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The Princeton Atmospheric CO2 Monitoring Project


The Princeton Atmospheric CO2 Monitoring Project makes continuous measurements of the concentration of CO2 on the Princeton campus.  The Project is sponsored by the Grand Challenges program of the Princeton Environmental Institute (PEI).  We track changes in the CO2 concentration of local air that illustrate fundamental processes of the carbon cycle and reflect all the processes influencing the concentration of CO2 in the global atmosphere.  The measurements provide records that are used in University classes to illustrate the basic phenomena affecting the level of CO2 in air and the influence of human activity on the atmospheric CO2 burden.

The Princeton Atmospheric CO2 Monitoring Project uses a Picarro Cavity Ringdown Spectrometer ( to make continuous measurements of the CO2 concentration as well as the carbon isotope composition.  The instrument is used for research projects involving studies of CO2 in seawater and studies of the rate of respiration by plants.  It is also used in course laboratories.  When it is not being used for these purposes, it measures the CO2 concentration of air from an intake on the roof of Guyot Hall; these data can be plotted below and downloaded from this site.

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