JGOFS

Gaillard, J.-F. and Treguer, P. (1997). Antares I France JGOFS in the Indian Sector of the Southern Ocean Benthic and water column processes. Deep-Sea Res. 1144, 951-1176. 

Murray, J. W., LeBorgne, R. and Dandonneau, Y. (eds) (1997). A JGOFS Process Study in the Equatorial Pacific. Deep-Sea Res. II44,1759-2317. 

Smith, S. (ed.) (1998). U.S. JGOFS Arabian Sea Process Study. Deep-Sea Res. II45. 

Southern Ocean JGOFS The UK "Sterna" Study in the Bellingshausen Sea. Deep-Sea Res. II 42, 907-1335. 

Results of the past decade JGOFS and other studies... 

A major opportunity to test the use of " Th as a proxy for POC flux arose with the Joint Global Ocean Flux Study (JGOFS). JGOFS had as a central goal a better understanding of the ocean carbon cycle, including the flux of POC leaving the euphotic zone. Process studies were carried out in the Atlantic Ocean, Pacific Ocean, Arabian Sea and Southern Ocean. " Th profiles were obtained as a part of each process study. 

Sampling artifacts. The use of in situ pumps to collect water samples for " Th analysis permits simultaneous collection (and separation) of different particle fractions as well as dissolved Th. As pumping systems have been modified to permit determination of POC on the pump filters, it became possible to compare POC determined from the pump samples with conventional POC determinations made on small volume samples (0.5 - 2 L) taken from hydrocasts. The JGOFS data from multiple studies show large discrepancies between these two sample collection methods, with pump POC values 3 to 100 times lower than bottle POC values. Possible artifacts with each approach have been identified. For example Moran et al. (1999) have suggested that DOC is adsorbed onto... 

Buesseler KO, Bacon MP, Cochran JK, Livingston HD (1992b) Carbon and nitrogen export during the JGOFS North Atlantic Bloom Experiment estimated from " Th U disequilibria. Deep-Sea Res I 39 1115-1137... 

Cochran JK, Buesseler KO, Bacon MP, Livingston HD (1993). Thorium isotopes as indicators of particle dynamics in the upper ocean Results from the JGOFS North Atlantic Bloom Experiment. Deep-Sea... 

Lochte K, Anderson RF, Francois R, Jahnke RA, Shimmield G, Vetrov A (in press) Benthic processes and the bnrial of carbon. In Ocean Biogeochemistiy A JGOFS Synthesis. Fasham M, Zeitzschel B, Platt T (eds)... 

An early attempt to resolve the discrepancy between the high values of Sugimura and Suzuki (1988) and more traditional analyses failed to reach a definitive conclusion (Williams, 1992). The start of the Joint Global Ocean Flux Study (JGOFS) field program with the North Atlantic Bloom Experiment in 1989 put additional pressure on the various groups to resolve this issue quickly. The National Science Foundation (NSF) and the National Oceanic and Atmospheric Administration (NOAA) funded a workshop held in Seattle in July 1991 to resolve the issue. 

The urgent need for nutrient standards was demonstrated during the recently completed World Ocean Circulation Experiment (WOCE) and Joint Global Ocean Flux Study (JGOFS) measurements which were made by different laboratories. The internal consistency of the nutrient data was evaluated by comparing measurements made in deep water (depth over 3500 m) at nearby stations on different cruises. If one assumes that nutrient concentrations in deep water at the same location should not... 

NOTE Activities are reported as disintegrations per minute/gram carbon (dpm/gC). The natural-level abundances are based on the activity of oxalic acid (NIST SRM 4990) and use the 5730 year half-life of 14c (Karlen et al., 1964). The productivity work abundance is based on published JGOFS protocols for measuring primary productivity (Karl et al., 1996). ... 

Sharp, J.H., R. Benner, L. Bennett, C.A. Carlson, S.E. Fitzwater, E.T. Peltzer, and L.M. Tupas. 1995. Analyses of dissolved organic carbon in seawater The JGOFS EQPAC methods... 

JGOFS Joint Global Ocean Flux Study... 

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