World Ocean Circulation Experiment

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... 

Data from GEOSECS, TTO, BATS, and HOTS and other major oceanographic research projects, such as the WOCE (World Ocean Circulation Experiment) are available online. The GEOSECS, TTO, and WOCE datasets are part of the Java Ocean Atlas, which provides a graphic exploration environment for generating vertical profiles, cross-sections, and property-property plots. Many of the data presented in this text were obtained from this source. 

Chlorofluorocarbon (CFC) compounds (Freons ) are important tracers of ocean circulation. Since CFC-11 and CFC-12 were released at different rates, their concentrations as well as their ratios can be used to determine when a water mass left contact with the sea surface over the 50 years since Freons were released into the atmosphere and taken up by the ocean. CFC-113 and carbon tetrachloride are being investigated as additional tracers. Picomole levels of CFCs dissolved in seawater are determined using a gas chromatograph equipped with an electron capture detector. The World Ocean Circulation Experiment (WOCE) Hydrographic Program calls for measurements with a precision and accuracy of 1% and a detection limit of... 

Based on data from the World Ocean Circulation Experiment, average profile. Estimated uncertainty about 20%. Average profile from 4 process studies of the Joint Global Ocean Flux Study data, see also Fig. 1.3. Estimated uncertainty about 20%. 

Figure 1.6 Plots of CO-variances of (A) phosphate, and (B) dissolved inorganic carhon (D/C) with nitrate. DIG has heen normalized to a constant salinity of35 in order to remove the effect of freshwater fluxes. B ased on data from all depth and from selected cruises ofthe World Ocean Circulation Experiment, i.e., A16,18NI9S, P16.The lines indicate the expectedhiologically induced trends.

Ganachaud, A., and Wunsch, C. (2002). Oceanic nutrient and oxygen transports and bounds on export production during the World Ocean Circulation Experiment. Global Biogeochem. Cycles 16, 5/1-5/14. 

Figure 4 Vertical profiles of total dissolved inorganic carbon (TIC) in the ocean. Curve A corresponds to a theoretical profile that would have been obtained prior to the Industrial Revolution with an atmospheric CO2 concentration of 280 ixmol mol The curve is derived from the solubility coefficients for CO2 in seawater, using a typical thermal and salinity profile from the central Pacific Ocean, and assumes that when surface water cools and sinks to become deep water it has equilibrated with atmospheric CO2. Curve B corresponds to the same calculated solubility profile of TIC, but in the year 1995, with an atmospheric CO2 concentration of 360 xmol moPk The difference between these two curves is the integrated oceanic uptake of CO2 from anthropogenic emissions since the beginning of the Industrial Revolution, with the assumption that biological processes have been in steady state (and hence have not materially affected the net influx of CO2). Curve C is a representative profile of measured TIC from the central Pacific Ocean. The difference between curve C and B is the contribution of biological processes to the uptake of CO2 in the steady state (i.e. the contribution of the biological pump to the TIC pool.) (courtesy of Doug Wallace and the World Ocean Circulation Experiment).

WOCE, 2002. World Ocean Circulation Experiment, Global Data, Version 3.0, WOCE International Project Office, WOCE Report, Southampton, UK published by U.S. National Oceanographic Data Center, Silver Spring, 180/02, DVD-ROM. 

Figure 2 Vertical profiles of oceanographic data. (A) North Pacific salinity and potential temperature, (B) North Pacific CFC-11 and CFC-12, (C) North Pacific oxygen, (D) North Atlantic salinity and potential temperature, (E) North Atlantic CFC-11 and CFC-12, (F) North Atlantic oxygen. North Pacific World Ocean Circulation Experiment cruise P17C station 20, 33°N, 135°W, June 1991 North Atlantic Subtropical Atlantic Climate Studies cruise station 7, 26.5°N, 76°W, June 1990. (North Atlantic data from Johns etal. (1997) Journal of Physical Oceanography 27 2187-2208 Pacific data from Fine etal. (2001) Journal of Geophysical Research.)...

United Nations Educational, Scientific and Cultural Organization World Ocean Circulation Experiment... 

The following sections describe methods of handling, calibration and data processing that are necessary to obtain high quality salinity results from CTD data. They summarize procedures that are described in more detail by UNESCO (1988), the World Ocean Circulation Experiment (1994), and Millard and Yang (1993). 

World Ocean Circulation Experiment (1994), WOCE Report No. 68/91, Revision 1, November 1994, Woods Hole, MA, USA. 

For oxygen determinations within the framework of WOCE (World Ocean Circulation Experiment) an algorithm to convert the CTD oxygen sensor measurements into oxygen profiles based on the documented sensor physics and in situ oxygen data of discrete samples is described in the WOCE Opierations Manual (WHP, 1994). The achievable accuracy and precision is < 1 % and 0.1 %, respjectively. 

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