* in parts per million ppm, or ppmv (volume)
+ residency time in
the atmosphere, how long a molecule, on average stays active in solution,
or in the air.
** current measure: April 2012 at Mauna Loa.
375 parts per million or ppm circa 2004
In 1969, CO2
measurement was 318 ppm. In 1990 it was 360 ppm.
Today it is increasing
at more than the 50 year average rate of 1.5 ppm /annum. In 2000-2007, green
house gas content of the atmosphere was increasing at 2 ppm in bad
years and 1.7 ppm in good years.
*** 7-24-2000 discovered by atmospheric chemists
Carbon dioxide measured @ 383.1 ppm in 2007.
Carbon dioxide measured @ 394.45 ppm March, 2012.
U.S. Department of Commerce, NOAA: Trends in Atmospheric Carbon Dioxide web site,
• Monthly recent carbon dioxide at Mauna Loa
• full range from 1958-present graphic
and Global Change, Brasseur, Orlando, & Tyndall, eds. (New York: Oxford University Press, 1999). p. 9.
Mark Bush, Ecology of a Changing Planet. Upper Saddle River, N. J.: Prentice-Hall, 2000. pp. 361-368.