This document presents the procedures and methods used to obtain carbon dioxide (CO2), hydrographic, and chemical data during the R/V Meteor Expedition 11/5 in the South Atlantic Ocean, including the Drake Passage (Section A-12); the Northern Weddell Sea; and the Eastern South Atlantic Ocean (Section A-21). This cruise was conducted as part of the World Ocean Circulation Experiment (WOCE).
The cruise started from Ushuaia, Argentina, on January 23, 1990, and ended at Capetown, South Africa on March 8, 1990. Samples were collected at 78 stations that covered the Drake Passage (56-63oS); the Northern Weddell Sea (45-35oW); a section along the 58oW parallel (25oW-prime meridian); and two segmented S-N sections between the Northern Weddell Sea and Capetown, South Africa. Measurements taken at WOCE sections A-12 and A-21 included pressure, temperature, salinity measured by the Conductivity, Temperature and Depth sensor (CTD); bottle salinity; oxygen; phosphate; nitrate; nitrite; silicate; total carbon concentration (TCO2); and partial pressure of CO2 (pCO2) measured at 20oC. In addition, potential density at 0 decibar (dbar) and potential temperature were calculated from the measured variables.
The TCO2 concentration in seawater samples was measured using a coulometer with an estimated precision of approximately 1 µmol/kg. The coulometer was calibrated frequently at sea by using a high- precision gas pipette and CO2 gas (99.998%). The pCO2 value in seawater samples was measured at 20oC by means of a constant volume (500 ml seawater) equilibrator and a gas chromatograph. CO2 in equilibrated gas was first converted to methane, by using a ruthenium catalyst, and then measured by a flame-ionization detector. The precision of pCO2 measurements has been estimated to be approximately 0.1%.
The CO2 investigation during the R/V Meteor Cruise 11/5 was supported by a grant from the U.S. Department of Energy (No. DE-FGO2-90ER60943).
The data set is available, free of charge, as a Numeric Data Package (NDP) from CDIAC. The NDP consists of seven data files and this printed documentation, which describes the contents and format of all data files as well as the procedures and methods used to obtain these data during the R/V Meteor Cruise 11/5.
- Chipman, D. W., T. Takahashi, D. Breger, and S. C. Sutherland. 1994. Carbon Dioxide, Hydrographic, and Chemical Data Obtained During the R/V Meteor Cruise 11/5 in the South Atlantic and Northern Weddell Sea Areas (WOCE sections A-12 and A-21). ORNL/CDIAC-55, NDP-045. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, Oak Ridge, Tennessee. doi: 10.3334/CDIAC/otg.ndp045