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Air Quality: Carbon Dioxide

Volume 710: debated on Monday 11 May 2009

Question

Asked by

To ask Her Majesty's Government what is the present level of carbon dioxide in the atmosphere in parts per million. [HL3173]

The concentration of carbon dioxide in the atmosphere varies seasonally and regionally. Data collected by the Earth System Research Laboratory at the US National Oceanic and Atmospheric Administration indicate that the globally averaged concentration in 2008 was 385 parts per million by volume. (It is important to note that this value may change slightly, depending on recalibration of the reference gas mixtures used, and other quality control procedures).