NOTICE (August 2016): CDIAC as currently configured and hosted by ORNL will cease operations on September 30, 2017. Data will continue to be available through this portal until that time. Data transition plans are being developed with DOE to ensure preservation and availability beyond 2017.

image image image image

Atmospheric Carbon Dioxide Record from Station "C"

graphics Graphics   data Data


A.M. Brounshtein,* A.A. Shashkov, N.N. Paramonova, V.I. Privalov, Y.A. Starodubtsev
Main Geophysical Observatory,
Karbyshev Str. 7, 194018
St. Petersburg, Russia

A major part of the Russian atmospheric CO2 monitoring program in 1993-94 was financed through Project 96-1 of the Environmental Research Support Scheme of the Central European University in Budapest, established by George Soros. We are grateful to George Soros and to the Advisory Board of the Central European University Environmental Department for their kind attention and support.

Period of Record



Air is collected generally four times per month in pairs of 1.5-L stainless steel electropolished flasks with one greaseless stainless steel stopcock. Sampling is performed by opening the stopcock of the flasks, which have been evacuated at the central laboratory at the Main Geophysical Observatory (MGO). The air is not dried during sample collection. Attempts are made to obtain samples when the wind speed is >5 m/s and the wind direction corresponds to the predetermined "clean air" sector.

After the air samples are collected, the flasks are mailed to the central laboratory at the MGO once per month for CO2 determinations, which are made through the use of a URAS-2T nondispersive infrared gas analyzer. Storage times between sample collection and analysis range from 2 to 6 months. Air samples are dried cryogenically before analysis.

The URAS-2T nondispersive infrared gas analyzer is calibrated by using CO2-in-synthetic air reference gases. All gases were initially calibrated at the Scripps Institution of Oceanography (SIO) against the primary standards maintained by the World Meteorological Organization (WMO) and against NOAA/GMCC standards in 1981. In 1988 and 1989, MGO reference gases were compared with a NOAA/GMCC set of three travelling CO2-in-air gas standards. During 1990-93, 13 series of calibrations were performed against a set of 5 CO2-in-air-standards provided by the Atmospheric Environment Service (AES) of Canada. On the basis of these calibration experiments, all MGO data were recalculated to a new scale that is closely related to the WMO X87 scale through the AES standards. A 2-year field comparison program with AES, involving a regular exchange of air samples from Alert and Teriberka, showed that data from both programs are comparable within 0.2 parts per million (ppm).

Concentration values for both flasks in a pair are accepted if the difference between the values is <1 ppmv. More details about the sampling methods and selection criteria are provided in Brounshtein et al. (1985, 1988a, 1988b, 1988c) and in Shashkov and Paramonova (in press).

Map showing location of Station 'C', North Atlantic Ocean

Station "C"
North Atlantic Ocean
Open ocean
52°45' N, 35°30' W
5 m above MSL


An open ocean site in the North Atlantic, east of Greenland, was established in 1968 and was operated in cooperation with NOAA's National Weather Service through 1973. The Main Geophysical Observatory collected flask samples at the site from January 1983 through October 1990. The yearly mean atmospheric CO concentration at Station "C" rose from 348.15 parts per million by volume (ppmv) in 1985 to 354.33 ppmv in 1989.


  • Brounshtein, A.M., N.N. Paramonova, A.D. Frolov, and A.A. Shashkov. 1976. Optical method for determination of CO2 total abundance in a vertical column of the atmosphere. Trudy GGO 369:5-25.
  • Brounshtein, A.M., E.V. Faber, and A.A. Shashkov. 1985. Study of measuring specifications of UGAN-CO2 instrument. Trudy GGO 496:55-65.
  • Brounshtein, A.M., K.V. Kazakova, E.V. Faber, and A.A. Shashkov. 1988a. Measurements of the CO2 concentration vertical distribution above the continental regions. Annals of the MGO 519:34-42.
  • Brounshtein, A.M., E..V. Faber, and A.A. Shashkov. 1988b. Measurements of the CO2 concentration above Leningrad. Annals of the MGO 519:43-45.
  • Brounshtein, A.M., K.V. Kazakova, V.I. Medinez, and E.V. Faber. 1988c. Measurements of the CO2 concentrations at Ocean Station "C" (North Atlantic). Annals of the MGO 519:27-43.
  • Brounshtein, A.M., E.V. Faber, and A.A. Shashkov. 1991. Atmospheric CO2 concentrations derived from flask samples collected at U.S.S.R.-Operated Sampling Sites. NDP-033. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tennessee.
  • Shashkov, A.A., and N.N. Paramonova (in press). Atmospheric CO2 monitoring in Russia. In G.I. Pearman and J.T. Peterson (eds.), Report of the Seventh WMO Meeting of Experts on Carbon Dioxide Concentration and Isotopic Measurement Techniques (September 7-10, 1993, Rome, Italy). World Meteorological Organization, Geneva.

CITE AS: Brounshtein, A.M., A.A. Shashkov, N.N. Paramonova, V.I. Privalov, and Y.A. Starodubtsev. 1994. Atmospheric CO2 records from sites in the Main Geophysical Observatory air sampling network. In Trends: A Compendium of Data on Global Change. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tenn., U.S.A.