This work presents an estimate of anthropogenic CO2 in the Pacific Ocean based on measurements from the WOCE/JGOFS/OACES global CO2 survey. These estimates used a modified version of the ΔC* technique. Modifications include a revised preformed alkalinity term, a correction for denitrification, and an evaluation of the disequilibrium terms using an optimum multiparameter analysis. The total anthropogenic CO2 inventory over an area from 120°E to 70°W and 70°S to 65°N (excluding the South China Sea, the Yellow Sea, the Japan/East Sea, and the Sea of Okhotsk) was 44.5 ± 5 Pg C in 1994. Approximately 28 Pg C was located in the Southern Hemisphere and 16.5 Pg C was located north of the equator. The deepest penetration of anthropogenic CO2 is found at about 50°S. The shallowest penetration is found just north of the equator. Very shallow anthropogenic CO2 penetration is also generally observed in the high‐latitude Southern Ocean. One exception to this is found in the far southwestern Pacific where there is evidence of anthropogenic CO2 in the northward moving bottom waters. In the North Pacific a strong zonal gradient is observed in the anthropogenic CO2 penetration depth with the deepest penetration in the western Pacific. The Pacific has the largest total inventory in all of the southern latitudes despite the fact that it generally has the lowest average inventory when normalized to a unit area. The lack of deep and bottom water formation in the North Pacific means that the North Pacific inventories are smaller than the North Atlantic.

[1] Over the past several years researchers have been working to synthesize the WOCE/ JGOFS global CO 2 survey data to better understand carbon cycling processes in the oceans. The Pacific Ocean data set has over 35,000 sample locations with at least two carbon parameters, oxygen, nutrients, CFC tracers, and hydrographic parameters. In this paper we estimate the in situ CaCO 3 dissolution rates in the Pacific Ocean water column. Calcium carbonate dissolution rates ranging from 0.01-1.1 mmol kg À1 yr À1 are observed in intermediate and deepwater beginning near the aragonite saturation horizon. In the North Pacific Intermediate Water between 400 and 800 m, CaCO 3 dissolution rates are more than 7 times faster than observed in middle and deep water depths (average = 0.051 mmol kg À1 yr À1). The total amount of CaCO 3 that is dissolved within the Pacific is determined by integrating excess alkalinity throughout the water column. The total inventory of CaCO 3 added by particle dissolution in the Pacific Ocean, north of 40°S, is 157 Pg C. This amounts to an average dissolution rate of approximately 0.31 Pg C yr À1 . This estimate is approximately 74% of the export production of CaCO 3 estimated for the Pacific Ocean. These estimates should be considered to be upper limits for in situ carbonate dissolution in the Pacific Ocean, since a portion of the alkalinity increase results from inputs from sediments.

This paper presents a comprehensive analysis of the basin‐wide inventory of anthropogenic CO2 in the Atlantic Ocean based on high‐quality inorganic carbon, alkalinity, chlorofluorocarbon, and nutrient data collected during the World Ocean Circulation Experiment (WOCE) Hydrographic Program, the Joint Global Ocean Flux Study (JGOFS), and the Ocean‐Atmosphere Carbon Exchange Study (OACES) surveys of the Atlantic Ocean between 1990 and 1998. Anthropogenic CO2 was separated from the large pool of dissolved inorganic carbon using an extended version of the ΔC* method originally developed by Gruber et al. [1996]. The extension of the method includes the use of an optimum multiparameter analysis to determine the relative contributions from various source water types to the sample on an isopycnal surface. Total inventories of anthropogenic CO2 in the Atlantic Ocean are highest in the subtropical regions at 20°–40°, whereas anthropogenic CO2 penetrates the deepest in high‐latitude regions (>40°N). The deeper penetration at high northern latitudes is largely due to the formation of deep water that feeds the Deep Western Boundary Current, which transports anthropogenic CO2 into the interior. In contrast, waters south of 50°S in the Southern Ocean contain little anthropogenic CO2. Analysis of the data collected during the 1990–1998 period yielded a total anthropogenic CO2 inventory of 28.4 ± 4.7 Pg C in the North Atlantic (equator‐70°N) and of 18.5 ± 3.9 Pg C in the South Atlantic (equator‐70°S). These estimated basin‐wide inventories of anthropogenic CO2 are in good agreement with previous estimates obtained by Gruber [1998], after accounting for the difference in observational periods. Our calculation of the anthropogenic CO2 inventory in the Atlantic Ocean, in conjunction with the inventories calculated previously for the Indian Ocean [Sabine et al., 1999] and for the Pacific Ocean [Sabine et al., 2002], yields a global anthropogenic CO2 inventory of 112 ± 17 Pg C that has accumulated in the world oceans during the industrial era. This global oceanic uptake accounts for approximately 29% of the total CO2 emissions from the burning of fossil fuels, land‐use changes, and cement production during the past 250 years.

[1] Recent independent lines of evidence suggest that the dissolution of calcium carbonate (CaCO 3 ) particles is substantial in the upper ocean above the calcite 100% saturation horizon. This shallow-water dissolution of carbonate particles is in contrast with the current paradigm of the conservative nature of pelagic CaCO 3 at shallow water depths. Here we use more than 20,000 sets of carbon measurements in conjunction with CFC and 14 C data from the WOCE/JGOFS/OACES global CO 2 survey to estimate in situ dissolution rates of CaCO 3 in the Atlantic Ocean. A dissolution rate is estimated from changes in alkalinity as a parcel of water ages along an isopycnal surface. The in situ CaCO 3 dissolution increases rapidly at the aragonite 100% saturation horizon. Estimated dissolution rates north of 40 o N are generally higher than the rates to the south, which is partly attributable to the production of exported CaCO 3 being higher in the North Atlantic than in the South Atlantic. As more CaCO 3 particles move down the water column, more particles are available for in situ dissolution. The total water column CaCO 3 dissolution rate in the Atlantic Ocean is determined on an annual basis by integrating estimated dissolution rates throughout the entire water column and correcting for alkalinity input of approximately 5.6 Â 10 12 mol C yr À1 from CaCO 3 -rich sediments. The resulting water column dissolution rate of CaCO 3 for the Atlantic Ocean is approximately 11.1 Â 10 12 mol C yr À1 . This corresponds to about 31% of a recent estimate (35.8 Â 10 12 mol C yr À1 ) of net CaCO 3 production by Lee [2001] for the same area. Our calculation using a large amount of high-quality water column alkalinity data provides the first basin-scale estimate of the CaCO 3 budget for the Atlantic Ocean.