Monthly atmospheric CO2 record from Ocean Station C, U.S.A.

Graphics Digital Data

Pieter P. Tans and Thomas J. Conway

NOAA Climate Monitoring and Diagnostics Laboratory, Boulder, Colorado 80305, U.S.A.

Period of Record


Ocean Station C, U.S.A.
Open ocean
54°00; N, 35°00' W
6 m above MSL


The ocean sampling site on Ocean Station "Charlie", in the North Atlantic, was operated in cooperation with NOAA's National Weather Service from November 1968 to May 1973. The annual atmospheric CO2 mixing ratio at Ocean Station "C" rose from 324.03 parts per million (ppm) in 1969 to 327.54 ppm in 1972.

Atmospheric CO2 mixing ratios from this North Atlantic site show a seasonal pattern: the annual minimum typically occurs in August; the annual maximum, in April-May.

CITE AS: Tans, Pieter P. and T.J. Conway, 2005. Monthly Atmospheric CO2 Mixing Ratios from the NOAA CMDL Carbon Cycle Cooperative Global Air Sampling Network, 1968-2002. 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.

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