TY - JOUR T1 - In situ calcium carbonate dissolution in the Pacific Ocean JF - Global Biogeochemical Cycles Y1 - 2002 A1 - Feely, R. A. A1 - Sabine, C. L. A1 - Lee, K. A1 - Millero, F. J. A1 - Lamb, M. F. A1 - Greeley, D. A1 - Bullister, J. L. A1 - Key, R. M. A1 - Peng, T. H. A1 - Kozyr, A. A1 - Ono, T. A1 - Wong, C. S. KW - anthropogenic co(2) KW - anthropogenic co2 KW - aragonite saturation KW - atmospheric carbon KW - caco(3) dissolution KW - calcite saturation KW - carbonate lysocline KW - chemical lysocline KW - coccolithophore emiliania-huxleyi KW - indian-ocean KW - north pacific KW - organic-matter KW - Pacific Ocean KW - panama basin KW - particulate matter AB - 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 mumol kg(-1) yr(-1) 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 m mol kg(-1) yr(-1)). 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 40degreesS, is 157 Pg C. This amounts to an average dissolution rate of approximately 0.31 Pg C yr(-1). 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. VL - 16 SN - 0886-6236 IS - 4 N1 - 649rqTimes Cited:86 Cited References Count:60 JO - Global Biogeochem Cy ER - TY - JOUR T1 - Inorganic carbon in the Indian Ocean: Distribution and dissolution processes JF - Global Biogeochemical Cycles Y1 - 2002 A1 - Sabine, C. L. A1 - Key, R. M. A1 - Feely, R. A. A1 - Greeley, D. KW - alkalinity KW - anthropogenic co2 KW - arabian sea KW - calcium carbonate KW - Carbon cycle KW - dioxide system KW - dissociation KW - indian ocean KW - pressure KW - saturation state KW - SEAWATER KW - Temperature KW - thermodynamics KW - total alkalinity KW - total co2 KW - water AB - This study uses nearly 25,000 carbon measurements from the WOCE/JGOFS global CO2 survey to examine the distribution of dissolved inorganic carbon (DIC) and total alkalinity (TA) in the Indian Ocean. Shallow and intermediate distributions of inorganic carbon do not strictly follow temperature and salinity because of differing surface gradients and vertical biological processes that work to modify the circulation derived features. Anthropogenic CO2 has increased the shallow DIC by as much as 3%, decreasing the vertical DIC gradient. Deep ocean DIC and TA increase toward the north because of the decomposition and dissolution of organic and inorganic particles. Calcite saturation depths range from 2900-3900 m with the deepest saturation depth in the central Indian Ocean. Variations of aragonite saturation depth (200-1400 m) are similar to calcite, but the deepest saturations are in the southwestern Indian Ocean. The shallowest aragonite saturation depths are found in the Bay of Bengal. In the northern Arabian Sea and Bay of Bengal, the current aragonite saturations are 100 and 200 m shallower, respectively, than in preindustrial times. Estimates of carbonate dissolution rates on isopycnal surfaces range from 0.017 to 0.083 mumol kg(-1) yr(-1) in deep waters. Upper water column dissolution rates range from 0 to 0.73 mumol kg(-1) yr(-1), with a local maximum occurring in intermediate waters just below the aragonite saturation horizon. Dissolution is also generally higher north of the Chemical Front at 10-20degreesS. There is some evidence for significant sedimentary sources in the northern Indian Ocean. VL - 16 SN - 0886-6236 IS - 4 N1 - 643rkTimes Cited:50 Cited References Count:72 JO - Global Biogeochem Cy ER -