Atmospheric Levels of CO2 Continue to Rise

Tom Boden
Environmental Sciences Division
Oak Ridge National Laboratory
Oak Ridge, Tennessee

Data provided to the Carbon Dioxide Information Analysis Center (CDIAC) and records compiled by the CDIAC show atmospheric levels of carbon dioxide (CO2) and releases from fossil-fuel consumption globally continue to rise (see figure below).

Records representative of background tropospheric CO2 conditions furnished by the Global Monitoring Division of the National Oceanic and Atmospheric Administration (GMD/NOAA) and Scripps Institution of Oceanography (SIO) show annual levels of CO2 have risen above 375 parts per million (ppm). The rise, pattern, and trends are seen at sites worldwide and from continuous monitoring sites, as well as sites that employ less frequent flask sampling techniques. The longest continuous record of direct CO2 measurements is from Mauna Loa, Hawaii dating back to the late 1950s when annual CO2 levels were approximately 315 ppm.

Global records of fossil-fuel CO2 emissions and releases resulting from cement production show that more than 7 billion metric tons of carbon are now released annually to the atmosphere. Since 1751 over 300 billion metric tons of carbon have been released to the atmosphere from the consumption of fossil fuels and cement production. Half of these emissions have occurred since the mid 1970s. The latest CDIAC 2003 global fossil-fuel CO2 emission estimate, 7303 million metric tons of carbon, represents an all-time high and a 4.5% increase from 2002.



Carbon Dioxide Information Analysis Center  ORNL Environmental Sciences Division  Oak Ridge National Laboratory  United States Department of Energy