentials is still a major source of uncertainty in quantifying the pH of aqueous solutions [13]. Some experimental methods have been developed to minimise liquid junction potentials, such as introducing salt bridges and using precise pH buffers for calibration.…”

Section: Introductionmentioning

confidence: 99%

The pH of CO2-saturated water at temperatures between 308K and 423K at pressures up to 15MPa

Cheng

Crawshaw

Maitland

et al. 2013

The Journal of Supercritical Fluids

149

View full text Add to dashboard Cite

pH of seawater

Cited by 199 publications

References 42 publications

Mathematics of the total alkalinity–pH equation – pathway to robust and universal solution algorithms: the SolveSAPHE package v1.0.1

Mathematics of the total alkalinity–pH equation – pathway to robust and universal solution algorithms: the SolveSAPHE package v1.0.1

Changes in deep-water CO2 concentrations over the last several decades determined from discrete pCO2measurements

The pH of CO2-saturated water at temperatures between 308K and 423K at pressures up to 15MPa

Contact Info

Product

Resources

About