Geochemistry of particulate and dissolved inorganic carbon in the central North Pacific

Thesis/Dissertation · Wed Jan 01 04:00:00 EST 1992

OSTI ID:6874253

Sabine, C L

An understanding of the global biogeochemical cycle of carbon is fundamental to an evaluation of global climate change. One important aspect of the global carbon cycle is the relationship between carbonate particles and the dissolved carbon chemistry of the world oceans. The carbon-carbonate system of the open ocean is still not completely understood today. This investigation incorporated both sediment trap data and measurements of the concentration and distribution of marine carbon species in the water column in an attempt to evaluate some of the fundamental questions of the marine carbon system. These include the relationship between particulate and dissolved inorganic carbon and the importance of bank-derived carbonate particles on the carbon chemistry of the open ocean. The marine carbon-carbonate system, monitored for 15 months at the Hawaii Ocean Time-series station, ALOHA, was predominantly controlled by the decomposition of organic matter in the upper 700 m of the water column and by the dissolution of aragonite between 700 and 2200 m. Calcite particle dissolution does not appear to be significant at depths shallower than 3200 to 3500 m. Although mixed layer pCO[sub 2] calculations suggest that the central North Pacific waters are a very small sink for anthropogenic CO[sub 2], this CO[sub 2] has penetrated to a depth of 700 m at Station ALOHA and may already be dissolving aragonite particles at this depth. Magnesian calcite particles comprise as much as 15% of the carbonate flux at 400 m at Station ALOHA and may also be reacting with anthropogenic CO[sub 2] in the water column. Dissolution of these magnesian calcites may contribute to the alkalinity maximum observed in the North Pacific. Carbonate fluxes near banks of the Hawaiian Archipelago were up to two orders of magnitude greater than open ocean fluxes with significant contributions of bank-derived material.

• Research Organization: Hawaii Univ., Honolulu, HI (United States)
• OSTI ID: 6874253
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540310* -- Environment
Aquatic-- Basic Studies-- (1990-)
CARBON
CARBON COMPOUNDS
CARBON CYCLE
CARBON DIOXIDE
CARBON OXIDES
CHALCOGENIDES
CLIMATIC CHANGE
ELEMENTS
NONMETALS
OXIDES
OXYGEN COMPOUNDS
PACIFIC OCEAN
SEAS
SEDIMENTATION
SOLUBILITY
SURFACE WATERS