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Processes affecting the oceanic distribution of carbon dioxide

The stoichiometric model of organic decomposition in seawater
(Redfield, Ketchum, and Richards, 1963) was used to describe the
oceanic distribution of total carbon dioxide. It was assumed that the
concentration of total carbon dioxide was the sum of three terms:
(1) the initial concentration of carbon dioxide, (2) the increase in
carbon dioxide due to the oxidation of organic matter, and (3) the
increase in carbon dioxide due to the solution of calcium carbonate.
The initial concentration of carbon dioxide was calculated by assuming
that surface seawater is in equilibrium with atmospheric carbon
dioxide. This assumption allowed the temperature dependence of the
initial concentration to be estimated. The vertical and horizontal
distribution of total carbon dioxide in the Pacific, Indian, and South
Atlantic Oceans was shown to conform to this model. In particular,
values of the oxidative ratio (ΔC/ΔO) calculated from field data agreed
with the theoretical value of Redfield et al. (1963).
The model for the distribution of total carbon dioxide was applied
to the vertical distribution of carbon-13 at the North Pacific (1969)
GEOSECS intercalibration station (Kroopnick, Deuser, and Craig,
1970). Values of δC¹³ calculated from the stoichiometric model
agreed to within ± 0.3‰ with the measured values at this station.
Near-bottom chemical measurements were made on three
cruises: YALOC-69 to the Eastern Tropical Pacific, Y6908F off the
Oregon Coast, and TT-46 to the Caribbean Sea and North Atlantic.
The emphasis during these cruises was on chemical gradients in
deep water, and 39 stations were occupied at depths greater than
2000 m. Salinity, oxygen, pH, alkalinity, silicate, phosphate,
nitrate, and nitrite were measured at heights from 0.5 to 300 m
above the bottom. No measurable salinity, oxygen, silicate, phosphate,
nitrate, or nitrite gradients were observed. A statistically
significant near-bottom increase in pH and alkalinity was found.
However, the increase was small and could have resulted from
undetected analytical and/or sampling errors. / Graduation date: 1972

Identiferoai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/29001
Date03 May 1972
CreatorsCulberson, Charles Henry
ContributorsPytkowicz, Richardo M.
Source SetsOregon State University
Languageen_US
Detected LanguageEnglish
TypeThesis/Dissertation

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