The effects of biogeochemical processes on oceanic conductivity/salinity/density relationships and the characterization of real seawater
As seawater circulates through the global ocean, its relative composition undergoes small variations. This results in changes to the conductivity/salinity/density relationship, which is currently well-defined only for Standard Seawater obtained from a particular area in the North Atlantic. These cha...
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ftcopernicus:oai:publications.copernicus.org:os7223 2023-05-15T17:34:22+02:00 The effects of biogeochemical processes on oceanic conductivity/salinity/density relationships and the characterization of real seawater Pawlowicz, R. Wright, D. G. Millero, F. J. 2018-01-15 application/pdf https://doi.org/10.5194/os-7-363-2011 https://os.copernicus.org/articles/7/363/2011/ eng eng doi:10.5194/os-7-363-2011 https://os.copernicus.org/articles/7/363/2011/ eISSN: 1812-0792 Text 2018 ftcopernicus https://doi.org/10.5194/os-7-363-2011 2020-07-20T16:26:08Z As seawater circulates through the global ocean, its relative composition undergoes small variations. This results in changes to the conductivity/salinity/density relationship, which is currently well-defined only for Standard Seawater obtained from a particular area in the North Atlantic. These changes are investigated here by analysis of laboratory experiments in which salts are added to seawater, by analysis of oceanic observations of density and composition anomalies, and by mathematical investigation using a model relating composition, conductivity, and density of arbitrary seawaters. Mathematical analysis shows that understanding and describing the effect of changes in relative composition on operational estimates of salinity using the Practical Salinity Scale 1978 and on density using an equation of state for Standard Seawater require the use of a number of different salinity variables and a family of haline contraction coefficients. These salinity variables include an absolute Salinity S A soln , a density salinity S A dens , the reference salinity S R , and an added-mass salinity S A add . In addition, a new salinity variable S ∗ is defined, which represents the preformed salinity of a Standard Seawater component of real seawater to which biogeochemical processes add material. In spite of this complexity, observed correlations between different ocean biogeochemical processes allow the creation of simple formulas that can be used to convert between the different salinity and density measures, allowing for the operational reduction of routine oceanographic observations. Text North Atlantic Copernicus Publications: E-Journals Ocean Science 7 3 363 387 |
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Open Polar |
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Copernicus Publications: E-Journals |
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ftcopernicus |
language |
English |
description |
As seawater circulates through the global ocean, its relative composition undergoes small variations. This results in changes to the conductivity/salinity/density relationship, which is currently well-defined only for Standard Seawater obtained from a particular area in the North Atlantic. These changes are investigated here by analysis of laboratory experiments in which salts are added to seawater, by analysis of oceanic observations of density and composition anomalies, and by mathematical investigation using a model relating composition, conductivity, and density of arbitrary seawaters. Mathematical analysis shows that understanding and describing the effect of changes in relative composition on operational estimates of salinity using the Practical Salinity Scale 1978 and on density using an equation of state for Standard Seawater require the use of a number of different salinity variables and a family of haline contraction coefficients. These salinity variables include an absolute Salinity S A soln , a density salinity S A dens , the reference salinity S R , and an added-mass salinity S A add . In addition, a new salinity variable S ∗ is defined, which represents the preformed salinity of a Standard Seawater component of real seawater to which biogeochemical processes add material. In spite of this complexity, observed correlations between different ocean biogeochemical processes allow the creation of simple formulas that can be used to convert between the different salinity and density measures, allowing for the operational reduction of routine oceanographic observations. |
format |
Text |
author |
Pawlowicz, R. Wright, D. G. Millero, F. J. |
spellingShingle |
Pawlowicz, R. Wright, D. G. Millero, F. J. The effects of biogeochemical processes on oceanic conductivity/salinity/density relationships and the characterization of real seawater |
author_facet |
Pawlowicz, R. Wright, D. G. Millero, F. J. |
author_sort |
Pawlowicz, R. |
title |
The effects of biogeochemical processes on oceanic conductivity/salinity/density relationships and the characterization of real seawater |
title_short |
The effects of biogeochemical processes on oceanic conductivity/salinity/density relationships and the characterization of real seawater |
title_full |
The effects of biogeochemical processes on oceanic conductivity/salinity/density relationships and the characterization of real seawater |
title_fullStr |
The effects of biogeochemical processes on oceanic conductivity/salinity/density relationships and the characterization of real seawater |
title_full_unstemmed |
The effects of biogeochemical processes on oceanic conductivity/salinity/density relationships and the characterization of real seawater |
title_sort |
effects of biogeochemical processes on oceanic conductivity/salinity/density relationships and the characterization of real seawater |
publishDate |
2018 |
url |
https://doi.org/10.5194/os-7-363-2011 https://os.copernicus.org/articles/7/363/2011/ |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
eISSN: 1812-0792 |
op_relation |
doi:10.5194/os-7-363-2011 https://os.copernicus.org/articles/7/363/2011/ |
op_doi |
https://doi.org/10.5194/os-7-363-2011 |
container_title |
Ocean Science |
container_volume |
7 |
container_issue |
3 |
container_start_page |
363 |
op_container_end_page |
387 |
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1766133186455142400 |